
==== Front
Sci Rep
Sci Rep
Scientific Reports
2045-2322
Nature Publishing Group UK London

71981
10.1038/s41598-024-71981-4
Article
Simplified synthesis and identification of novel nanostructures consisting of cobalt borate and cobalt oxide for crystal violet dye removal from aquatic environments
Al-Wasidi Asma S. 1
El-Feky Hesham H. hesham.feky2010@yahoo.com

2
Shah Reem K. 3
Saad Fawaz A. 3
Abdelrahman Ehab A. EAAAhmed@imamu.edu.sa

24
1 https://ror.org/05b0cyh02 grid.449346.8 0000 0004 0501 7602 Department of Chemistry, College of Science, Princess Nourah Bint Abdulrahman University, 11671 Riyadh, Saudi Arabia
2 https://ror.org/03tn5ee41 grid.411660.4 0000 0004 0621 2741 Chemistry Department, Faculty of Science, Benha University, Benha, 13518 Egypt
3 https://ror.org/01xjqrm90 grid.412832.e 0000 0000 9137 6644 Department of Chemistry, Faculty of Science, Umm Al-Qura University, 21955 Makkah, Saudi Arabia
4 https://ror.org/05gxjyb39 grid.440750.2 0000 0001 2243 1790 Present Address: Department of Chemistry, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), 11623 Riyadh, Saudi Arabia
16 9 2024
16 9 2024
2024
14 216312 8 2024
2 9 2024
© The Author(s) 2024
2024
https://creativecommons.org/licenses/by-nc-nd/4.0/ Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.
Crystal violet dye poses significant health risks to humans, including carcinogenic and mutagenic effects, as well as environmental hazards due to its persistence and toxicity in aquatic ecosystems. This study focuses on the efficient removal of crystal violet dye from aqueous media using novel Co3O4/Co3(BO3)2 nanostructures synthesized via the Pechini sol–gel approach. The nanostructures, which were abbreviated to EN600 and EN800, were fabricated at calcination temperatures of 600 and 800 °C, respectively. X-ray diffraction (XRD) analysis revealed that the synthesized samples have a cubic Co3O4 phase and an orthorhombic Co3(BO3)2 phase, with mean crystal sizes of 43.82 nm and 52.93 nm for EN600 and EN800 samples, respectively. The Brunauer–Emmett–Teller (BET) surface areas of EN600 and EN800 samples were 65.80 and 43.76 m2/g, respectively, indicating a significant surface area available for adsorption. Optimal removal of crystal violet dye was achieved at a temperature of 298 K, a contact time of 70 min, and a pH of 10. The maximum adsorption capacities were found to be 284.09 mg/g for EN600 and 256.41 mg/g for EN800, which are notably higher compared to many conventional adsorbents. The adsorption process followed the pseudo-second-order kinetic model and fitted well with the Langmuir isotherm. The adsorption was exothermic, spontaneous, and physical in nature. Moreover, the adsorbents exhibited excellent reusability, retaining high efficiency after multiple regeneration cycles using 6 mol/L hydrochloric acid. These findings highlight the potential of these Co3O4/Co3(BO3)2 nanostructures as effective and sustainable materials for water purification applications.

Keywords

Co3(BO3)2/Co3O4 nanostructures
Identification
Decontamination
Crystal violet dye
Subject terms

Pollution remediation
Nanoparticle synthesis
issue-copyright-statement© Springer Nature Limited 2024
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pmcIntroduction

Aquatic contamination with organic chemical dyes is a considerable environmental subject stemming from various industrial activities1–4. The primary sources include the textile, leather, paper, and plastics industries, where dyes are extensively used to color products5,6. These industries often discharge untreated or inadequately treated effluents containing high concentrations of dyes into water bodies. Additionally, the use of dyes in pharmaceuticals, cosmetics, and food processing further contributes to water pollution7,8. Improper disposal of dye-containing wastes and accidental spills during transportation and storage are also critical factors leading to the release of dyes into the aquatic environment. Organic dyes in water pose major environmental and human health risks. Environmentally, dyes can inhibit light penetration in water bodies, affecting photosynthetic activity and disrupting aquatic ecosystems. This can lead to reduced oxygen levels and the death of aquatic flora and fauna. Dyes can also form toxic by-products through chemical reactions, further aggravating their environmental impact9–11. For humans, subjected to polluted water can induce several health difficulties. Some dyes are carcinogenic, mutagenic, and teratogenic, posing long-term health risks such as cancer and genetic mutations. Skin contact with dye-contaminated water can cause dermatitis and other skin disorders. Ingestion of contaminated water can induce gastrointestinal disturbances, liver and kidney damage, and other systemic effects12–14. Crystal violet dye, also known as gentian violet, is particularly hazardous to human health. It is extensively utilized in the textile and microbiological industries and has found purposes as a medicinal antiseptic. However, crystal violet is a potent mutagen and has been classified as a potential carcinogen. Chronic exposure can lead to severe health problems, including cancer, organ toxicity, and reproductive issues. Ingestion or prolonged skin contact can result in skin irritation, respiratory problems, and damage to vital organs such as the liver and kidneys15,16. Different approaches, such as adsorption17,18, electrochemical 19, photocatalytic decomposition20, as well as biological21, have been designed to eliminate organic dyes from wastewater. Adsorption involves the accumulation of dye molecules on the surface of solid adsorbents. It is widely used owing to its simplicity, efficiency, and cost-effectiveness22. Common adsorbents include activated carbon, clay minerals, and metal oxides23–25. Electrochemical methods use electric current to degrade dye molecules. Techniques like electrocoagulation, electrooxidation, and electroflotation are employed to remove dyes from water. These methods are effective but can be energy-intensive and costly26–28. Photocatalytic degradation utilizes light-activated catalysts to break down dye molecules into less harmful substances. Titanium dioxide is a commonly used photocatalyst. This method is environmentally friendly but can be limited by the availability of suitable light sources29. The synthesis and application of novel materials offer significant advantages for environmental remediation, particularly in adsorption and photocatalysis processes30–37. Enhanced adsorption efficiency for heavy metals and organic pollutants, including Pb(II) ions, coupled with effective photocatalytic degradation of dyes such as eriochrome black T and trinitrophenol, has been demonstrated38,39. Biological methods involve the use of microorganisms to degrade dyes. Bacteria, fungi, and algae can metabolize dye molecules, converting them into non-toxic substances. While this approach is eco-friendly, it may require longer treatment times and specific environmental conditions40–42. The adsorption method offers several advantages over other dye removal techniques, such as efficiency, simplicity, cost-effectiveness, versatility, and environmental impact. Adsorption can effectively remove dyes at low concentrations and is capable of achieving high removal efficiencies. The process is straightforward and does not require complex equipment or highly skilled operators. Adsorbents are often inexpensive and can be regenerated and reused, reducing overall treatment costs43. Nano-metal oxides have gained prominence in adsorption due to their unique properties. Their high surface area, tunable pore sizes, and active surface sites enhance their sorption capacity and potency. Nano-metal oxides, for example, ZnO/MgO and CaFe2O4 exhibit excellent adsorption performance for a variety of organic dyes. Their ability to interact with dye molecules through various pathways, encompassing electrostatic attraction, van der Waals forces, and hydrogen bonding, makes them highly effective adsorbents44,45. Co3O4-based nanocomposites, such as Co/Co3O4, ZnCo2O4/Co3O4, and reduced graphene oxide/Co3O4, have demonstrated excellent adsorption and photocatalytic properties for various dyes in wastewater treatment applications46–48. Its high surface area, coupled with active surface sites, allows for efficient interactions with pollutants, making it a versatile adsorbent for environmental remediation49. No direct studies currently focus on the use of Co3(BO3)2 for pollutant separation. However, research on similar borate compounds, such as magnesium borate (Mg3(BO3)2), has shown promising results in adsorption applications. For instance, magnesium borate has demonstrated high efficiency in removing dyes from wastewater due to its structural properties and high surface area50. The Pechini sol–gel method is a versatile and efficient technique for synthesizing metal nanooxides. It involves the formation of a polymeric network through the reaction of metal salts with a chelating agent (typically citric acid) and a crosslinker (such as ethylene glycol). This method offers several advantages, such as control over composition and structure, uniform particle size, scalability, and versatility51. In this research, novel Co3O4/Co3(BO3)2 nanostructures were synthesized using the Pechini sol–gel method with citric acid as a chelating agent and ethylene glycol as a crosslinker. The combination of cobalt oxide (Co3O4) and cobalt borate (Co3(BO3)2) phases in a single material is unique, leveraging the synergistic effects of these components. This novel material composition is not extensively explored in previous research. This method’s versatility and cost-effectiveness in producing high-performance adsorbents is a notable improvement over other approaches used in similar studies. The resulting nanostructures exhibit high surface area, uniform morphology, and enhanced adsorption properties towards crystal violet dye, making them suitable for water treatment applications. Also, the excellent reusability and minimal efficiency loss after multiple regeneration cycles position these nanostructures as more practical and cost-effective compared to many existing adsorbents, enhancing their significance for real-world applications.

Experimental

Materials

Ethylene glycol (C2H6O2), Boric acid (H3BO3), cobalt nitrate hexahydrate (Co(NO3)2·6H2O), citric acid (C₆H8O7), hydrochloric acid (HCl), sodium hydroxide (NaOH), crystal violet dye (C25H30ClN3), as well as potassium chloride (KCl) were bought from the Sigma-Aldrich Chemical Company. Each material was employed in its original form without any additional purification steps.

Synthesis of Co3O4/Co3(BO3)2 nanostructures

Co3O4/Co3(BO3)2 nanostructures were synthesized using the Pechini sol–gel method50. In this regard, 7.56 g of Co(NO3)2·6H2O was solubilized in 70 mL of distilled water. Similarly, 1.51 g of H3BO3 was solubilized in another 70 mL of distilled water. Besides, the two aqueous solutions were then combined and stirred continuously for 5 min. Following this, citric acid solution, which was prepared by solubilizing 6.30 g of citric acid in 70 mL of distilled water, was incorporated into the mixture under vigorous stirring for another 15 min. Next, 6 mL of ethylene glycol was added, and the blend was heated to 120 °C until total evaporation of the water was achieved. The resulting powder underwent calcination at 600 and 800 °C to produce Co3O4/Co3(BO3)2 nanostructures, designated as EN600 and EN800, respectively. Figure 1 illustrates the synthesis process of Co3O4/Co3(BO3)2 nanostructures. It is worth mentioning that the addition of 6.30 g of citric acid is based on the stoichiometric ratio required for chelation and complex formation in the Pechini sol–gel method. Citric acid serves as a chelating agent that binds to cobalt and borate ions, forming a stable metal-citrate complex. This chelation is crucial for ensuring homogeneity and controlled particle growth during the synthesis process.Fig. 1 Synthesis of Co3O4/Co3(BO3)2 nanostructures.

Instrumentation

X-ray diffraction (XRD) patterns of the EN600 and EN800 samples were obtained using an X-ray diffractometer (D8 Discover, Bruker, USA). The Fourier transform infrared (FTIR) spectra of the EN600 and EN800 products were acquired utilizing an FTIR spectrometer (Nicolet IS10, Thermo Fisher Scientific, USA). The surface features of the EN600 and EN800 samples were investigated utilizing a field emission scanning electron microscope (FEG Quanta 250, FE-SEM, Thermo Fisher Scientific, USA). The particle morphology of the EN600 and EN800 samples was investigated utilizing a high-resolution transmission electron microscope (HRTEM, JEM-2100Plus, JEOL Ltd., Japan). The surface properties of the EN600 and EN800 products were acquired utilizing a nitrogen gas analyzer (NOVA2000 series, Quantachrome, USA). Energy dispersive X-ray (EDX) spectra of the EN600 and EN800 samples were obtained using a detector (X-Max 20, Oxford, England) attached to FE-SEM.

Removal of crystal violet dye from aquatic environments

The effectiveness of crystal violet dye removal was assessed in a dark place utilizing EN600 or EN800 adsorbents under various conditions, as outlined in Table 1. The experiments employed 100 mL solutions of crystal violet dye at a concentration of 150 mg/L, treated with 50 mg of the adsorbent. Adjusted variables included pH values between 2 and 10, contact times varying between 10 and 100 min, and temperatures varying between 298 and 328 K, as detailed in Table 1. Furthermore, the effects of crystal violet dye concentrations, between 50 and 250 mg/L, were evaluated while maintaining a constant solution volume as well as adsorbent dosage. The experimental procedure included stirring the crystal violet solutions for predetermined durations, separating the synthesized adsorbent through centrifugation, and subsequently calculating the remaining concentration of crystal violet dye at 590 nm utilizing an ultraviolet–visible (UV–Vis) spectrophotometer (Cintra 3030, GBC, Australia) to evaluate the adsorption performance.Table 1 Experimental conditions for removing crystal violet dye from aquatic environments utilizing the EN600 and EN800 adsorbents.

Effect	Volume of studied dye solution (mL)	Concentration of studied dye (mg/L)	Amount of adsorbent (mg)	Temperature (K)	Time (min)	Solution pH	
pH	100	150	50	298	360	2–10	
Time	100	150	50	298	10–100	10	
Temperature	100	150	50	298–328	70	10	
Concentration of dye	100	50–250	50	298	70	10	

Equations (1) and (2) were utilized to determine the adsorption capacity (O, mg/g) and removal efficiency (R %) of the synthesized adsorbents52,53.1 O=Co-Ce×VWz

2 R%=Co-CeCo×100

Co indicates the preliminary concentration of crystal violet dye, expressed in mg/L. Ce indicates the residual concentration of crystal violet dye at equilibrium, also in mg/L. V refers to the volume of the crystal violet dye solution, measured in liters (L). W denotes the weight of the adsorbent used, measured in grams (g).

Elution was performed using hydrochloric acid (HCl) at 2, 4, and 6 M concentrations, with 50 mL of each concentration being used, to regenerate adsorbents saturated with crystal violet dye.

Equation (3) was employed to determine the desorption potential (D %) of crystal violet dye from the utilized adsorbent54.3 D%=100CdVd(Co-Ce)V

Vd indicates the desorptive solvent volume, measured in liters (L). Cd denotes the crystal violet dye concentration in the desorption solvent, expressed in mg/L.

Upon completion of regeneration, the durability and effectiveness of the utilized adsorbents were assessed over five successive cycles. In each cycle, 100 mL of a dye solution having a concentration of 150 mg/L was treated with an amount of 0.05 g of the adsorbent. Besides, the experimental settings, including a temperature of around 298 K, a contact time of 70 min, as well as a pH of 10, were consistently preserved throughout each cycle. After that, the adsorbent was separated by centrifugation, and then the remaining concentration of crystal violet dye was determined at 590 nm utilizing an ultraviolet–visible (UV–Vis) spectrophotometer.

Estimation of point of zero charge (pHPZC) for the EN600 and EN800 products

To assess the pHPZC for the EN600 and EN800 products, a batch procedure was implemented55. Initial pH measurements (pHi) of 60 mL potassium chloride (KCl) solutions were set using 0.1 M NaOH or HCl and registered before the addition of 0.12 g of the synthesized adsorbent. Moreover, after 10 h of continuous mixing, the final pH measurements (pHf) were registered. The differences between the initial and final pH points (∆pH) were plotted with respect to the initial pH points. Furthermore, the point where the ∆pH against pHi curve intersects the horizontal axis represents the pHPZC.

Results and discussion

Production and identification of Co3O4/Co3(BO3)2 nanostructures

The formation of Co3O4/Co3(BO3)2 nanostructures via the Pechini sol–gel method involves a series of reactions that each play an essential role in the construction of the final product. Initially, cobalt nitrate hexahydrate undergoes dissociation to produce cobalt ions, as shown in Eq. (4).4 CoNO32·6H2O→Co2++2NO3-+6H2O

Following this, boric acid reacts with water to produce borate ions, which are vital for the next stages of synthesis, as shown in Eq. (5).5 H3BO3+H2O→BOH4-+H+

The cobalt ions then interact with the borate ions and citric acid to form a [CoB(Citrate)] complex, as demonstrated in Eq. (6).6 Co2++BOH4-+C6H8O7→CoBCitratecomplex+4H2O

Ethylene glycol is subsequently introduced into the mixture, serving as an interlinking agent. Also, it undergoes a reaction with the carboxyl functional groups present in the citrate of the metal coordination complex, resulting in the establishment of ester bonds. This reaction leads to polymerization, producing a stable and viscous gel that effectively encapsulates the metal ions homogeneously within the framework. The resultant thick gel is then subjected to drying. This process eliminates water and initiates the solidification of the coordination complex. Finally, the polymeric network is subjected to heat, resulting in the formation of cobalt oxide and cobalt borate, alongside the evolution of carbon dioxide and water, as demonstrated in Eq. (7).7 Polymericnetwork+heat→Co3BO32+Co3O4+CO2+H2O

XRD analysis was utilized to investigate the structural properties of the EN600 and EN800 products, as demonstrated in Fig. 2A,B, respectively. Both samples contain two distinct crystalline phases: Co3O4 (82.91%), which crystallizes in a cubic system, and Co3(BO3)2 (17.10%), which crystallizes in an orthorhombic system. These phases are confirmed by their respective JCPDS files, with Co3O4 being linked to JCPDS No. 00-009-0418 and Co3(BO3)2 to JCPDS No. 00-025-0102. The characteristic peaks at 2Ɵo (hkl) values of 33.32° (121), 40.03° (211), 42.33° (102), 52.33° (202), 54.63° (132), 60.50° (330), 61.41° (142), and 68.58° (251), indicate the orthorhombic structure of Co3(BO3)2. The characteristic peaks at 2Ɵo (hkl) values of 19.01° (111), 31.29° (220), 36.82° (311), 38.56° (222), 44.79° (400), 55.73° (422), 59.40° (511), and 65.28° (440), indicate the cubic structure of Co3O4. The average crystal size of the EN600 sample is 43.82 nm, while the EN800 sample exhibits a larger average crystal size of 52.93 nm. This increase in average crystal size can be attributed to the higher temperature, which promotes the formation of larger crystals. These values are comparable to those reported for other cobalt-based nanocomposites, such as ZnCo2O4/Co3O4 (40–60 nm) synthesized by Heidari-Asil et al., where higher temperatures similarly resulted in increased crystal sizes47. Additionally, the crystal structure comparison aligns with findings from other borate compounds like magnesium borate (Mg3(BO3)2), which exhibit similar crystalline behavior50.Fig. 2 XRD patterns of the EN600 (A) and EN800 (B) products.

Table 2 tabulates the surface characteristics of both samples. Also, the N2 adsorption/desorption isotherms for both samples, as depicted in Fig. 3, exhibit a type IV isotherm with a noticeable H3 hysteresis loop, characteristic of mesoporous materials50. The isotherm curves reveal that the EN600 sample adsorbs more N2 at higher relative pressures compared to the EN800, aligning with its larger pore volume and surface area, as shown in Table 2. The BET surface area and total pore volume are higher for the EN600 sample compared to the EN800 sample. This suggests that the EN600 sample possesses a more porous structure, potentially facilitating enhanced N2 adsorption capabilities. The average pore sizes of the EN600 and EN800 samples are relatively similar, with values of 8.12 and 8.38 nm, respectively. Despite the minor difference in average pore size, this similarity implies that the overall porosity characteristics of the samples are comparable in terms of the size of the pores, although the total number and volume of these pores differ. The BET surface area for EN600 (65.80 m2/g) is significantly higher than that of EN800 (43.76 m2/g), which corresponds to their enhanced adsorption capabilities. These values are notably larger than those reported for other nanocomposites, such as Mn0.5Zn0.5Fe2O4/Fe2O3 (43.18 m2/g), copper oxide/cobalt manganese oxide/manganese oxide (33.37 m2/g), and MgO/Cu3MgO4 (42.20 m2/g)56–58.Table 2 BET surface textures of the EN600 and EN800 products.

Surface textures	EN600	EN800	
Total pore volume (cc/g)	0.2672	0.1834	
BET surface area (m2/g)	65.80	43.76	
Average pore size (nm)	8.12	8.38	
Isotherm type	Type IV	Type IV	
Hysteresis loop type	Type H3	Type H3	

Fig. 3 N2 adsorption/desorption isotherms of the EN600 and EN800 products.

FE-SEM analysis was conducted on the EN600 and EN800 products, as depicted in Fig. 4A,B, respectively. In the images, variations in the surface morphology and grain sizes of the two samples are clearly observed. The average grain size for the EN600 sample is 0.23 µm, where a denser and more uniform distribution of smaller grains is evident. Conversely, a larger average grain size of 0.34 µm is noted in the EN800 sample, along with a less uniform distribution of grains, indicating a coarser structure. These morphological properties are almost similar to those observed in several nanocomposites, such as ZnO/MgO composite (average grain size ~ 0.37 µm), Mn0.5Zn0.5Fe2O4/Fe2O3 (average grain size ~ 0.47 µm), and copper oxide/cobalt manganese oxide/manganese oxide (average grain size ~ 0.42 µm) which are known for their high adsorption efficiency due to similar structural attributes44,57,59. The smaller grain size and denser distribution in EN600 likely lead to more available active sites for adsorption, which directly enhances its efficiency in dye removal compared to EN800. This structural difference aligns with the observed higher BET surface area and adsorption capacity of EN600.Fig. 4 FE-SEM images of the EN600 (A) and EN800 (B) products.

HR-TEM analysis was conducted on the EN600 and EN800 samples, as outlined in Fig. 5A,B, respectively. The EN600 sample displayed an average particle diameter of 102.84 nm, where the particles appear somewhat agglomerated. Conversely, the EN800 sample has a larger average diameter of 148.89 nm, which is indicative of significant coalescence among particles. The difference in particle sizes between the EN600 (102.84 nm) and EN800 (148.89 nm) samples, can be attributed to the increased calcination temperature for EN800, which leads to greater particle growth and agglomeration. The higher calcination temperature of 800 °C enhances atomic diffusion and crystal growth, resulting in larger particle sizes due to the sintering effect. This behavior is consistent with findings reported in the literature for similar nanostructures, such as ZrO2/MgMn2O4/Mg(Mg0.333Mn1.333)O4, barium titanate, and ZrO2/CdMn2O4/CdO60–62. The larger particle size in EN800 reduces its surface area, negatively impacting its adsorption efficiency compared to EN600. It is noted that the observed differences in particle sizes between the HR-TEM and XRD analyses are attributed to the tendency of the samples to coalesce. This coalescence leads to larger apparent sizes in the HR-TEM images compared to the crystallite sizes determined by XRD, which typically measures the size of coherent scattering regions within the crystals.Fig. 5 HR-TEM images of the EN600 (A) and EN800 (B) products.

Figure 6A,B represents the FTIR absorption spectra of the EN600 and EN800 products, respectively. Besides, the stretching vibration modes associated with Co(III)-O in an octahedral coordination and Co(II)-O in a tetrahedral coordination within Co3O4 were recorded at 581 and 676 cm−1 for EN600 and 553 and 638 cm−1 for EN800, respectively63. Moreover, the B-O-B bending vibrations were noted at 883 cm−1 for EN600 and 869 cm−1 for EN800. The B-O-B symmetric stretching vibration modes showed at 1181 cm−1 for EN600 and 1163 cm−1 for EN800. The B-O-B asymmetric stretching vibrations appeared at 1285 cm−1 for EN600 and 1257 cm−1 for EN80064,65. Bending vibration modes from adsorbed water were identified at 1648 cm−1 for EN600 and 1630 cm−1 for EN800. Additionally, the stretching vibration modes of adsorbed water were recorded at 3439 cm−1 for EN600 and 3433 cm−1 for EN80066. The FTIR spectra for EN600 and EN800 products are discussed, showing vibration modes associated with Co(III)-O and Co(II)-O bonds and the specific B-O-B bending and stretching vibrations that confirm the presence of Co3(BO3)2. The peak positions (e.g., 581 and 676 cm−1 for EN600 and 553 and 638 cm−1 for EN800) are detailed, explaining how these correspond to the nanostructures identified through XRD.Fig. 6 FTIR Spectra of the EN600 (A) and EN800 (B) products.

The elemental composition of the EN600 and EN800 nanostructures was determined through energy dispersive X-ray (EDX) analysis, as illustrated in Fig. 7A,B, respectively. The EDX spectra, as shown in Table 3, confirm the presence of cobalt (Co), oxygen (O), and boron (B) elements, aligning with the expected composition of the Co3(BO3)2/Co3O4 composite.Fig. 7 EDX patterns of the EN600 (A) and EN800 (B) products by EDX.

Table 3 Elemental composition of the EN600 and EN800 products.

Samples	Weight percentage	
Co	O	B	
EN600	68.10	30.20	1.70	
EN800	70.24	28.23	1.53	

Removal of crystal violet dye from aquatic environments

Influence of dye solution pH

In the analysis presented in Fig. 8A, the influence of solution pH on the elimination percentage of crystal violet dye applying the EN600 and EN800 adsorbents was systematically examined. The disposal percentage of the crystal violet dye was observed to increase with rising pH values for both samples. The highest removal percentage was observed at pH 10, with EN600 achieving 93.17% and EN800 achieving 82.91%.Fig. 8 (A) Correlation between primarily pH values and the elimination percentage of crystal violet dye by EN600 and EN800 adsorbents. (B) Measurement of pHPZC for the EN600 as well as EN800 products.

The relationship between pH and adsorption efficacy is closely linked to the point of zero charge (pHPZC) of the adsorbents, which was detected to be 6.75 for EN600 and 7.28 for EN800, as shown in Fig. 8B. The point of zero charge is critical, as it indicates the pH at which the surface charge of the adsorbent is neutral. Below the pHPZC, the surface of the adsorbents is positively charged, enhancing electrostatic repulsion with the positively charged crystal violet dye molecules, thus explaining the decreased dye removal efficiency as shown in Fig. 967. Above the pHPZC, the surface of the adsorbents becomes negatively charged, enhancing electrostatic attraction with the positively charged crystal violet dye molecules and thus explaining the increased crystal violet removal efficiency as indicated in Fig. 968.Fig. 9 The mechanism of adsorption of crystal violet dye using Co3O4/Co3(BO3)2 nanostructures.

Influence of contact time

Figure 10 exhibits the systematic study of crystal violet dye removal using EN600 and EN800 adsorbents at different times. An increasing trend in the percentage of crystal violet dye removal was observed from 10 to 70 min for both samples. The highest removal percentage was observed at 70 min, with EN600 achieving 92.45% and EN800 achieving 82.38%. Beyond 70 min, both adsorbents reached a plateau in crystal violet dye removal efficiency owing to the saturation of active sites69.Fig. 10 Correlation between contact time and the percentage of crystal violet dye removed by EN600 and EN800 adsorbents.

The findings were analyzed with the application of pseudo-second-order in addition to the pseudo-first-order kinetic models, as depicted in Eqs. (8) and (9), respectively52,53.8 tOt=1F2Oe2+1Oet

9 logOe-Ot=logOe-F12.303t

Measured in mg/g, Ot and Oe indicate the amount of crystal violet dye separated at contact time t in addition to at equilibrium, respectively.

Furthermore, F1 and F2 are the rate constants for the pseudo-first-order in addition to the pseudo-second-order models, respectively, quantified in 1/min and g/mg min. Figure 11A,B display the utilization of both pseudo-second-order and pseudo-first-order models in the adsorption of crystal violet dye utilizing EN600 and EN800 adsorbents, respectively. Table 4 lists the kinetic parameters associated with the discarding of crystal violet dye using these adsorbents. The evaluation of the kinetic findings reveals that the pseudo-second-order provides a more precise fit than the pseudo-first-order, as corroborated by the greater R2 values of 0.9999 for EN600 in addition to 0.9997 for EN800 in the pseudo-second-order, in contrast to 0.9612 as well as 0.9767 in the pseudo-first-order for the same materials, respectively. Additionally, the close match between the Oe values and OEXP in the pseudo-second-order reveals that the discarding of crystal violet dye onto the EN600 and EN800 products predominantly adheres to this model. Moreover, the rate constants for EN600 (0.000355 g/mg min) and EN800 (0.000276 g/mg min) align with those reported for metal oxide adsorbents like ZnO/MgO and ZrO2/CdMn2O4/CdO composites44,61.Fig. 11 The pseudo-second-order (A) in addition to the pseudo-first-order (B) kinetic models for disposing of crystal violet dye by EN600 and EN800 products.

Table 4 Kinetic constants for crystal violet dye removal by EN600 and EN800 adsorbents.

Adsorbent	OExp (mg/g)	Pseudo-first-order	Pseudo-second-order	
F1 (1/min)	R2	Oe (mg/g)	F2 (g/mg.min)	R2	Oe (mg/g)	
EN600	277.36	0.0238	0.9612	159.80	0.000355	0.9999	275.48	
EN800	247.14	0.0237	0.9767	166.41	0.000276	0.9997	252.53	

Effect of temperature

The effectiveness of the EN600 and EN800 adsorbents in removing crystal violet dye at different temperatures was assessed, as depicted in Fig. 12A. Both adsorbents demonstrated a consistent decrease in the percentage of crystal violet dye removal as the solution temperature elevated from 298 K up to 328 K.Fig. 12 (A) Correlation between temperature and the percentage of crystal violet dye removed by EN600 and EN800 adsorbents. (B) The graph of ln Fd against 1/T.

Equations (10), (11), and (12) were employed to calculate the Gibbs free energy (ΔG°), entropy change (ΔS°), as well as enthalpy change (ΔH°) for the discarding of crystal violet dye utilizing the EN600 and EN800 products5810 lnFd=ΔS∘R-ΔH∘RT

11 ΔG∘=ΔH∘-TΔS∘

12 Fd=OeCe

Fd, T, and R symbolize the distribution coefficient, temperature, and gas constant, respectively, measured in units of L/g, K, and kJ/molK. Figure 12B illustrates the graph of ln Fd vs. 1/T for the discarding of studied crystal violet dye by the EN600 and EN800 products. Table 5 details the previous thermodynamic constants for the adsorption operation using these adsorbents. The positive alteration in entropy (ΔS > 0) suggests that the disposal of crystal violet dye onto the EN600 or EN800 adsorbents is feasible, marked by a growth in irregularity at the liquid–solid boundary. An alteration in enthalpy (ΔH) fewer than 40 kJ/mol indicates that the elimination mechanism is principally physical. The negative enthalpy change (ΔH < 0) demonstrates the exothermic nature of the adsorption process. A negative Gibbs free energy change (ΔG < 0) indicates that the disposal of crystal violet dye is a spontaneous process. These findings regarding thermodynamic parameters are consistent with those reported in similar composites, such as ZnO/MgO and ZrO2/CdMn2O4/CdO44,61.Table 5 Thermodynamic parameters for crystal violet dye removal using the EN600 and EN800 products.

Adsorbent	ΔS° (kJ/molK)	ΔH° (kJ/mol)	ΔG° (kJ/mol)	
298	308	318	328	
EN600	0.0767	− 30.74	− 53.58	− 54.35	− 55.12	− 55.88	
EN800	0.0452	− 19.10	− 32.58	− 33.03	− 33.48	− 33.93	

Effect of concentration

The removal efficiency of crystal violet dye from aqueous solutions using EN600 and EN800 adsorbents decreases as the initial concentration of the crystal violet dye elevates, as revealed in Fig. 13. This trend may be assigned to the fullness of the provided adsorption positions on the adsorbents. At lower crystal violet dye concentrations, there are more accessible active centers relative to the number of crystal violet dye particles, leading to greater removal efficiency. Nevertheless, as the crystal violet dye concentration increases, the available adsorption positions become saturated, and the removal efficiency per unit mass of adsorbent decreases. This is because the adsorbents reach their maximum capacity, while the excess dye molecules remain in the solution.Fig. 13 Correlation between preliminary concentration of dye and the percentage of crystal violet dye removed by EN600 and EN800 adsorbents.

The experimental results for the disposal of crystal violet dye on EN600 and EN800 adsorbents were evaluated using both the Langmuir (Eq. 13) and Freundlich (Eq. 14) isotherms52,53.13 CeOe=1F3Omax+CeOmax

14 lnOe=lnF4+1nlnCe

where, Ce operates as the equilibrium concentration of the crystal violet dye (mg/L), Oe operates as the amount of crystal violet dye adsorbed per unit mass of adsorbent (mg/g), Omax operates as the maximum adsorption capacity (mg/g), F3 is the Langmuir constant (L/mg), F4 is the Freundlich constant (mg/g) (L/mg)1/n), and n is the heterogeneity factor. Equation (15) represents the calculation of Omax from the Freundlich equilibrium isotherm70.15 Omax=F4Co1/n

The uptake behavior of crystal violet dye on EN600 and EN800 adsorbents was investigated through the Langmuir and Freundlich isotherms, as illustrated in Fig. 14A,B and detailed in Table 6. The adsorption process does not follow the Freundlich isotherm, as indicated by the lower correlation coefficients (R2) of 0.6076 for EN600 and 0.6741 for EN800. The Langmuir isotherm, which assumes monolayer adsorption on a surface with a finite number of identical sites, fits the experimental results exceptionally well, as indicated by the high correlation coefficients (R2) of 0.9998 for EN600 and 0.9994 for EN800. The maximum adsorption capacity (Omax) obtained from the Langmuir model is 284.09 mg/g for EN600 and 256.41 mg/g for EN800. This suggests that EN600 has a slightly higher capacity for crystal violet dye removal compared to EN800, possibly due to differences in surface properties or pore structure. Moreover, these findings regarding equilibrium constants are consistent with those reported in similar composites, such as ZnO/MgO and ZrO2/CdMn2O4/CdO44,61.Fig. 14 Langmuir (A) in addition to Freundlich (B) graphs for the adsorption of crystal violet dye by EN600 and EN800 products.

Table 6 Langmuir and Freundlich isotherm parameters for EN600 and EN800 products.

Adsorbent	Langmuir	Freundlich	
Omax (mg/g)	R2	F3 (L/mg)	F4 (mg/g)(L/mg)1/n	Omax (mg/g)	1/n	R2	
EN600	284.09	0.9998	0.8980	132.94	344.72	0.1902	0.6076	
EN800	256.41	0.9994	0.3971	100.30	299.03	0.2180	0.6741	

This study compared the elimination capacity of multiple adsorbents for crystal violet dye, as outlined in Table 771–79. EN600 exhibited the highest capacity at 284.09 mg/g, followed by EN800 at 256.41 mg/g, both significantly outperforming other adsorbents. The exceptional performance of recently established EN600 and EN800 products demonstrates their viability for enhanced crystal violet dye removal from effluents. These observations emphasize developments in adsorption procedures and the crucial significance of matter engineering in environmental decontamination. The crystal size plays a crucial role in determining the surface area and the availability of active sites for adsorption. The smaller nanoparticle size in EN600 (43.82 nm) corresponds to a higher BET surface area (65.80 m2/g) compared to EN800 (52.93 nm, 43.76 m2/g). This difference is a critical factor influencing the adsorption capacity, with EN600 showing a higher maximum adsorption capacity of 284.09 mg/g for crystal violet dye, compared to 256.41 mg/g for EN800. This finding is consistent with literature, where smaller nanoparticle sizes typically lead to higher adsorption efficiencies due to the increased surface area and better dispersion of nanoparticles within the solution.Table 7 Evaluation of maximum elimination capacities for different adsorbents concerning crystal violet dye.

Adsorbent	Omax (mg/g)	References	
Polypyrrole-decorated bentonite magnetic composite	78.74	71	
Poly(acrylamide)-Kaolin	25.00	72	
Natural zeolite	177.75	73	
Magnetic g-poly(methacrylic acid)-κ-carrageenan	28.24	74	
Fe3O4/sodium dodecyl sulphate composite	166.70	75	
Silica aerogel	137.17	76	
Silver/graphene oxide composite	48.78	77	
Activated carbon/Fe3O4 composite	35.30	78	
Calcium oxide modified fly ash	32.12	79	
EN600	284.09	This study	
EN800	256.41	This study	

Assessment of regeneration and reusability

This research evaluated the impact of different HCl concentrations on the discarding of crystal violet dye from EN600 and EN800 adsorbents, as shown in Fig. 15. The findings revealed that increasing HCl concentrations enhanced crystal violet dye removal efficiency for both adsorbent types. At a 6 M concentration, desorption efficiencies were 99.86% for EN600 and 99.93% for EN800. These results indicate a strong correlation between desorption efficiency and the acidity level of the eluent. Higher HCl concentrations likely improve desorption percentages by breaking the bonds between crystal violet dye particles and adsorbent surfaces. Besides, the nearly whole crystal violet dye removal at this concentration emphasizes the feasibility of reactivating and reusing the adsorbents. The research highlights the necessity of optimizing the eluent concentration to maximize crystal violet dye recovery and promote the sustainable use of adsorbents. It also demonstrates that both EN600 and EN800 adsorbents are highly effective for repeated use with strong desorption performance.Fig. 15 Efficiency of crystal violet dye desorption from EN600 and EN800 adsorbents at varying HCl concentrations.

The repeated application of EN600 and EN800 products for the extraction of crystal violet dye was comprehensively tested across multiple cycles, as illustrated in Fig. 16. The crystal violet dye removal efficiency demonstrated stable behavior throughout the five cycles, implying that the adsorbents maintained their performance despite repeated use. This stable performance across multiple cycles underscores the economic feasibility and prolonged effectiveness of these products in water purification processes.Fig. 16 Reusability of EN600 and EN800 products across multiple cycles for crystal violet dye adsorption.

The structural stability of the EN600 and EN800 adsorbents after multiple adsorption–desorption cycles was thoroughly analyzed using XRD (Figures omitted for brevity). The XRD patterns of the reused EN600 and EN800 samples indicate that the crystalline phases of Co3O4 and Co3(BO3)2 remain stable after repeated cycles. The characteristic peaks for both phases are still present, with only very slight broadening observed, which is attributed to minor changes in crystallite size due to potential surface restructuring during the adsorption–desorption processes80.

Practical application

In a practical demonstration of the utility of Co3O4/Co3(BO3)2 nanostructures, experiments were conducted to assess the adsorption performance of the EN600 and EN800 samples in a student chemistry laboratory wastewater (containing crystal violet dye). For these experiments, 0.05 g of each adsorbent type was introduced into 100 mL of wastewater sample containing crystal violet dye at a concentration of 60 mg/L. The pH of the solution was adjusted to 10, and the system was maintained at room temperature for a contact time of 70 min to simulate typical laboratory conditions. The EN600 sample achieved a crystal violet dye removal efficiency of 97.52%, while the EN800 sample demonstrated an enhanced removal efficiency of 93.29%. This significant efficacy in crystal violet dye removal underscores the potential of Co3O4/Co3(BO3)2 nanostructures, particularly the EN600 type, for application in the wastewater treatment field.

Conclusions

In this work, novel Co3O4/Co3(BO3)2 nanostructures were synthesized via a simple Pechini sol–gel method, representing a unique combination of cobalt oxide and cobalt borate phases tailored for enhanced crystal violet dye adsorption. These nanostructures, which were synthesized at 600 and 800 °C, were abbreviated as EN600 and EN800, respectively. The mean crystal sizes were 43.82 nm for EN600 and 52.93 nm for EN800. The BET surface areas were 65.80 m2/g for EN600 and 43.76 m2/g for EN800, respectively. Optimal removal of crystal violet dye was achieved at a solution temperature of 298 K, an interaction time of 70 min, and a pH of 10. The synthesized EN600 and EN800 nanostructures demonstrate exceptionally high adsorption capacities of 284.09 mg/g and 256.41 mg/g for crystal violet dye, respectively, outperforming many conventional adsorbents. The innovation of this research lies in the development of a dual-phase material that leverages the synergistic effects of cobalt oxide’s high reactivity and cobalt borate’s structural stability. This novel material composition, combined with a scalable and cost-effective synthesis approach, provides a new avenue for sustainable environmental remediation. The adsorption process, which aligns best with the pseudo-second-order model and Langmuir isotherm, was determined to be exothermic, physical, and spontaneous. Besides, the adsorbents were effectively regenerated with 6 M hydrochloric acid and reused several times with minimal efficiency loss, demonstrating their excellent reusability. Future research will focus on scaling up the synthesis of EN600 and EN800 nanostructures for larger-scale environmental remediation applications.

Acknowledgements

The authors are grateful to Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia for funding this work through Researchers Supporting Project number (PNURSP2024R35).

Author contributions

A.S.A.-W.: Funding acquisition, writing—review and editing, H.H.E.-F.: Methodology, R.K.S.: Writing—review and editing, F.A.S.: Writing—review and editing, E.A.A.: Methodology, writing—review and editing, conceptualization.

Funding

This research was funded by Princess Nourah bint Abdulrahman University Researchers Supporting Project number (PNURSP2024R35), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia.

Data availability

All data generated or analyzed during this study are included in this published article.

Competing interests

The authors declare no competing interests.

Institutional review board statement

The authors ensure that the paper hereby submitted is completely original and has not been previously published in any format or language, either partially or in its complete form anywhere else. This study was conducted and approved according to the guidelines of the Declaration of the Ethical Committee of the Faculty of Science, Benha University (No. BuFs-REC-2024-199 Chm).

Publisher's note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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References

1. Anulaya SV Subash A Gholap V Kandasubramanian B Electrospinning of cellulose acetate for methylene blue dye removal Hybrid Adv. 2024 6 100205 10.1016/j.hybadv.2024.100205
Anulaya, S. V., Subash, A., Gholap, V. & Kandasubramanian, B. Electrospinning of cellulose acetate for methylene blue dye removal. Hybrid Adv. 6, 100205 (2024).10.1016/j.hybadv.2024.100205
2. Park D Removal of selected contaminants of dyes and pharmaceuticals using MXene-based nanoadsorbents: A review Sep. Purif. Technol. 2024 341 126864 10.1016/j.seppur.2024.126864
Park, D. et al. Removal of selected contaminants of dyes and pharmaceuticals using MXene-based nanoadsorbents: A review. Sep. Purif. Technol. 341, 126864 (2024).10.1016/j.seppur.2024.126864
3. Gadore V Mishra SR Yadav N Yadav G Ahmaruzzaman M Advances in zeolite-based materials for dye removal: Current trends and future prospects Inorg. Chem. Commun. 2024 166 112606 10.1016/j.inoche.2024.112606
Gadore, V., Mishra, S. R., Yadav, N., Yadav, G. & Ahmaruzzaman, M. Advances in zeolite-based materials for dye removal: Current trends and future prospects. Inorg. Chem. Commun. 166, 112606 (2024).10.1016/j.inoche.2024.112606
4. Xu D Efficient recycling of sewage water in a polyester integrated industry: A case study Desalin. Water Treat. 2024 319 100508 10.1016/j.dwt.2024.100508
Xu, D. et al. Efficient recycling of sewage water in a polyester integrated industry: A case study. Desalin. Water Treat. 319, 100508 (2024).10.1016/j.dwt.2024.100508
5. Kausar A Cellulose-based materials and their adsorptive removal efficiency for dyes: A review Int. J. Biol. Macromol. 2023 224 1337 1355 10.1016/j.ijbiomac.2022.10.220 36309237
Kausar, A. et al. Cellulose-based materials and their adsorptive removal efficiency for dyes: A review. Int. J. Biol. Macromol. 224, 1337–1355 (2023).36309237 10.1016/j.ijbiomac.2022.10.220
6. Athab ZH Comparison activity of pure and chromium-doped nickel oxide nanoparticles for the selective removal of dyes from water Sci. Rep. 2024 14 1 15 10.1038/s41598-024-53490-6 38167627
Athab, Z. H. et al. Comparison activity of pure and chromium-doped nickel oxide nanoparticles for the selective removal of dyes from water. Sci. Rep. 14, 1–15 (2024).38167627 10.1038/s41598-024-53490-6
7. Zhao Z Li L Geleta GS Ma L Wang Z Polyacrylamide-phytic acid-polydopamine conducting porous hydrogel for efficient removal of water-soluble dyes Sci. Rep. 2017 7 1 10 28127051
Zhao, Z., Li, L., Geleta, G. S., Ma, L. & Wang, Z. Polyacrylamide-phytic acid-polydopamine conducting porous hydrogel for efficient removal of water-soluble dyes. Sci. Rep. 7, 1–10 (2017).28127051
8. Liu D Lei W Qin S Chen Y Template-free synthesis of functional 3D BN architecture for removal of dyes from water Sci. Rep. 2014 4 1 5
Liu, D., Lei, W., Qin, S. & Chen, Y. Template-free synthesis of functional 3D BN architecture for removal of dyes from water. Sci. Rep. 4, 1–5 (2014).
9. Ahmadian M Derakhshankhah H Jaymand M Biosorptive removal of organic dyes using natural gums-based materials: A comprehensive review J. Ind. Eng. Chem. 2023 124 102 131 10.1016/j.jiec.2023.05.002
Ahmadian, M., Derakhshankhah, H. & Jaymand, M. Biosorptive removal of organic dyes using natural gums-based materials: A comprehensive review. J. Ind. Eng. Chem. 124, 102–131 (2023).10.1016/j.jiec.2023.05.002
10. Jiao T Facile and scalable preparation of graphene oxide-based magnetic hybrids for fast and highly efficient removal of organic dyes Sci. Rep. 2015 5 1 10 10.1038/srep12451
Jiao, T. et al. Facile and scalable preparation of graphene oxide-based magnetic hybrids for fast and highly efficient removal of organic dyes. Sci. Rep. 5, 1–10 (2015).10.1038/srep12451
11. Zhao X Synthesis of magnetic metal-organic framework (MOF) for efficient removal of organic dyes from water Sci. Rep. 2015 5 1 10
Zhao, X. et al. Synthesis of magnetic metal-organic framework (MOF) for efficient removal of organic dyes from water. Sci. Rep. 5, 1–10 (2015).
12. Aouaini F Statistical physics analysis of the adsorption of reactive red 141dye on residual avocado peel (Persea americana) chemically modified with H2SO4 and HNO3 Inorg. Chem. Commun. 2024 165 112547 10.1016/j.inoche.2024.112547
Aouaini, F. et al. Statistical physics analysis of the adsorption of reactive red 141dye on residual avocado peel (Persea americana) chemically modified with H2SO4 and HNO3. Inorg. Chem. Commun. 165, 112547 (2024).10.1016/j.inoche.2024.112547
13. Kamaraj M β-cyclodextrin polymer composites for the removal of pharmaceutical substances, endocrine disruptor chemicals, and dyes from aqueous solution—A review of recent trends J. Environ. Manag. 2024 351 119830 10.1016/j.jenvman.2023.119830
Kamaraj, M. et al. β-cyclodextrin polymer composites for the removal of pharmaceutical substances, endocrine disruptor chemicals, and dyes from aqueous solution—A review of recent trends. J. Environ. Manag. 351, 119830 (2024).10.1016/j.jenvman.2023.119830
14. Elzahar MMH Bassyouni M Removal of direct dyes from wastewater using chitosan and polyacrylamide blends Sci. Rep. 2023 13 1 16 10.1038/s41598-023-42960-y 36593249
Elzahar, M. M. H. & Bassyouni, M. Removal of direct dyes from wastewater using chitosan and polyacrylamide blends. Sci. Rep. 13, 1–16 (2023).36593249 10.1038/s41598-023-42960-y
15. Al-Ansari SH Gomaa H Abdel-Rahim RD Ali GAM Nagiub AM Recycled gold-reduced graphene oxide nanocomposite for efficient adsorption and photocatalytic degradation of crystal violet Sci. Rep. 2024 14 1 16 10.1038/s41598-024-54580-1 38167627
Al-Ansari, S. H., Gomaa, H., Abdel-Rahim, R. D., Ali, G. A. M. & Nagiub, A. M. Recycled gold-reduced graphene oxide nanocomposite for efficient adsorption and photocatalytic degradation of crystal violet. Sci. Rep. 14, 1–16 (2024).38167627 10.1038/s41598-024-54580-1
16. Gomaa H Abd El-Monaem EM Eltaweil AS Omer AM Efficient removal of noxious methylene blue and crystal violet dyes at neutral conditions by reusable montmorillonite/NiFe2O4@amine-functionalized chitosan composite Sci. Rep. 2022 12 1 16 34992227
Gomaa, H., Abd El-Monaem, E. M., Eltaweil, A. S. & Omer, A. M. Efficient removal of noxious methylene blue and crystal violet dyes at neutral conditions by reusable montmorillonite/NiFe2O4@amine-functionalized chitosan composite. Sci. Rep. 12, 1–16 (2022).34992227
17. Arunkumar G Carbon encapsulated ZnO nanoplates for efficient removal of organic dyes from aqueous medium by adsorption: Role of organic ligand and calcination temperature J. Mol. Liq. 2024 403 124852 10.1016/j.molliq.2024.124852
Arunkumar, G. et al. Carbon encapsulated ZnO nanoplates for efficient removal of organic dyes from aqueous medium by adsorption: Role of organic ligand and calcination temperature. J. Mol. Liq. 403, 124852 (2024).10.1016/j.molliq.2024.124852
18. Şenol ZM Removal of food dyes using biological materials via adsorption: A review Food Chem. 2024 450 139398 10.1016/j.foodchem.2024.139398 38677180
Şenol, Z. M. et al. Removal of food dyes using biological materials via adsorption: A review. Food Chem. 450, 139398 (2024).38677180 10.1016/j.foodchem.2024.139398
19. Zhang Q Cheng Y Liu C Fang C Electrochemical-driven removal of organic dyes by using bimetallic MOFs/waste cellulose acetate derived carbon foam as a freestanding electrode material J. Solid State Chem. 2024 330 124489 10.1016/j.jssc.2023.124489
Zhang, Q., Cheng, Y., Liu, C. & Fang, C. Electrochemical-driven removal of organic dyes by using bimetallic MOFs/waste cellulose acetate derived carbon foam as a freestanding electrode material. J. Solid State Chem. 330, 124489 (2024).10.1016/j.jssc.2023.124489
20. Sukhadeve GK Visible light assisted photocatalytic degradation of Indigo Carmine dye and NO2 removal by Fe doped TiO2 nanoparticles Ceram. Int. 2022 48 29121 29135 10.1016/j.ceramint.2022.05.053
Sukhadeve, G. K. et al. Visible light assisted photocatalytic degradation of Indigo Carmine dye and NO2 removal by Fe doped TiO2 nanoparticles. Ceram. Int. 48, 29121–29135 (2022).10.1016/j.ceramint.2022.05.053
21. Bustos-Terrones YA Removal of BB9 textile dye by biological, physical, chemical, and electrochemical treatments J. Taiwan Inst. Chem. Eng. 2021 121 29 37 10.1016/j.jtice.2021.03.041
Bustos-Terrones, Y. A. et al. Removal of BB9 textile dye by biological, physical, chemical, and electrochemical treatments. J. Taiwan Inst. Chem. Eng. 121, 29–37 (2021).10.1016/j.jtice.2021.03.041
22. Pedebos MES Removal of Rhodamine B dye by adsorption onto an eco-friendly zeolite and machine learning modeling J. Photochem. Photobiol. A Chem. 2024 449 115404 10.1016/j.jphotochem.2023.115404
Pedebos, M. E. S. et al. Removal of Rhodamine B dye by adsorption onto an eco-friendly zeolite and machine learning modeling. J. Photochem. Photobiol. A Chem. 449, 115404 (2024).10.1016/j.jphotochem.2023.115404
23. Dalmaz A Sivrikaya Özak S Methylene blue dye efficient removal using activated carbon developed from waste cigarette butts: Adsorption, thermodynamic and kinetics Fuel 2024 372 132151 10.1016/j.fuel.2024.132151
Dalmaz, A. & Sivrikaya Özak, S. Methylene blue dye efficient removal using activated carbon developed from waste cigarette butts: Adsorption, thermodynamic and kinetics. Fuel 372, 132151 (2024).10.1016/j.fuel.2024.132151
24. Rasilingwani TE Gumbo JR Masindi V Foteinis S Removal of Congo red dye from industrial effluents using metal oxide-clay nanocomposites: Insight into adsorption and precipitation mechanisms Water Resour. Ind. 2024 31 100253 10.1016/j.wri.2024.100253
Rasilingwani, T. E., Gumbo, J. R., Masindi, V. & Foteinis, S. Removal of Congo red dye from industrial effluents using metal oxide-clay nanocomposites: Insight into adsorption and precipitation mechanisms. Water Resour. Ind. 31, 100253 (2024).10.1016/j.wri.2024.100253
25. Ciğeroğlu Z Clay-based nanomaterials and their adsorptive removal efficiency for dyes and antibiotics: A review Mater. Today Sustain. 2024 26 100735
Ciğeroğlu, Z. et al. Clay-based nanomaterials and their adsorptive removal efficiency for dyes and antibiotics: A review. Mater. Today Sustain. 26, 100735 (2024).
26. Akoulih M Electrocoagulation-based AZO DYE (P4R) removal rate prediction model using deep learning Proc. Comput. Sci. 2024 236 51 58 10.1016/j.procs.2024.05.003
Akoulih, M. et al. Electrocoagulation-based AZO DYE (P4R) removal rate prediction model using deep learning. Proc. Comput. Sci. 236, 51–58 (2024).10.1016/j.procs.2024.05.003
27. Tanti M Patel UD A synergistic application of simultaneous electrocoagulation-electrooxidation process for the treatment of floor-wash wastewater containing Rhodamine B dye J. Water Process Eng. 2023 56 104290 10.1016/j.jwpe.2023.104290
Tanti, M. & Patel, U. D. A synergistic application of simultaneous electrocoagulation-electrooxidation process for the treatment of floor-wash wastewater containing Rhodamine B dye. J. Water Process Eng. 56, 104290 (2023).10.1016/j.jwpe.2023.104290
28. Talaiekhozani A Reza Mosayebi M Fulazzaky MA Eskandari Z Sanayee R Combination of TiO2 microreactor and electroflotation for organic pollutant removal from textile dyeing industry wastewater Alex. Eng. J. 2020 59 549 563 10.1016/j.aej.2020.01.052
Talaiekhozani, A., Reza Mosayebi, M., Fulazzaky, M. A., Eskandari, Z. & Sanayee, R. Combination of TiO2 microreactor and electroflotation for organic pollutant removal from textile dyeing industry wastewater. Alex. Eng. J. 59, 549–563 (2020).10.1016/j.aej.2020.01.052
29. Suliman ZA Mecha AC Mwasiagi JI Effect of TiO2/Fe2O3 nanopowder synthesis method on visible light photocatalytic degradation of reactive blue dye Heliyon 2024 10 e29648 10.1016/j.heliyon.2024.e29648 38681613
Suliman, Z. A., Mecha, A. C. & Mwasiagi, J. I. Effect of TiO2/Fe2O3 nanopowder synthesis method on visible light photocatalytic degradation of reactive blue dye. Heliyon 10, e29648 (2024).38681613 10.1016/j.heliyon.2024.e29648
30. Zinatloo-Ajabshir S Novel rod-like [Cu(phen)2(OAc)]·PF6 complex for high-performance visible-light-driven photocatalytic degradation of hazardous organic dyes: DFT approach, Hirshfeld and fingerprint plot analysis J. Environ. Manag. 2024 350 119545 10.1016/j.jenvman.2023.119545
Zinatloo-Ajabshir, S. et al. Novel rod-like [Cu(phen)2(OAc)]·PF6 complex for high-performance visible-light-driven photocatalytic degradation of hazardous organic dyes: DFT approach, Hirshfeld and fingerprint plot analysis. J. Environ. Manag. 350, 119545 (2024).10.1016/j.jenvman.2023.119545
31. Zinatloo-Ajabshir S Morassaei MS Salavati-Niasari M Eco-friendly synthesis of Nd 2 Sn 2 O 7-based nanostructure materials using grape juice as green fuel as photocatalyst for the degradation of erythrosine Compos. Part B Eng. 2019 167 643 653 10.1016/j.compositesb.2019.03.045
Zinatloo-Ajabshir, S., Morassaei, M. S. & Salavati-Niasari, M. Eco-friendly synthesis of Nd 2 Sn 2 O 7-based nanostructure materials using grape juice as green fuel as photocatalyst for the degradation of erythrosine. Compos. Part B Eng. 167, 643–653 (2019).10.1016/j.compositesb.2019.03.045
32. Zinatloo-Ajabshir S Morassaei MS Amiri O Salavati-Niasari M Green synthesis of dysprosium stannate nanoparticles using Ficus carica extract as photocatalyst for the degradation of organic pollutants under visible irradiation Ceram. Int. 2020 46 6095 6107 10.1016/j.ceramint.2019.11.072
Zinatloo-Ajabshir, S., Morassaei, M. S., Amiri, O. & Salavati-Niasari, M. Green synthesis of dysprosium stannate nanoparticles using Ficus carica extract as photocatalyst for the degradation of organic pollutants under visible irradiation. Ceram. Int. 46, 6095–6107 (2020).10.1016/j.ceramint.2019.11.072
33. Zinatloo-Ajabshir S Mortazavi-Derazkola S Salavati-Niasari M Schiff-base hydrothermal synthesis and characterization of Nd2O3 nanostructures for effective photocatalytic degradation of eriochrome black T dye as water contaminant J. Mater. Sci. Mater. Electron. 2017 28 17849 17859 10.1007/s10854-017-7726-4
Zinatloo-Ajabshir, S., Mortazavi-Derazkola, S. & Salavati-Niasari, M. Schiff-base hydrothermal synthesis and characterization of Nd2O3 nanostructures for effective photocatalytic degradation of eriochrome black T dye as water contaminant. J. Mater. Sci. Mater. Electron. 28, 17849–17859 (2017).10.1007/s10854-017-7726-4
34. Zinatloo-Ajabshir S Salavati-Niasari M Preparation of nanocrystalline cubic ZrO2 with different shapes via a simple precipitation approach J. Mater. Sci. Mater. Electron. 2016 27 3918 3928 10.1007/s10854-015-4243-1
Zinatloo-Ajabshir, S. & Salavati-Niasari, M. Preparation of nanocrystalline cubic ZrO2 with different shapes via a simple precipitation approach. J. Mater. Sci. Mater. Electron. 27, 3918–3928 (2016).10.1007/s10854-015-4243-1
35. Zinatloo-Ajabshir S Mortazavi-Derazkola S Salavati-Niasari M Nd2O3–SiO2 nanocomposites: A simple sonochemical preparation, characterization and photocatalytic activity Ultrason. Sonochem. 2018 42 171 182 10.1016/j.ultsonch.2017.11.026 29429658
Zinatloo-Ajabshir, S., Mortazavi-Derazkola, S. & Salavati-Niasari, M. Nd2O3–SiO2 nanocomposites: A simple sonochemical preparation, characterization and photocatalytic activity. Ultrason. Sonochem. 42, 171–182 (2018).29429658 10.1016/j.ultsonch.2017.11.026
36. Zinatloo-Ajabshir S Mortazavi-Derazkola S Salavati-Niasari M Preparation, characterization and photocatalytic degradation of methyl violet pollutant of holmium oxide nanostructures prepared through a facile precipitation method J. Mol. Liq. 2017 231 306 313 10.1016/j.molliq.2017.02.002
Zinatloo-Ajabshir, S., Mortazavi-Derazkola, S. & Salavati-Niasari, M. Preparation, characterization and photocatalytic degradation of methyl violet pollutant of holmium oxide nanostructures prepared through a facile precipitation method. J. Mol. Liq. 231, 306–313 (2017).10.1016/j.molliq.2017.02.002
37. Zinatloo-Ajabshir S Morassaei MS Salavati-Niasari M Nd2Sn2O7 nanostructures as highly efficient visible light photocatalyst: Green synthesis using pomegranate juice and characterization J. Clean. Prod. 2018 198 11 18 10.1016/j.jclepro.2018.07.031
Zinatloo-Ajabshir, S., Morassaei, M. S. & Salavati-Niasari, M. Nd2Sn2O7 nanostructures as highly efficient visible light photocatalyst: Green synthesis using pomegranate juice and characterization. J. Clean. Prod. 198, 11–18 (2018).10.1016/j.jclepro.2018.07.031
38. Khan I Shah T Tariq MR Ahmad M Zhang B Understanding the toxicity of trinitrophenol and promising decontamination strategies for its neutralization: Challenges and future perspectives J. Environ. Chem. Eng. 2024 12 112720 10.1016/j.jece.2024.112720
Khan, I., Shah, T., Tariq, M. R., Ahmad, M. & Zhang, B. Understanding the toxicity of trinitrophenol and promising decontamination strategies for its neutralization: Challenges and future perspectives. J. Environ. Chem. Eng. 12, 112720 (2024).10.1016/j.jece.2024.112720
39. Khan N Khan I Zada N Saeed K Adsorption of Cu (II) ion through functionalized nylon 66 and their utilization as photocatalyst for the photodegradation of eriochrome black t dye in aqueous medium Fibers Polym. 2022 23 1266 1274 10.1007/s12221-022-4214-0
Khan, N., Khan, I., Zada, N. & Saeed, K. Adsorption of Cu (II) ion through functionalized nylon 66 and their utilization as photocatalyst for the photodegradation of eriochrome black t dye in aqueous medium. Fibers Polym. 23, 1266–1274 (2022).10.1007/s12221-022-4214-0
40. Purnomo AS Anionic dye removal by immobilized bacteria into alginate-polyvinyl alcohol-bentonite matrix Heliyon 2024 10 e27871 10.1016/j.heliyon.2024.e27871 38533018
Purnomo, A. S. et al. Anionic dye removal by immobilized bacteria into alginate-polyvinyl alcohol-bentonite matrix. Heliyon 10, e27871 (2024).38533018 10.1016/j.heliyon.2024.e27871
41. Ting ASY Cheng CKW Santiago KAA Decolourization of malachite green dye by endolichenic fungi from the lichen Usnea sp.: A novel study on their dye removal potential J. King Saud Univ. Sci. 2021 33 101579 10.1016/j.jksus.2021.101579
Ting, A. S. Y., Cheng, C. K. W. & Santiago, K. A. A. Decolourization of malachite green dye by endolichenic fungi from the lichen Usnea sp.: A novel study on their dye removal potential. J. King Saud Univ. Sci. 33, 101579 (2021).10.1016/j.jksus.2021.101579
42. Agha HM Enhancing cationic dye removal via biocomposite formation between chitosan and food grade algae: Optimization of algae loading and adsorption parameters Int. J. Biol. Macromol. 2024 258 128792 10.1016/j.ijbiomac.2023.128792 38110162
Agha, H. M. et al. Enhancing cationic dye removal via biocomposite formation between chitosan and food grade algae: Optimization of algae loading and adsorption parameters. Int. J. Biol. Macromol. 258, 128792 (2024).38110162 10.1016/j.ijbiomac.2023.128792
43. Nyakairu GWA Synthesis, characterization and application of Zeolite/Bi2O3 nanocomposite in removal of Rhodamine B dye from wastewater Clean. Water 2024 1 100004 10.1016/j.clwat.2024.100004
Nyakairu, G. W. A. et al. Synthesis, characterization and application of Zeolite/Bi2O3 nanocomposite in removal of Rhodamine B dye from wastewater. Clean. Water 1, 100004 (2024).10.1016/j.clwat.2024.100004
44. Alghanmi RM Abdelrahman EA Simple production and characterization of ZnO/MgO nanocomposite as a highly effective adsorbent for eliminating congo red dye from water-based solutions Inorg. Chem. Commun. 2024 161 112137 10.1016/j.inoche.2024.112137
Alghanmi, R. M. & Abdelrahman, E. A. Simple production and characterization of ZnO/MgO nanocomposite as a highly effective adsorbent for eliminating congo red dye from water-based solutions. Inorg. Chem. Commun. 161, 112137 (2024).10.1016/j.inoche.2024.112137
45. Al-Kadhi NS Calcium ferrite nanoparticles: A simple synthesis approach for the effective disposal of congo red dye from aqueous environments Inorganics 2024 12 69 10.3390/inorganics12030069
Al-Kadhi, N. S. et al. Calcium ferrite nanoparticles: A simple synthesis approach for the effective disposal of congo red dye from aqueous environments. Inorganics 12, 69 (2024).10.3390/inorganics12030069
46. Yousefi SR Alshamsi HA Amiri O Salavati-Niasari M Synthesis, characterization and application of Co/Co3O4 nanocomposites as an effective photocatalyst for discoloration of organic dye contaminants in wastewater and antibacterial properties J. Mol. Liq. 2021 337 116405 10.1016/j.molliq.2021.116405
Yousefi, S. R., Alshamsi, H. A., Amiri, O. & Salavati-Niasari, M. Synthesis, characterization and application of Co/Co3O4 nanocomposites as an effective photocatalyst for discoloration of organic dye contaminants in wastewater and antibacterial properties. J. Mol. Liq. 337, 116405 (2021).10.1016/j.molliq.2021.116405
47. Heidari-Asil SA Magnetically recyclable ZnCo2O4/Co3O4 nano-photocatalyst: Green combustion preparation, characterization and its application for enhanced degradation of contaminated water under sunlight Int. J. Hydrogen Energy 2022 47 16852 16861 10.1016/j.ijhydene.2022.03.157
Heidari-Asil, S. A. et al. Magnetically recyclable ZnCo2O4/Co3O4 nano-photocatalyst: Green combustion preparation, characterization and its application for enhanced degradation of contaminated water under sunlight. Int. J. Hydrogen Energy 47, 16852–16861 (2022).10.1016/j.ijhydene.2022.03.157
48. Alwan Altaa SH Habeeb Alshamsi HA Jasim Al-Hayder LS Synthesis and characterization of rgo/co3o4 composite as nanoadsorbent for rhodamine 6g dye removal Desalin. Water Treat. 2018 114 320 331 10.5004/dwt.2018.22351
Alwan Altaa, S. H., Habeeb Alshamsi, H. A. & Jasim Al-Hayder, L. S. Synthesis and characterization of rgo/co3o4 composite as nanoadsorbent for rhodamine 6g dye removal. Desalin. Water Treat. 114, 320–331 (2018).10.5004/dwt.2018.22351
49. Uddin MK Baig U Synthesis of Co3O4 nanoparticles and their performance towards methyl orange dye removal: Characterisation, adsorption and response surface methodology J. Clean. Prod. 2019 211 1141 1153 10.1016/j.jclepro.2018.11.232
Uddin, M. K. & Baig, U. Synthesis of Co3O4 nanoparticles and their performance towards methyl orange dye removal: Characterisation, adsorption and response surface methodology. J. Clean. Prod. 211, 1141–1153 (2019).10.1016/j.jclepro.2018.11.232
50. Al-Wasidi AS Hegazey RM Abdelrahman EA Efficient removal of methylene blue dye from aqueous media using facilely synthesized magnesium borate/magnesium oxide nanostructures Molecules 2024 29 3392 10.3390/molecules29143392 39064970
Al-Wasidi, A. S., Hegazey, R. M. & Abdelrahman, E. A. Efficient removal of methylene blue dye from aqueous media using facilely synthesized magnesium borate/magnesium oxide nanostructures. Molecules 29, 3392 (2024).39064970 10.3390/molecules29143392
51. Alhalili Z Abdelrahman EA Facile synthesis and characterization of manganese ferrite nanoparticles for the successful removal of safranine T dye from aqueous solutions Inorganics 2024 12 30 10.3390/inorganics12010030
Alhalili, Z. & Abdelrahman, E. A. Facile synthesis and characterization of manganese ferrite nanoparticles for the successful removal of safranine T dye from aqueous solutions. Inorganics 12, 30 (2024).10.3390/inorganics12010030
52. Chinoune K Adsorption behavior of MB dye on alginate-sepiolite biocomposite beads: Adsorption, kinetics, and modeling Inorg. Chem. Commun. 2024 165 112558 10.1016/j.inoche.2024.112558
Chinoune, K. et al. Adsorption behavior of MB dye on alginate-sepiolite biocomposite beads: Adsorption, kinetics, and modeling. Inorg. Chem. Commun. 165, 112558 (2024).10.1016/j.inoche.2024.112558
53. Saadi AS Efficient synthesis of magnetic activated carbon from oak pericarp for enhanced dye adsorption: A one-step approach Desalin. Water Treat. 2024 319 100420 10.1016/j.dwt.2024.100420
Saadi, A. S. et al. Efficient synthesis of magnetic activated carbon from oak pericarp for enhanced dye adsorption: A one-step approach. Desalin. Water Treat. 319, 100420 (2024).10.1016/j.dwt.2024.100420
54. Nabieh KA Mortada WI Helmy TE Kenawy IMM Abou El-Reash YG Chemically modified rice husk as an effective adsorbent for removal of palladium ions Heliyon 2021 7 e06062 10.1016/j.heliyon.2021.e06062 33537487
Nabieh, K. A., Mortada, W. I., Helmy, T. E., Kenawy, I. M. M. & Abou El-Reash, Y. G. Chemically modified rice husk as an effective adsorbent for removal of palladium ions. Heliyon 7, e06062 (2021).33537487 10.1016/j.heliyon.2021.e06062
55. Al-Wasidi AS AlReshaidan S Enhanced removal of rhodamine b dye from aqueous media via adsorption on facilely synthesized zinc ferrite nanoparticles Inorganics 2024 12 191 10.3390/inorganics12070191
Al-Wasidi, A. S. & AlReshaidan, S. Enhanced removal of rhodamine b dye from aqueous media via adsorption on facilely synthesized zinc ferrite nanoparticles. Inorganics 12, 191 (2024).10.3390/inorganics12070191
56. Abdelrahman EA Al-Farraj ES Facile synthesis and characterizations of mixed metal oxide nanoparticles for the efficient photocatalytic degradation of rhodamine B and Congo red dyes Nanomaterials 2022 12 3992 10.3390/nano12223992 36432277
Abdelrahman, E. A. & Al-Farraj, E. S. Facile synthesis and characterizations of mixed metal oxide nanoparticles for the efficient photocatalytic degradation of rhodamine B and Congo red dyes. Nanomaterials 12, 3992 (2022).36432277 10.3390/nano12223992
57. Almehizia AA Facile synthesis of copper carbonate/cobalt carbonate/manganese carbonate and copper oxide/cobalt manganese oxide/manganese oxide as novel nanocomposites for efficient photocatalytic degradation of crystal violet dye Int. J. Environ. Anal. Chem. 2022 10.1080/03067319.2022.2121164
Almehizia, A. A. et al. Facile synthesis of copper carbonate/cobalt carbonate/manganese carbonate and copper oxide/cobalt manganese oxide/manganese oxide as novel nanocomposites for efficient photocatalytic degradation of crystal violet dye. Int. J. Environ. Anal. Chem.10.1080/03067319.2022.2121164 (2022) (in press).10.1080/03067319.2022.2121164
58. Abdelrahman EA Facile synthesis of MgO/CuO and MgO/Cu3MgO4 binary nanocomposites as promising adsorbents for the disposal of Zn(II) ions J. Inorg. Organomet. Polym. Mater. 2024 34 266 281 10.1007/s10904-023-02826-2
Abdelrahman, E. A. et al. Facile synthesis of MgO/CuO and MgO/Cu3MgO4 binary nanocomposites as promising adsorbents for the disposal of Zn(II) ions. J. Inorg. Organomet. Polym. Mater. 34, 266–281 (2024).10.1007/s10904-023-02826-2
59. Al-Wasidi AS Facile synthesis and characterisation of Mn0.5Zn0.5Fe2O4/Fe2O3 as a novel nanocomposite for studying analytical parameters affecting on photocatalytic degradation of basic fuchsin dye Int. J. Environ. Anal. Chem. 2022 10.1080/03067319.2022.2153044
Al-Wasidi, A. S. et al. Facile synthesis and characterisation of Mn0.5Zn0.5Fe2O4/Fe2O3 as a novel nanocomposite for studying analytical parameters affecting on photocatalytic degradation of basic fuchsin dye. Int. J. Environ. Anal. Chem.10.1080/03067319.2022.2153044 (2022).10.1080/03067319.2022.2153044
60. Al-Wasidi AS Khairy M Abdulkhair BY Abdelrahman EA Efficient disposal of basic fuchsin dye from aqueous media using ZrO2/MgMn2O4/Mg(Mg0.333Mn1.333)O4 as a novel and facilely synthesized nanocomposite Inorganics 2023 11 363 10.3390/inorganics11090363
Al-Wasidi, A. S., Khairy, M., Abdulkhair, B. Y. & Abdelrahman, E. A. Efficient disposal of basic fuchsin dye from aqueous media using ZrO2/MgMn2O4/Mg(Mg0.333Mn1.333)O4 as a novel and facilely synthesized nanocomposite. Inorganics 11, 363 (2023).10.3390/inorganics11090363
61. Abdelrahman EA Efficient disposal of rhodamine 6G and acid orange 10 dyes from aqueous media using ZrO2/CdMn2O4/CdO as novel and facilely synthesized nanocomposites Inorganics 2023 11 333 10.3390/inorganics11080333
Abdelrahman, E. A. et al. Efficient disposal of rhodamine 6G and acid orange 10 dyes from aqueous media using ZrO2/CdMn2O4/CdO as novel and facilely synthesized nanocomposites. Inorganics 11, 333 (2023).10.3390/inorganics11080333
62. Al-Wasidi AS Abdelrahman EA Significant photocatalytic decomposition of malachite green dye in aqueous solutions utilizing facilely synthesized barium titanate nanoparticles Discov. Nano 2023 18 97 10.1186/s11671-023-03873-x 37507521
Al-Wasidi, A. S. & Abdelrahman, E. A. Significant photocatalytic decomposition of malachite green dye in aqueous solutions utilizing facilely synthesized barium titanate nanoparticles. Discov. Nano 18, 97 (2023).37507521 10.1186/s11671-023-03873-x
63. Nulu V Nulu A Sohn KY Room-temperature facile synthesis of Co3O4 nanoflakes as anode material for Li-ion rechargeable batteries Int. J. Electrochem. Sci. 2018 13 2069 2079 10.20964/2018.02.73
Nulu, V., Nulu, A. & Sohn, K. Y. Room-temperature facile synthesis of Co3O4 nanoflakes as anode material for Li-ion rechargeable batteries. Int. J. Electrochem. Sci. 13, 2069–2079 (2018).10.20964/2018.02.73
64. Singh V Pandey V Singh VK Majhi MR Synthesis and characterization of single-phase magnesium borate nanorod via solution reaction cum sintering process Ceram. Int. 2023 49 27086 27093 10.1016/j.ceramint.2023.05.253
Singh, V., Pandey, V., Singh, V. K. & Majhi, M. R. Synthesis and characterization of single-phase magnesium borate nanorod via solution reaction cum sintering process. Ceram. Int. 49, 27086–27093 (2023).10.1016/j.ceramint.2023.05.253
65. Ozerova AM Cobalt borate catalysts for hydrogen production via hydrolysis of sodium borohydride J. Alloys Compd. 2012 513 266 272 10.1016/j.jallcom.2011.10.033
Ozerova, A. M. et al. Cobalt borate catalysts for hydrogen production via hydrolysis of sodium borohydride. J. Alloys Compd. 513, 266–272 (2012).10.1016/j.jallcom.2011.10.033
66. Alhalili Z Abdelrahman EA Efficient removal of Zn(II) ions from aqueous media using a facilely synthesized nanocomposite based on chitosan Schiff base Sci. Rep. 2024 14 1 15 10.1038/s41598-024-68745-5 38167627
Alhalili, Z. & Abdelrahman, E. A. Efficient removal of Zn(II) ions from aqueous media using a facilely synthesized nanocomposite based on chitosan Schiff base. Sci. Rep. 14, 1–15 (2024).38167627 10.1038/s41598-024-68745-5
67. Al-wasidi AS Shah RK Abdelrahman EA Facile synthesis of CuFe2O4 nanoparticles for efficient removal of acid blue 113 and malachite green dyes from aqueous media Inorganics 2024 12 143 10.3390/inorganics12060143
Al-wasidi, A. S., Shah, R. K. & Abdelrahman, E. A. Facile synthesis of CuFe2O4 nanoparticles for efficient removal of acid blue 113 and malachite green dyes from aqueous media. Inorganics 12, 143 (2024).10.3390/inorganics12060143
68. Al-Wasidi AS Abdelrahman EA Functionalization of strontium ferrite nanoparticles with novel chitosan-schiff base ligand for efficient removal of Pb(II) ions from aqueous media Inorganics 2024 12 148 10.3390/inorganics12060148
Al-Wasidi, A. S. & Abdelrahman, E. A. Functionalization of strontium ferrite nanoparticles with novel chitosan-schiff base ligand for efficient removal of Pb(II) ions from aqueous media. Inorganics 12, 148 (2024).10.3390/inorganics12060148
69. Shafeeq K Functionalization of calcium silicate/sodium calcium silicate nanostructures with chitosan and chitosan/glutaraldehyde as novel nanocomposites for the efficient adsorption of Cd(II) and Cu(II) ions from aqueous solutions Silicon 2024 16 1713 1730 10.1007/s12633-023-02793-w
Shafeeq, K. et al. Functionalization of calcium silicate/sodium calcium silicate nanostructures with chitosan and chitosan/glutaraldehyde as novel nanocomposites for the efficient adsorption of Cd(II) and Cu(II) ions from aqueous solutions. Silicon 16, 1713–1730 (2024).10.1007/s12633-023-02793-w
70. Al-Kadhi NS A facile sol-gel synthesis and characterization of MgCO3/MnCO3 and MgMn2O4/Mn2O3 novel nanostructures with remarkably high adsorption activity toward eriochrome black T dye J. Inorg. Organomet. Polym. Mater. 2023 33 2046 2057 10.1007/s10904-023-02660-6
Al-Kadhi, N. S. et al. A facile sol-gel synthesis and characterization of MgCO3/MnCO3 and MgMn2O4/Mn2O3 novel nanostructures with remarkably high adsorption activity toward eriochrome black T dye. J. Inorg. Organomet. Polym. Mater. 33, 2046–2057 (2023).10.1007/s10904-023-02660-6
71. Ahamad Z Nasar A Polypyrrole-decorated bentonite magnetic nanocomposite: A green approach for adsorption of anionic methyl orange and cationic crystal violet dyes from contaminated water Environ. Res. 2024 247 118193 10.1016/j.envres.2024.118193 38220086
Ahamad, Z. & Nasar, A. Polypyrrole-decorated bentonite magnetic nanocomposite: A green approach for adsorption of anionic methyl orange and cationic crystal violet dyes from contaminated water. Environ. Res. 247, 118193 (2024).38220086 10.1016/j.envres.2024.118193
72. Shirsath SR Patil AP Bhanvase BA Sonawane SH Ultrasonically prepared poly(acrylamide)-kaolin composite hydrogel for removal of crystal violet dye from wastewater J. Environ. Chem. Eng. 2015 3 1152 1162 10.1016/j.jece.2015.04.016
Shirsath, S. R., Patil, A. P., Bhanvase, B. A. & Sonawane, S. H. Ultrasonically prepared poly(acrylamide)-kaolin composite hydrogel for removal of crystal violet dye from wastewater. J. Environ. Chem. Eng. 3, 1152–1162 (2015).10.1016/j.jece.2015.04.016
73. Sarabadan M Bashiri H Mousavi SM Removal of crystal violet dye by an efficient and low cost adsorbent: Modeling, kinetic, equilibrium and thermodynamic studies Korean J. Chem. Eng. 2019 36 1575 1586 10.1007/s11814-019-0356-1
Sarabadan, M., Bashiri, H. & Mousavi, S. M. Removal of crystal violet dye by an efficient and low cost adsorbent: Modeling, kinetic, equilibrium and thermodynamic studies. Korean J. Chem. Eng. 36, 1575–1586 (2019).10.1007/s11814-019-0356-1
74. Gholami M Vardini MT Mahdavinia GR Investigation of the effect of magnetic particles on the Crystal Violet adsorption onto a novel nanocomposite based on κ-carrageenan-g-poly(methacrylic acid) Carbohydr. Polym. 2016 136 772 781 10.1016/j.carbpol.2015.09.044 26572412
Gholami, M., Vardini, M. T. & Mahdavinia, G. R. Investigation of the effect of magnetic particles on the Crystal Violet adsorption onto a novel nanocomposite based on κ-carrageenan-g-poly(methacrylic acid). Carbohydr. Polym. 136, 772–781 (2016).26572412 10.1016/j.carbpol.2015.09.044
75. Muthukumaran C Sivakumar VM Thirumarimurugan M Adsorption isotherms and kinetic studies of crystal violet dye removal from aqueous solution using surfactant modified magnetic nanoadsorbent J. Taiwan Inst. Chem. Eng. 2016 63 354 362 10.1016/j.jtice.2016.03.034
Muthukumaran, C., Sivakumar, V. M. & Thirumarimurugan, M. Adsorption isotherms and kinetic studies of crystal violet dye removal from aqueous solution using surfactant modified magnetic nanoadsorbent. J. Taiwan Inst. Chem. Eng. 63, 354–362 (2016).10.1016/j.jtice.2016.03.034
76. Gupta S Prajapati A Kumar A Acharya S Synthesis of silica aerogel and its application for removal of crystal violet dye by adsorption Watershed Ecol. Environ. 2023 5 241 254 10.1016/j.wsee.2023.10.003
Gupta, S., Prajapati, A., Kumar, A. & Acharya, S. Synthesis of silica aerogel and its application for removal of crystal violet dye by adsorption. Watershed Ecol. Environ. 5, 241–254 (2023).10.1016/j.wsee.2023.10.003
77. Rath J Green synthesis of silver nanoparticles decorated on graphene oxide for crystal violet dye removal Diam. Relat. Mater. 2024 146 111192 10.1016/j.diamond.2024.111192
Rath, J. et al. Green synthesis of silver nanoparticles decorated on graphene oxide for crystal violet dye removal. Diam. Relat. Mater. 146, 111192 (2024).10.1016/j.diamond.2024.111192
78. Foroutan R Peighambardoust SJ Peighambardoust SH Pateiro M Lorenzo JM Adsorption of crystal violet dye using activated carbon of lemon wood and activated carbon/Fe3O4 magnetic nanocomposite from aqueous solutions: A kinetic, equilibrium and thermodynamic study Molecules 2021 26 1 19 10.3390/molecules26082241
Foroutan, R., Peighambardoust, S. J., Peighambardoust, S. H., Pateiro, M. & Lorenzo, J. M. Adsorption of crystal violet dye using activated carbon of lemon wood and activated carbon/Fe3O4 magnetic nanocomposite from aqueous solutions: A kinetic, equilibrium and thermodynamic study. Molecules 26, 1–19 (2021).10.3390/molecules26082241
79. Chakraborty S Study on isotherm, kinetics, and thermodynamics of adsorption of crystal violet dye by calcium oxide modified fly ash Environ. Eng. Res. 2021 26 1 9
Chakraborty, S. et al. Study on isotherm, kinetics, and thermodynamics of adsorption of crystal violet dye by calcium oxide modified fly ash. Environ. Eng. Res. 26, 1–9 (2021).
80. Albo Hay Allah MA Ibrahim HK Alshamsi HA Radhi Saud H Eco-friendly synthesis of biochar supported with zinc oxide as a heterogeneous catalyst for photocatalytic decontamination of Rhodamine B under sunlight illumination J. Photochem. Photobiol. A Chem. 2024 449 115413 10.1016/j.jphotochem.2023.115413
Albo Hay Allah, M. A., Ibrahim, H. K., Alshamsi, H. A. & Radhi Saud, H. Eco-friendly synthesis of biochar supported with zinc oxide as a heterogeneous catalyst for photocatalytic decontamination of Rhodamine B under sunlight illumination. J. Photochem. Photobiol. A Chem. 449, 115413 (2024).10.1016/j.jphotochem.2023.115413
