In this study, we have touched on two goals of sustainable development, namely, the provision of clean water and sanitation and clean energy at acceptable prices, hoping for good health for all ages. A green economical method was used to prepare silver nanoparticles from chitosan biopolymer. AgNPs were fully characterized using UV–Vis, FTIR, XRD, HR-TEM, and EDX analysis. Different concentrations (0.02–0.18 g/L) of the nanoparticles were integrated into a mixture of heterogeneous nano photocatalysts TiO₂ and ZnO (1:1 weight ratio) under UV irradiation for the photocatalytic degradation of Acid Red 37 textile dye to obtain clean water. The kinetic description of the performed photocatalytic process was presented assuming a pseudo-first-order reaction. The data revealed that increasing the concentration of AgNPs in the catalytic mixture showed a high apparent rate constant (k_app) accompanied by an increase in the apparent quantum yield (%Q_app), followed by dye destruction after a very short time (t_0.5 = 3 min). Since the photocatalytic degradation process consumes electrical energy, the electrical energy per order (EE/O) was calculated, showing a low value of 20 kWh/m³/order, using 0.18 g/L AgNPs, indicating that the elicited photocatalytic degradation method is a sustainable one for the mineralization of the targeted dye.

The structural and electronic behavior of thiosemicarbazone (TSC)-based metal complexes of Mn (II), Fe (II), and Ni (II) have been investigated. The synthesized metal complexes were characterized using elemental analysis, magnetic susceptibility, molar conductivity, FTIR, and UV–Vis spectroscopy, the computational path helped with further structural investigation. The solubility test on the TSC and its complexes revealed their solubility in most organic solvents. DFT computational analysis was performed, and quantum reactivity parameters of the octahedral optimized complexes were calculated to describe the reactivity via the stability states of the synthesized complexes. FMOs map was generated to confirm similar findings and MEP analysis was applied to elaborate the important electrophilic and nucleophilic sites on the studied surfaces. Also, other important topological analyses such as electron localization function and reduced density gradient, to establish the favorable noncovalent interactions, were studied. In silico molecular docking approach was studied against the gram-positive bacteria Bacillus cereus to predict the potent inhibition behavior of the studied complexes. The findings summarized the inhibition prediction of the most interactive [NiL₂Cl₂], then [FeL₂Cl₂] complexes as confirmed by the binding energy values (− 7.1 kacl/mol and − 6.4 kacl/mol, respectively). Another In silico results, with gram-positive bacteria (S. aureus), estimated similar results of the experimental finding, where [MnL₂Cl₂] (− 9.2 kcal/mol) is the more effective predicted antibacterial inhibitor. Fluorescence microscopy was used to examine the inhibition of bacterial biofilm, and the DPPH assay was used to measure antioxidant activity, followed by an understanding of the behavior of the current complexes toward free radicals’ removal. The findings observed less aggregated bacterial strains covered with the studied complexes leading to less dense biofilm covering.