Water treatment through photocatalysts has become an important topic regarding environmental protection. In the present study, silver and TiO₂ (Ag/TiO₂) composites for photocatalysts were effectively synthesized by adopting the template induced method. The prepared samples were characterized using XRD, FTIR spectroscopy, SEM, and EDX. The constructed samples’ particle size and shape were evaluated using a SEM, and the XRD patterns showed anatase crystalline phases. Their morphologies were controllable with changing concentration of reactants and calcination temperature. The synthesized composites act as catalyst in the degradation of methylene blue (MB) and reduction of Cr(VI) to Cr(III) under solar irradiation. In both of these activities, the best result has been shown by the 0.01 Ag/TiO₂ composite. Methanol is used as the hole scavenger in the reduction of Cr(VI) to Cr(III). While the pH factor is important in the photocatalytic reduction of Cr(VI) to Cr(III). According to observations, S. macrospora and S. maydis were each subject to 0.01 Ag/TiO₂ nanocomposites maximum antifungal activity, which was 38.4 mm and 34.3 mm, respectively. The outcomes demonstrate that both photocatalytic and antifungal properties are effectively displayed by the constructed material.

Nanosized Ni ferrite has been prepared by an ecofriendly green synthesis approach based on the self-combustion method. In this route, the egg white as a green fuel was employed with two different amounts (3 and 10 mL). The XRD results display the formation of a stoichiometric NiFe₂O₄-type inverse spinel structure with a lattice parameter located at 0.8284 nm and 0.8322 nm. Additionally, the nickel ferrites’ typical crystallite size, as synthesized, ranged between 4 and 18 nm. Indicating the development of ferrite material, FTIR analysis shows two distinctive vibrational modes around 600 cm⁻¹ and 400 cm⁻¹. TEM measurements show the formation of nanosized particles with semispherical-type structure and some agglomerations. As the egg white concentration rises, the surface area, total pore volume, and mean pore radius of the material, as prepared, all decrease, and according to the surface area parameters discovered using BET analysis. Based on VSM analysis, the values of saturation magnetization are 6.6589 emu/g and 37.727 emu/g, whereas the coercivity are 159.15 G and 113.74 G. The as-synthesized Ni ferrites fit into the pseudo-single domain predicated by the squareness values (0.1526 and 0.1824). It is mentioned that increasing the egg white content would promote the magnetization of NiFe₂O₄.

The pollution due to dyes from textile sector is one of the major issues faced worldwide. This study was focused on the removal of the reactive dye, Drimaren Turquoise CL-B using Schizophyllum commune, a white rot fungus (WRF) keeping in mind the current environmental conditions. Different parameters like pH, sources of carbon & nitrogen, temperature, concentration of dye and C/N ratio were used to investigate their effect on the process. Maximum dye removal of 95.45% was obtained at pH 4.5, temperature 35°C, inoculum size 3 mL, veratryl alcohol (mediator), glucose (carbon source) and ammonium nitrate (nitrogen source). The enzyme activity was determined by employing enzyme assay. Laccase and Lignin peroxidase (LiP) activity was low while Manganese peroxidase (MnP) activity was highest. Maximum bio-sorption was achieved at pH 1 and 313 K. The pseudo-2^nd-order kinetic model & Freundlich isotherm was best suited for the process of removal of dye. From these data, it is concluded that white rot fungus could possibly be the excellent biomaterial for elimination of synthetic dyes from wastewater.

Heterojunctions have proven to be effective catalysts for removing organic pollutants and heavy metals from wastewater. The following study is also about the formation of 2D heterojunction tellurium-doped zinc oxide composite with sulfur-doped graphitic carbon nitride (Te-ZnO@S-g-C₃N₄) by adopting a low-cost, simple, and ecofriendly coprecipitation technique. Thiourea was calcined to prepare S-g-C₃N₄ using the thermal degradation method. The characterization of synthesized photocatalysts was carried out by using SEM-EDX, FTIR, and XRD. The results obtained showed that the incorporation of tellurium caused an alteration in the wurtzite structure of ZnO. SEM-EDX analysis validated the purity of the synthesized samples due to the absence of any additional peaks. The decrease in the bandgap was also noted by the formation of composites. Using methylene blue as a reference dye, the UV-vis spectrophotometer was utilized to calculate the absorbance for photocatalytic degradation behavior. As a result of tellurium doping into the ZnO lattice, photocatalytic oxidation/reduction was improved, according to the results. 3Te-ZnO NPs showed the best degradation rate among dopant series, while an excellent overall degradation rate was noted by fabricated composite 3Te-ZnO@40S-g-C₃N₄. The best doped ZnO and composites were also used as sorbents for the abstraction of heavy metal (Cr(VI)) from water via adsorption. A definite rise in the removal efficiency percentage of chromium ions was observed by using these sorbents. The overall photo degradation rate and adsorption behavior noted were in ZnO<Te-ZnO<Te-ZnO@S-g-C₃N₄ order. When compared to ZnO, Te-ZnO, SCN, and Te-ZnO@40SCN, the 3Te-ZnO@40SCN NCs have outstanding antifungal potential. The improved dispersibility and interaction of 3Te-ZnO@40SCN with membrane and intracellular proteins of fungi may be the cause of the greater effect of Te-ZnO@40SCN.

The synthesis of a photo-catalyst with a narrow bandgap and efficient capability to degrade contaminants in the presence of sunlight is currently challenging but exciting. In this work, an efficient photocatalytic ternary nanocomposite g-C₃N₄/Cu@CdS has been synthesized successfully by using the co-precipitation method. The synthesized composite was then characterized by SEM, XRD studies, EDX analysis, and ultra-violet-visible (UV-VIS) spectroscopy. The catalytic efficiency for the methylene blue (MB) dye and drug degradation (ciprofloxacin) was assessed by UV-visible absorption spectra. Gram-positive and Gram-negative bacteria were used to test the fabrication composite’s antibacterial properties. Various compositions (1%, 3%, 5%, 7%, and 9%) of/Cu@CdS nanocomposite (NCs) and 20%, 30%, 40%, 50%, and 60% of g-C₃N₄ NCs were prepared. Results reveal that 5%Cu@CdS and 40%g-C₃N₄5%Cu@CdS showed maximum antibacterial activity and photocatalytic degradation of dye and drug. The X-ray pattern showed no remarkable change in doped and pristine CdS nanoparticles (NPs). The efficient photocatalytic degradation activity of the fabricated ternary nanocomposite against MB dye and ciprofloxacin an antibiotic drug makes it a viable contender for solving environmental problems.

A series of virgin and lithia-doped Ni ferrites was synthesized using egg-white-mediated combustion. Characterization of the investigated ferrites was performed using several techniques, specifically, X-ray Powder Diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and High-resolution transmission electron microscopy (HRTEM). XRD-based structural parameters were determined. A closer look at these characteristics reveals that lithia doping enhanced the nickel ferrite lattice constant (a), unit cell volume (V), stress (ε), microstrain (σ), and dislocation density (δ). It also enhanced the separation between magnetic ions (L_A and L_B), ionic radii (r_A, r_B), and bond lengths (A-O and B-O) between tetrahedral (A) and octahedral (B) locations. Furthermore, it enhanced the X-ray density (Dx) and crystallite size (d) of random spinel nickel ferrite displaying opposing patterns of behavior. FTIR-based functional groups of random spinel nickel ferrite were determined. HRTEM-based morphological properties of the synthesized ferrite were investigated. These characteristics of NiFe₂O₄ particles, such as their size, shape, and crystallinity, demonstrate that these manufactured particles are present at the nanoscale and that lithia doping caused shape modification of the particles. Additionally, the prepared ferrite’s surface area and total pore volume marginally increased after being treated with lithia, depending on the visibility of the grain boundaries. Last, but not least, as the dopant content was increased through a variety of methods, the magnetization of virgin nickel ferrite fell with a corresponding increase in coercivity. Uniaxial anisotropy, rather than cubic anisotropy, and antisite and cation excess defects developed in virgin and lithia-doped nickel ferrites because the squareness ratio (M_r/M_s) was less than 0.5. Small squareness values strongly recommend using the assessed ferrites in high-frequency applications.