Heteroatom-Doped Amorphous Cobalt-Molybdenum Oxides as a Promising Catalyst for Robust Hydrogen Evolution

Inorg Chem. 2022 Mar 28;61(12):5033-5039. doi: 10.1021/acs.inorgchem.1c03976. Epub 2022 Mar 11.

Abstract

The simultaneous manipulation of the catalytic activity and intrinsic electrical conductivity in a unified system is difficult yet meaningful to unravel the possible strategy that can enhance the hydrogen evolution reaction (HER) performance. Therefore, we propose a simple strategy to enhance the HER performance based on low-temperature redox reaction with ZIF-67@ZIF-8 as a sacrificial template to prepare zinc-doped amorphous CoMo8Ox (denoted as Zn/aCMO). Benefiting from the excellent compositional- and amorphous-based structural advantages of more exposure active sites, optimized electron transfer as well as a stable frame structure, the as-prepared electrode can drive hydrogen evolution at current densities of 10, 50, and 100 mA cm-2, which need ultralow overpotentials of 59, 138, and 189 mV, respectively, and the Tafel slope of the electrode was 66.2 mV dec-1 (1 M KOH). Meanwhile, the intrinsic activity of the prepared low-cost electrocatalyst was also determined, and the turnover frequency was up to 1.49 s-1 at an overpotential of 100 mV. In addition, after continuous testing for 160 h, there was a slight decay at the overpotential of 130 mV.