open access

https://hdl.handle.net/2115/83735

In Situ Activation of Anodized Ni-Fe Alloys for the Oxygen Evolution Reaction in Alkaline Media

英語

porous anodic film

2020-12-28

American Chemical Society

ACS applied energy materials

3(12)

12316-12326

A simple anodizing technique has been employed to develop highly active electrocatalysts that can be applied to the oxygen evolution reaction (OER) in alkaline media. NiFe alloys were electrodeposited and anodized to form a porous electrocatalytic layer. This approach produces highly active electrodes without the need for noble metals, binders, or conductive carbon additives. The as-anodized electrode initially exhibits poor OER activity in 1.0 mol dm(-3) KOH; however, the effects of potential cycling improve the OER activity to an extent that an overpotential as low as 0.26 V at 10 mA cm(-2) is observed for the anodized Ni-11.8 at. % Fe electrode. Although significant in situ activation is achieved with anodized NiFe electrodes, this activation is less significant for as-deposited NiFe or anodized Ni electrodes. Furthermore, OER activity is observed to be composition-dependent, with the Ni-11.8 at. % Fe electrode exhibiting the greatest activity. A porous fluoride-rich, Fe-doped Ni oxyfluoride layer produced by anodizing is converted via potential cycling to an amorphous or poorly crystalline Fe-doped Ni(OH)(2) layer with a nanoflake-like morphology. The high activity is maintained even after the removal of most of the fluoride. Thus, the F-rich, Fe-doped Ni oxyfluoride is a promising precursor to develop a highly active OER electrode.

学術雑誌論文

Accepted Manuscript

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS applied energy materials, copyright c American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsaem.0c02362, see http://pubs.acs.org/page/policy/articlesonrequest/index.html.

2574-0962