タイトル |
-
en
Highly Durable Oxygen Evolution Reaction Catalyst: Amorphous Oxyhydroxide Derived from Brownmillerite-Type Ca2FeCoO5
|
作成者 |
|
アクセス権 |
open access |
権利情報 |
-
en
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.0c00159.
|
主題 |
-
Other
en
OER
-
Other
en
brownmillerite
-
Other
en
Ca2FeCoO5
-
Other
en
electrocatalyst
-
Other
en
auger electron spectroscopy
-
Other
en
extended X-ray absorption fine structure
|
内容注記 |
-
Abstract
en
Brownmillerite-type Ca2FeCoO5 (CFCO) is a highly active electrocatalyst for the oxygen evolution reaction (OER). In this study, we identified the actual catalytically active phase of this oxide formed via the long-term OER and, moreover, demonstrated that the active phase can persist during the OER for 4 weeks without significant loss of electrocatalytic activity. The long-term durability tests were carried out on CFCO via continuous galvanostatic OER in 4 mol dm(-3) KOH aqueous solution for periods ranging from a few hours to 1 month, and the specimens submitted to the tests were characterized by means of electrochemical measurements and structural analysis using scanning electron microscopy, X-ray diffraction, transmission electron microscopy, Auger electron spectroscopy, and X-ray absorption fluorescence spectroscopy. CFCO was readily converted to amorphous cobalt oxyhydroxides with 10% Fe substituents through the OER process, and these compounds had a local rearrangement similar to that of the layered gamma-CoOOH-type structure. This transformation involved large morphological changes of the oxide particles because of the extensive dissolution of Ca and Fe, yielding skeletal grains made of oxyhydroxide nanosheet aggregates. The extended durability studies with total polarization charge density of the order of 10(5) C cm(-2) revealed that a (Co, Fe)OOH-like compound is the actual electrocatalytic phase.
|
出版者 |
en
American Chemical Society
|
日付 |
|
言語 |
|
資源タイプ |
journal article |
出版タイプ |
AM |
資源識別子 |
HDL
http://hdl.handle.net/2115/81967
|
関連 |
-
isVersionOf
DOI
https://doi.org/10.1021/acsaem.0c00159
|
収録誌情報 |
-
-
en
ACS applied energy materials
-
巻3
号6
開始ページ5269
終了ページ5276
|
ファイル |
|
コンテンツ更新日時 |
2023-07-26 |