Biosynthesized ZnO/ZnSnO₃ Nanocomposite Using Lemon Peel Extract for Enhanced Photocatalytic Degradation of Evans Blue Dye and Antibacterial Applications

This research outlines the development, comprehensive analysis, and assessment of the photocatalytic and antibacterial properties of ZnO/ZnSnO₃ nanocomposite (NC). The nanocomposite was synthesized using an eco-friendly green synthesis method with lemon peel extract. Techniques such as XRD, SEM, and FTIR verified the formation of dual-phase ZnO/ZnSnO₃ NC with an energy gap of ~ 1.9 eV and an average crystallite size of ~ 25.45 ± 1.24 nm. Photocatalytic degradation evaluated for Evans Blue (EB) dye under solar light indicated high degradation efficiency ~ 99.57% during 90 min, following pseudo-first-order kinetics with a rate constant ~ 0.11 min⁻¹. Furthermore, ZnO/ZnSnO₃ NC exhibited notable antibacterial potential with inhibition zones ranging from (10.0 ± 1.3 to 12.0 ± 0.5) mm for E. coli and (9.0 ± 0.8 to 14.0 ± 0.6) mm for P. aeruginosa, with improved activity against K. pneumoniae and S. aureus. The as-prepared NC exhibited significant antifungal activity against C. albicans with inhibition zones ~ 22.0 ± 0.3 mm. The results obtained categorized ZnO/ZnSnO₃ NC as a potential candidate to be utilized for environmental cleanup and wastewater treatment.