Manipulation on active electronic states of metastable phase β-NiMoO4 for large current density hydrogen evolution

Zengyao Wang; Jiyi Chen; Erhong Song; Ning Wang; Juncai Dong; Xiang Zhang; Pulickel M Ajayan; Wei Yao; Chenfeng Wang; Jianjun Liu; Jianfeng Shen; Mingxin Ye

doi:10.1038/s41467-021-26256-1

Manipulation on active electronic states of metastable phase β-NiMoO₄ for large current density hydrogen evolution

Nat Commun. 2021 Oct 13;12(1):5960. doi: 10.1038/s41467-021-26256-1.

Authors

Zengyao Wang^#^{1

2}, Jiyi Chen^#^{1

3

4}, Erhong Song^#⁵, Ning Wang⁶, Juncai Dong⁷, Xiang Zhang⁸, Pulickel M Ajayan⁸, Wei Yao¹, Chenfeng Wang¹, Jianjun Liu⁹, Jianfeng Shen¹⁰, Mingxin Ye¹¹

Affiliations

¹ Institute of Special Materials and Technology, Fudan University, Shanghai, China.
² Department of Chemistry, Fudan University, Shanghai, China.
³ Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Binhai New City, Fuzhou, China.
⁴ Department of Chemical and Biomolecular Engineering, National University of Singapore, Southeast Asia, Singapore.
⁵ State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China.
⁶ Institute of Environment and Life, Beijing University of Technology, Beijing, PR China.
⁷ Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Science, Beijing, China.
⁸ Department of Materials Science and Nano Engineering, Rice University, Houston, USA.
⁹ State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China. jliu@mail.sic.ac.cn.
¹⁰ Institute of Special Materials and Technology, Fudan University, Shanghai, China. jfshen@fudan.edu.cn.
¹¹ Institute of Special Materials and Technology, Fudan University, Shanghai, China. mxye@fudan.edu.cn.

^# Contributed equally.

Abstract

Non-noble transition metal oxides are abundant in nature. However, they are widely regarded as catalytically inert for hydrogen evolution reaction (HER) due to their scarce active electronic states near the Fermi-level. How to largely improve the HER activity of these kinds of materials remains a great challenge. Herein, as a proof-of-concept, we design a non-solvent strategy to achieve phosphate substitution and the subsequent crystal phase stabilization of metastable β-NiMoO₄. Phosphate substitution is proved to be imperative for the stabilization and activation of β-NiMoO₄, which can efficiently generate the active electronic states and promote the intrinsic HER activity. As a result, phosphate substituted β-NiMoO₄ exhibits the optimal hydrogen adsorption free energy (-0.046 eV) and ultralow overpotential of -23 mV at 10 mA cm^-2 in 1 M KOH for HER. Especially, it maintains long-term stability for 200 h at the large current density of 1000 mA cm^-2 with an overpotential of only -210 mV. This work provides a route for activating transition metal oxides for HER by stabilizing the metastable phase with abundant active electronic states.