Cation/anion-doping induced electronic structure modulation of CoMoO4 for enhanced hydrogen evolution

Abstract

The design and fabrication of high-performance, inexpensive and durable electrocatalyst toward hydrogen evolution reaction (HER) is supremely significant for alleviating energy crisis and environmental concerns, but still remaining challenging. Herein, we develop an experimental work based on etching and reduction strategy to reveal the remarkable effect of cation/anion co-doping in CoMoO4 on its intrinsic HER activity. The CoMoO4 with Fe and B incorporation (Fe/B-CoMoO4) exhibits a current density of 10 mA cm−2 with strikingly low potential of 38 mV coupling with Tafel slope of 51 mV dec-1, and manifesting a robust durability for 100 h with no attenuation, which is comparable to the state-of-the-art commercial Pt/C catalyst. The collective experimental and theoretical findings concomitantly illustrate that the enhanced performances are due to the strong synergistic effect resulting from the co-doping of Fe and B, which plays a pivotal role in finely tuning the electronic structure of CoMoO4, further optimizing the adsorption free energy of H intermediates and shifting the center of the d-band of Fe/B-CoMoO4 away from the Fermi level. This fantastic work highlights the critical role of foreign element incorporating for optimizing electronic structure of transition metal oxides toward HER, and offers valuable guiding principles for rational design of more efficient energy conversion devices.