Multi-Phase Heterostructure of CoNiP/Cox P for Enhanced Hydrogen Evolution Under Alkaline and Seawater Conditions by Promoting H2 O Dissociation

Dong Liu; Haoqiang Ai; Mingpeng Chen; Pengfei Zhou; Bowen Li; Di Liu; Xinyu Du; Kin Ho Lo; Kar-Wei Ng; Shuang-Peng Wang; Shi Chen; Guichuan Xing; Jinsong Hu; Hui Pan

doi:10.1002/smll.202007557

Multi-Phase Heterostructure of CoNiP/Co_x P for Enhanced Hydrogen Evolution Under Alkaline and Seawater Conditions by Promoting H₂ O Dissociation

Small. 2021 Apr;17(17):e2007557. doi: 10.1002/smll.202007557. Epub 2021 Mar 18.

Authors

Dong Liu¹, Haoqiang Ai², Mingpeng Chen¹, Pengfei Zhou¹, Bowen Li¹, Di Liu¹, Xinyu Du², Kin Ho Lo², Kar-Wei Ng¹, Shuang-Peng Wang¹, Shi Chen¹, Guichuan Xing¹, Jinsong Hu³, Hui Pan^{1

4}

Affiliations

¹ Institute of Applied Physics and Materials Engineering, University of Macau, Macao, Macao SAR, 999078, China.
² Department of Electromechanical Engineering, Faculty of Science and Technology, University of Macau, Macao, Macao SAR, 999078, China.
³ CAS Key Laboratory of Molecular Nanostructure and Nanotechnology Institute of Chemistry, Chinese Academy of Sciences, 2 North first Street, Zhongguancun, Beijing, 100190, China.
⁴ Department of Physics and Chemistry, Faculty of Science and Technology, University of Macau, Macao, Macao SAR, 999078, China.

PMID: 33733600
DOI: 10.1002/smll.202007557

Abstract

Hydrogen evolution reaction (HER) is a key step for electrochemical energy conversion and storage. Developing well defined nanostructures as noble-metal-free electrocatalysts for HER is promising for the application of hydrogen technology. Herein, it is reported that 3D porous hierarchical CoNiP/Co_x P multi-phase heterostructure on Ni foam via an electrodeposition method followed by phosphorization exhibits ultra-highly catalytic activity for HER. The optimized CoNiP/Co_x P multi-phase heterostructure achieves an excellent HER performance with an ultralow overpotential of 36 mV at 10 mA cm^-2 , superior to commercial Pt/C. Importantly, the multi-phase heterostructure shows exceptional stability as confirmed by the long-term potential cycles (30,000 cycles) and extended electrocatalysis (up to 500 h) in alkaline solution and natural seawater. Experimental characterizations and DFT calculations demonstrate that the strong electronic interaction at the heterointerface of CoNiP/CoP is achieved via the electron transfer from CoNiP to the heterointerface, which directly promotes the dissociation of water at heterointerface and desorption of hydrogen on CoNiP. These findings may provide deep understanding on the HER mechanism of heterostructure electrocatalysts and guidance on the design of earth-abundant, cost-effective electrocatalysts with superior HER activity for practical applications.

Keywords: electrocatalysis; heterostructure; hydrogen generation; interface engineering; transition metal phosphide.