Modulating Surface Chemical States of SnS₂ Nanosheets Via Zn Doping for Efficient Photoelectrochemical Water Splitting

Here, a gentle cation-exchange-mediated approach is employed to immobilize Zn cations on the surface of SnS2 nanosheets for the Zn-SnS2 photoanode construction. Benefit from the redistribution of surface charges induced by the Zn–S configuration, the Zn-SnS2 photoanode catalyst possesses excellent separation ability of photogenerated electrons and holes. Therefore, the optimized Zn-SnS2 photoanode exhibits exceptional Photoelectrochemical (PEC) water splitting performance, achieving a photocurrent density of 1.28 mA·cm–2 at 1.23 VRHE with outstanding long-term stability, which is 4.13 times greater than that of SnS2 (0.31 mA·cm–2). Theoretical simulation calculation reveals that the introduction of Zn enhances adsorption of water molecules and intermediates, reduces the reaction energy barrier, and accelerates the kinetics of the PEC water oxidation reaction. This research offers a viable strategy to enhance photo electrocatalytic efficacy via Zn ion incorporation.