Accelerated alkaline hydrogen evolution on M(OH) x /M-MoPO x (M = Ni, Co, Fe, Mn) electrocatalysts by coupling water dissociation and hydrogen ad-desorption steps

Lishan Peng; Mansheng Liao; Xingqun Zheng; Yao Nie; Ling Zhang; Minjie Wang; Rui Xiang; Jian Wang; Li Li; Zidong Wei

doi:10.1039/c9sc04603h

Accelerated alkaline hydrogen evolution on M(OH) _x /M-MoPO _x (M = Ni, Co, Fe, Mn) electrocatalysts by coupling water dissociation and hydrogen ad-desorption steps

Chem Sci. 2020 Jan 27;11(9):2487-2493. doi: 10.1039/c9sc04603h.

Authors

Lishan Peng¹, Mansheng Liao¹, Xingqun Zheng¹, Yao Nie², Ling Zhang¹, Minjie Wang¹, Rui Xiang¹, Jian Wang¹, Li Li¹, Zidong Wei¹

Affiliations

¹ The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, School of Chemistry and Chemical Engineering, Chongqing University Chongqing 400044 China zdwei@cqu.edu.cn liliracial@cqu.edu.cn.
² College of Chemistry, Chongqing Normal University Chongqing 400047 China.

Abstract

Developing efficient and cheap electrocatalysts for the alkaline hydrogen evolution reaction is still a big challenge due to the sluggish water dissociation kinetics as well as poor M-H_ad energetics. Herein, hydroxide modification and element incorporation have been demonstrated to realize a synergistic modulation on a new class of M(OH) _x /M-MoPO _x catalysts for accelerating water dissociation and hydrogen ad-desorption steps in the HER. Theoretical and experimental results disclosed that in situ modification with hydroxide endowed M(OH) _x /M-MoPO _x with a strong ability to dissociate water, and meanwhile, oxygen incorporation effectively optimized the M-H_ad energetics of the NiMoP catalyst. Moreover, the interaction between M(OH) _x and M-MoPO _x components in M(OH) _x /M-MoPO _x further enhances their ability to catalyze the two elementary steps in alkaline hydrogen evolution, providing a wide avenue for efficiently catalyzing hydrogen evolution. In general, the optimized Ni(OH)₂/NiMoPO _x catalyst exhibits excellent alkaline HER activity and durability, superior to the state-of-the-art Pt/C catalyst when the overpotential exceeds 65 mV.