Enhanced photodegradation performance based on the surface plasmon resonance effect of Ag/Ca2Al2SiO7:Pr3+ ultraviolet long afterglow driven in a photo-Fenton system

Abstract

Long afterglow photocatalysts have demonstrated the potential to support all-weather photocatalytic reactions. In this work, an Ag/Ca₂Al₂SiO₇:Pr³⁺ (Ag/CASO:Pr³⁺) composite was synthesized to enhance afterglow-driven photocatalytic activity. Ag loading introduced the surface plasmon resonance (SPR) effect, which increased light absorption capacity. It extended the afterglow duration and improved afterglow intensity by storing and releasing hot electrons. The Schottky junction between Ag and CASO:Pr³⁺ inhibited the recombination of photogenerated electrons and holes, increasing the active sites in photocatalytic reactions. The photodegradation performance of Ag/CASO:Pr³⁺ increased by up to 6.6-fold compared to CASO:Pr³⁺ under afterglow-driven conditions. The concentration of active species was further increased by adding Fe³⁺ and H₂O₂ to construct the Fenton system. Ag/CASO:Pr³⁺ achieved a 55% removal rate of TC and a 60% removal rate of NFX under its own afterglow-driven conditions within 1 h, following 10 min of ultraviolet light irradiation. This work expands the use of long afterglow luminescent materials and advances the development of all-weather photocatalytic technology.