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In this study, NiZnFe 2 O 4 composite was synthesized using a sol-gel route and subjected to nonthermal plasma treatment for tailoring their cations' distribution and physicochemical, magnetic, and photocatalytic properties. Microwave plasma treatment was given to the composites for 60 min in support of postsynthesis sintering at 700 °C for 5 h. X-ray diffraction (XRD) analysis was conducted on pre- and postplasma-modified ferrite composites to identify phase-pure cubic spinel structure and cations' distribution. The cation distributions were measured from the ratio of XRD intensity peaks corresponding to (220), (311), (422) and (440) planes. The intensity ratio of plasma-treated ferrite composites decreased compared to that of pristine composites. The crystallite size and lattice constant were increased on plasma treatment of the composite. The morphological analysis showed nanoflower-like structures of the particles with an increased surface area in the plasma-treated composites. The plasma oxidation and sputtering effects caused a reduction in the nanoflower size. The energy bandgap increased with a decrease in particle size due to plasma treatment. The rhodamine B dye solution was then irradiated with a light source in the presence of the nanocomposites. The dye degradation efficiency of the composite photocatalyst increased from 80 to 96% after plasma treatment., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

This study used a simple coprecipitation method to produce pristine, silica-coated, and amino-functionalized CoFe 2 O 4 nanoadsorbents. Amino-functionalization was done to increase the active surface area and metal ion removal efficiency. Both pristine and functionalized adsorbents were employed to recover Pb(II), Zn(II), and Cu(II) ions from wastewater. The adsorption tests were performed by varying the initial concentration of metal ions and contact time at a fixed pH of 6.5. Atomic adsorption spectroscopy was utilized to detect the proportion of metals removed from water. Additionally, the pseudo-first-order, pseudo-second-order, Freundlich, and Langmuir models were employed to compute the kinetic and isothermic data from metal ion adsorption onto the adsorbents. The amino-functionalized adsorbent showed adsorption capacities of 277.008, 254.453, and 258.398 mg/g for Cu(II), Pb(II), and Zn(II) ions, respectively. According to the adsorption results, the Langmuir isotherm and the pseudo-second-order model best suit the data. The best fitting of the pseudo-second-order model with the data indicates that coordinative interactions between amino groups and metal ions are responsible for chemisorption. The metal ions bind with -NH 2 groups on the adsorbent surface through chelate bonds. Chelate bonds are extremely strong and stable, indicating the effectiveness of the CoFe 2 O 4 @SiO 2 -NH 2 adsorbent in adsorbing heavy-metal ions. The tested adsorbent exhibited good performance, batter stability, and good reusable values around 77, 81, and 76% for Cu(II), Pb(II), and Zn(II) ions, respectively, after five adsorption cycles., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Nonthermal plasma processing is a chemical-free and environmentally friendly technique to enhance the self-cleaning activity of nanoparticle-coated cotton fabrics. In this research, Sr-doped ZnO/carbon nanotube (CNT) photocatalysts, namely, S 10 ZC 2 , S 15 ZC 2 , and S 20 ZC 2 with different Sr doping concentrations, were synthesized using the sol-gel method and coated on plasma-functionalized fabric to perform the self-cleaning tests. The fabrics were treated with dielectric barrier discharge plasma in an open environment for 3 min to achieve a stable coating of nanoparticles. The energy band gap of the photocatalyst decreased with an increase in the level of Sr doping. The band gap of S 10 ZC 2 , S 15 ZC 2 , and S 20 ZC 2 photocatalysts was estimated to be 2.85, 2.78, and 2.5 eV, respectively. The hexagonal wurtzite structure of ZnO was observed on the fabric surface composited with CNTs and Sr. The S 20 ZC 2 photocatalyst showed better homogeneity and photocatalytic response on the fabric when compared with S 10 ZC 2 - and S 15 ZC 2 -coated fabrics. The S 20 ZC 2 photocatalyst showed 89% dye degradation efficiency after 4 h of light exposure in methylene blue solution, followed by S 15 ZC 2 (84%) and S 10 ZC 2 (80%) photocatalysts., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Even low concentrations of pollutants in water, particularly heavy metals, can significantly affect the ecosystem and human health. Adsorption has been determined to be one of the most effective techniques of removing pollution from wastewater among the various strategies. To remove heavy metals such as Zn 2+ and Pb 2+ , we prepared a silica-coated CuMgFe 2 O 4 magnetic adsorbent using sol-gel method and tested it for wastewater treatment. X-ray diffraction investigation validated the creation of cubic spinel structure, while morphological analysis showed that silica coating reduces the particle size but boosts the surface roughness of the nanoparticles and also reduces the agglomeration between particles. UV-visible spectroscopy indicates a rise in bandgap and magnetic characteristics analysis indicates low values of magnetization due to silica coating. The kinetic and isotherm parameters for heavy metal ions adsorption onto silica-coated Cu 0.50 Mg 0.50 Fe 2 O 4 nanoparticles are calculated by applying pseudo-first-order, pseudo-second-order, Langmuir and Freundlich models. Adsorption kinetics revealed that the pseudo-second-order and Langmuir models are the best fit to explain adsorption kinetics. Synthesized adsorbent revealed 92% and 97% removal efficiencies for Zn 2+ and Pb 2+ ions, respectively., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

This study investigated a ternary CdS/TiO 2 /g-C 3 N 4 heterojunction for degrading synthetic dyes and hydrogen production from aqueous media through visible light-initiated photocatalytic reactions. CdS, TiO 2 , and g-C 3 N 4 were combined in different mass ratios through a simple hydrothermal method to create CdS/TiO 2 /g-C 3 N 4 composite photocatalysts. The prepared heterojunction catalysts were investigated by using FTIR, XRD, EDX, SEM, and UV-visible spectroscopy analysis for their crystal structures, functional groups, elemental composition, microtopography, and optical properties. The rhodamine B dye was then degraded by using fully characterized photocatalysts. The maximum dye degradation efficiency of 99.4% was noted in these experiments. The evolution rate of hydrogen from the aqueous solution with the CdS/TiO 2 /g-C 3 N 4 photocatalyst remained 2910 μmol·h -1 ·g -1 , which is considerably higher than those of g-C 3 N 4 , CdS, CdS/g-C 3 N 4 , and g-C 3 N 4 /TiO 2 -catalyzed reactions. This study also proposes a photocatalytic activity mechanism for the tested ternary CdS/TiO 2 /g-C 3 N 4 heterojunctions., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

In this study, dual S-scheme ZnIn 2 S 4 -Al 2 O 3 -ZnO (ZIS-Al-Zn) heterojunctions were produced by a facile, low cost, and rapid combustion technique. These heterojunctions accelerated the photocatalytic hydrogen production due to the multi-channel-promoted separation of photocarriers. By optimizing the content of the components, the synthesized ZIS-Al-Zn composite with 20 wt% of ZnIn 2 S 4 and 30 wt% of Al 2 O 3 in the ZIS-Al-Zn composite demonstrated the highest hydrogen production rate of 54.2 mmol g -1 h -1 , which was nearly 11 and 8.30 times better than ZnO-Al 2 O 3 and ZnO-ZnIn 2 S 4 composites, respectively. The results of DRS, PL, EIS, LSV, and CV techniques showed the highest shift in the light absorption, rapid interfacial transfer, and quenched recombination of photocarriers over the ternary ZIS-Al-Zn composite than single and binary catalysts. The obtained results revealed the formation of a dual S-scheme mechanism of transfer of photocarriers in ZIS-Al-Zn heterojunctions, contributing to better hydrogen production efficiency. The optimized ZIS-Al-Zn composite also exhibited good stability and reusability., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)