Ag/TiO2 photocatalytic synergistic persulfate activation for degradation of methyl orange

Ag/TiO₂ composite photocatalysts were synthesized using a sol-gel reduction method. Their crystal structures and chemical compositions were analyzed through techniques such as XRD and XPS, and their effects in the photocatalytic synergistic PMS system for the degradation of methyl orange were investigated. The results indicated that the Ag/TiO₂ composite photocatalyst was successfully synthesized, with the bandgap energy reduced from 3.23 eV to 3.07 eV. Under optimal conditions—specifically, a reaction time of 20 min, the use of an Ag/TiO₂-1% catalyst, the pH of 2.59, a catalyst dosage of 0.66 g/L, and a PMS dosage of 1.87 mM—the degradation rate of 100 mg/L of MO dye reached 95.83 %. Furthermore, the catalyst maintained a degradation rate of 90 % after five recycling cycles, demonstrating excellent stability and reusability. This study provides a valuable theoretical foundation for the development of efficient photocatalysts and highlights the potential of Ag/TiO₂ photocatalysts for practical applications.