Ultrafine Ag Nanoparticles Anchored on Hollow S-Doped CeO2 Spheres for Synergistically Enhanced Tetracycline Degradation under Visible Light

Photocatalytic degradation of organic contaminants is thought to be a potential means for resolving the growing challenge of environmental pollution. However, the efficacy is severely constrained by ineffective light harvesting and slow charge separation. Herein, ultrafine Ag nanoparticles immobilized in sulfur-doped hollow CeO2 spheres (denoted Ag/CeO2–xSx) were synthesized through self-assembly and a subsequent heat-treatment strategy. Obtained Ag/CeO2–xSx shows promoted utilization efficiency of light, remarkably improved photogenerated carrier separation efficiency, and enlarged surface area. Coupling the synergetic enhancement of light harvesting and charge separation, optimized Ag/CeO2–xSx exhibits superb photocatalytic tetracycline degradation activity (94.2%, 60 min) under visible light irradiation, and its corresponding rate constant (0.0397 min–1) was nearly 28.4-fold higher than that of commercial CeO2 (0.0014 min–1). This analysis provides a simple method for building high-efficiency photocatalysts for solar light-driven wastewater treatment.