Versatile Synthesis of Hollow Metal Sulfides via Reverse Cation Exchange Reactions for Photocatalytic CO2 Reduction

Abstract Herein, we explore a general Cu 2− x S nanocube template‐assisted and reverse cation exchange‐mediated growth strategy for fabricating hollow multinary metal sulfide. Unlike the traditional cation exchange method controlled by the metal sulfide constant, the introduction of tri‐n‐butylphosphine (TBP) can reverse cation exchange to give a series of hollow metal sulfides. A variety of hollow multinary metal sulfide cubic nanostructures has been demonstrated while preserving anisotropic shapes to the as‐synthesized templates, including binary compounds (CdS, ZnS, Ag 2 S, PbS, SnS), ternary compound (CuInS 2 , Zn x Cd 1− x S), and quaternary compound (single‐atom platinum anchored Zn x Cd 1− x S; Zn x Cd 1− x S‐Pt 1 ). Experimental and density functional theory (DFT) calculations show that the hollow metal sulfide semiconductors obtained could significantly improve the separation and migration of photogenerated electron‐hole pairs. Owing to the efficient charge transfer, the Zn x Cd 1− x S‐Pt 1 exhibited outstanding photocatalytic performance of CO 2 to CO, with the highest CO generation rate of 75.31 μmol h −1 .