Skip to main content
eScholarship
Open Access Publications from the University of California

Identification of highly active Fe sites in (Ni,Fe)OOH for electrocatalytic water splitting.

  • Author(s): Friebel, Daniel
  • Louie, Mary W
  • Bajdich, Michal
  • Sanwald, Kai E
  • Cai, Yun
  • Wise, Anna M
  • Cheng, Mu-Jeng
  • Sokaras, Dimosthenis
  • Weng, Tsu-Chien
  • Alonso-Mori, Roberto
  • Davis, Ryan C
  • Bargar, John R
  • Nørskov, Jens K
  • Nilsson, Anders
  • Bell, Alexis T
  • et al.

Published Web Location

https://doi.org/10.1021/ja511559d
Abstract

Highly active catalysts for the oxygen evolution reaction (OER) are required for the development of photoelectrochemical devices that generate hydrogen efficiently from water using solar energy. Here, we identify the origin of a 500-fold OER activity enhancement that can be achieved with mixed (Ni,Fe)oxyhydroxides (Ni(1-x)Fe(x)OOH) over their pure Ni and Fe parent compounds, resulting in one of the most active currently known OER catalysts in alkaline electrolyte. Operando X-ray absorption spectroscopy (XAS) using high energy resolution fluorescence detection (HERFD) reveals that Fe(3+) in Ni(1-x)Fe(x)OOH occupies octahedral sites with unusually short Fe-O bond distances, induced by edge-sharing with surrounding [NiO6] octahedra. Using computational methods, we establish that this structural motif results in near optimal adsorption energies of OER intermediates and low overpotentials at Fe sites. By contrast, Ni sites in Ni(1-x)Fe(x)OOH are not active sites for the oxidation of water.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Main Content
Current View