Pt–Cu Interaction Induced Construction of Single Pt Sites for Synchronous Electron Capture and Transfer in Photocatalysis

Abstract Single‐atom photocatalysts have shown their fascinating strengths in enhancing charge transfer dynamics; however, rationally designing coordination sites by metal doping to stabilize isolated atoms is still challenging. Here, a one‐unit‐cell ZnIn 2 S 4 (ZIS) nanosheet with abundant Cu dopants serving as the suitable support to achieve a single atom Pt catalyst (Pt 1 /Cu–ZIS) is reported, and hence the metal single atom–metal dopant interaction at an atomic level is disclosed. Experimental results and density functional theory calculations highlight the unique stabilizing effect (Pt–Cu interaction) of single Pt atoms in Cu‐doped ZIS, while apparent Pt clusters are observed in pristine ZIS. Specifically, Pt–Cu interaction provides an extra coordination site except three S sites on the surface, which induces a higher diffusion barrier and makes the single atom more stable on the surface. Apart from stabilizing Pt single atoms, Pt–Cu interaction also serves as the efficient channel to transfer electrons from Cu trap states to Pt active sites, thereby enhancing the charge separation and transfer efficiency. Remarkably, the Pt 1 /Cu–ZIS exhibits a superb activity, giving a photocatalytic hydrogen evolution rate of 5.02 mmol g −1 h −1 , nearly 49 times higher than that of pristine ZIS.