Surface Electronic Modulation with Hetero-Single Atoms to Enhance Oxygen Evolution Catalysis.

Oxygen evolution catalysis plays a crucial role in the solar-to-fuel conversion for green energy applications. However, developing efficient and stable catalysts for the oxygen evolution catalysis remains a great challenge. Here, we successfully activate an inefficient oxygen evolution catalyst using a simple single atom tailoring strategy. The Rh element with its unfilled 4d8 electron configuration was selected to atomically implant into a Cu oxide matrix, which has a filled 3d10 electron configuration. The hetero-Rh single atom (SA) migration was achieved by dispersing Cu2O nanocubes in a RhCl3 aqueous solution, enabling an ion exchange process. The activated catalyst (Cu2O-RhSA) exhibited significantly enhanced catalytic activity toward oxygen evolution in alkaline media, surpassing the performance of pristine Cu2O nanocubes and commercial IrO2. A theoretical study further confirmed that the migrated hetero-Rh SAs can tailor the interaction between the Cu and O sites, modulating the electron density distribution on the surface of Cu2O, leading to a more favorable oxygen evolution process.