Trimetallic Molybdate Nanobelts as Active and Stable Electrocatalysts for the Oxygen Evolution Reaction

The research on high-efficiency oxygen evolution reaction (OER) electrocatalysts based on non-precious-metal materials is extremely urgent for water dissociation but still challenging. Herein, a unique class of molybdate nanobelts (NBs) with high surface area, fast electron transportation, and fast diffusion of electrolyte were constructed for enhanced OER via electronic engineering. We discovered that introducing a third metal modifies the electronic environment of molybdate NBs, leading to favorable intermediate adsorption on the catalysts. The optimized Mo51Ni40Fe9 NBs exhibit an overpotential of 257 mV to obtain 10 mA cm(-2) and a Tafel slope of 51 mV dec(-1). By combination with commercial Pt/C as the cathodic catalyst, the water electrolyzer only requires a potential of 1.55 V to achieve 10 mA cm(-2) and exhibits superior stability with small current density decay after 18 h. On the basis of X-ray photoelectron spectroscopy and surface valence band spectra, the enhanced OER performance is tightly connected with the appropriate binding energy between reactive intermediates and active sites. This work proposes an open avenue of electronic engineering strategy for the design of efficient electrocatalysts.