A novel approach for immobilizing Ag/ZnO nanorods on a glass substrate: Application in solar light-driven degradation of micropollutants in water

One of the main challenges in applying photocatalysts for water treatment is the complex separation and recycling process. In this study, we developed highly stable, porous zinc oxide nanorods (ZnO NRs) immobilized on glass vials using a solvent exchange process (SEP) and hydrothermal calcination. Key parameters, including oleic acid concentration and hydrothermal growth time, were optimized to maximize the active surface area, significantly enhancing photodegradation performance. Under the best conditions, ZnO NRs-coated vials achieved nearly 100% degradation of sulfamethoxazole (SMX) in 10 h of simulated solar irradiation. Depositing silver nanoparticles on the surface of ZnO NRs (Ag/ZnO NRs) further improved performance, reducing degradation time to 4 h and increasing photocatalyst stability. The Ag/ZnO NRs-coated vials, optimized with an Ag precursor concentration of 0.05 M, also demonstrated high degradation rates ($>$99%) for eight organic micropollutants at environmentally relevant concentrations over multiple reuse cycles and with minimal metal leaching. This study presents an innovative, tunable method for immobilizing photocatalysts on glass substrates, offering high surface area, excellent photocatalytic activity, and mechanical properties, making it highly suitable for water treatment applications.