Cu₂S@Bi₂S₃ Double-Shelled Hollow Cages as a Nanocatalyst with Substantial Activity in Peroxymonosulfate Activation for Atrazine Degradation

Metal dichalcogenides are promising candidates for heterogeneous catalysis. Designing them as a double-shelled hollow nanostructure can enhance their performance owing to the high surface area provided by the hollow inner space. Herein, we demonstrate a multistage templating approach to prepare double-shelled cages with Bi2S3 nanoparticles as an outer shell and Cu2S as an inner shell. A facile deposition method, coupled with a benign sulfidation process, has been developed to prepare such a double-shelled hollow structure. The prepared Cu2S@Bi2S3 double-shelled cages demonstrated a substantial catalytic reactivity in peroxymonosulfate (PMS) activation for the degradation of atrazine in the dark. Such performance is attributed to the synergy between Cu2S and Bi2S3 in activating PMS, which promotes radical generation and enhances the catalytic performance. Our mechanistic studies revealed that hydroxyl radicals and singlet oxygen are the dominant species generated during atrazine degradation.