bio-inspired tio2 nanoparticles: green photocatalysts for azo dyes driven by uv-a

This study reports the green synthesis of titanium dioxide nanoparticles (tio₂ nps) using lansium domesticum correa (ldc) peel extract as a natural stabilizing and reducing agent. the synthesized tio₂ nps exhibited a band gap of 3.2 ev and a zeta potential of –47 mv, indicating strong colloidal stability. their photocatalytic performance was evaluated in the degradation of acid yellow 25 (ay25) under various light sources, where uv-a irradiation showed the highest activity. the effects of dye concentration, ph, catalyst dosage, and exposure time were systematically investigated. optimal conditions (0.1 g catalyst, 20 mg l^-1 ay25, ph 3, 240 min) resulted in 95% degradation efficiency, following pseudo first order kinetics (r² = 0.9932). reusability studies demonstrated stable performance across three cycles with efficiencies of 82%, 78%, and 73%. scavenger tests identified e⁻, •o₂⁻, •oh, and h⁺ as the main reactive species involved in degradation. these findings highlight the potential of green synthesized tio₂ nps as efficient, reusable photocatalysts for sustainable wastewater treatment and environmental remediation.