Metallic S-CoTe with Surface Reconstruction Activated by Electrochemical Oxidation for Oxygen Evolution Catalysis

Developing highly active electrocatalysts toward oxygen evolution reaction (OER) is critical for the application of water splitting for hydrogen production and can further alleviate the energy crisis problem, but still remaining challenging. Especially, unlocking the catalytic site, in turn, helps design the available catalysts. Herein, the nanorod cobalt telluride with sulfur incorporation grown on a carbon cloth (S-CoTe/CC) as catalysts for OER, which displays extraordinary catalytic activity, is reported. Significantly, the in situ formed CoOOH species on the surface of S-CoTe merited from the structure evolution during the OER process serves as the active species. Furthermore, density functional theory calculations demonstrate that sulfur incorporation can tailor the electronic structure of active species and substantially optimize the free energy, accelerating the OER kinetics. This work provides an in-depth understanding of enhanced OER mechanism through foreign elements incorporating into precatalysts and is beneficial for the guiding design of more efficient catalysts.