Modulating the Electroactivity of CuCoO for Hydrogen Evolution Assisted by Benzyl Alcohol Oxidation via the Morphological Structure.

The catalytic activity and morphological structure are closely related. Herein, the spinel structure CuCoO with different morphologies was constructed as the research model for the electrocatalytic benzyl alcohol (BA) oxidation and hydrogen evolution reaction (HER). By modulating the morphological structure, oxygen vacancy, and the high valence active centers, the octahedral CuCoO exhibited superior electrocatalytic activity and stability compared to other CuCoO samples with nanoplate/nanowire morphologies. Meanwhile, density functional theory calculations elucidated that octahedral CuCoO could significantly lower the reaction energy barriers of BA oxidation. Furthermore, the crystal orbital Hamilton population analysis was exploited to probe the intermediate adsorption/desorption on the vacancies. The morphology structure and vacancy effect contributed to the improved electrocatalytic performance. The present work demonstrated the important influence of the morphology structure and the accompanying electronic/vacancy effect on the catalytic activity experimentally and theoretically.