Affordable Access

deepdyve-link
Publisher Website

Steering elementary steps towards efficient alkaline hydrogen evolution via size-dependent Ni/NiO nanoscale heterosurfaces

Authors
  • Zhao, Lu1, 2
  • Zhang, Yun1, 3
  • Zhao, Zhonglong4
  • Zhang, Qing-Hua5
  • Huang, Lin-Bo1, 2
  • Gu, Lin5
  • Lu, Gang4
  • Hu, Jin-Song1, 2
  • Wan, Li-Jun1, 2
  • 1 Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, China , (China)
  • 2 University of Chinese Academy of Sciences, China , (China)
  • 3 College of Chemistry and Materials Science, Sichuan Normal University, China , (China)
  • 4 Department of Physics and Astronomy, California State University Northridge, USA , (United States)
  • 5 Beijing National Research Center for Condensed Matter Physics, Collaborative Innovation Center of Quantum Matter, Institute of Physics, Chinese Academy of Sciences, China , (China)
Type
Published Article
Journal
National Science Review
Publisher
Oxford University Press
Publication Date
Oct 01, 2019
Volume
7
Issue
1
Pages
27–36
Identifiers
DOI: 10.1093/nsr/nwz145
PMID: 34692014
PMCID: PMC8288842
Source
PubMed Central
Keywords
Disciplines
  • Research Article
  • Chemistry
License
Unknown

Abstract

Alkaline hydrogen evolution reaction (HER), consisting of Volmer and Heyrovsky/Tafel steps, requires extra energy for water dissociation, leading to more sluggish kinetics than acidic HER. Despite the advances in electrocatalysts, how to combine active sites to synergistically promote both steps and understand the underlying mechanism remain largely unexplored. Here, Density Functional Theory (DFT) calculations predict that NiO accelerates the Volmer step while metallic Ni facilitates the Heyrovsky/Tafel step. A facile strategy is thus developed to control Ni/NiO heterosurfaces in uniform and well-dispersed Ni-based nanocrystals, targeting both reaction steps synergistically. By systematically modulating the surface composition, we find that steering the elementary steps through tuning the Ni/NiO ratio can significantly enhance alkaline HER activity, and Ni/NiO nanocrystals with a Ni/NiO ratio of 23.7% deliver the best activity, outperforming other state-of-the-art analogues. The results suggest that integrating bicomponent active sites for elementary steps is effective for promoting alkaline HER, but they have to be balanced.

Report this publication

Statistics

Seen <100 times