Operando identification of the dynamic behavior of oxygen vacancy-rich Co3O4 for oxygen evolution reaction

doi:10.1021/jacs.0c00257

淡江大學機構典藏 > 工學院 > 電機工程學系暨研究所 > 期刊論文 > Item 987654321/120730

請使用永久網址來引用或連結此文件: https://tkuir.lib.tku.edu.tw/dspace/handle/987654321/120730

題名:	Operando identification of the dynamic behavior of oxygen vacancy-rich Co3O4 for oxygen evolution reaction
作者:	Xiao, Z.;Huang, Y. C.;Dong, C. L.;Xie, C.;Liu, Z.;Du, S.;Chen, W.;Yan, D.;Tao, L.;Shu, Z.;Zhang, G.;Duan, H.;Wang, Y.;Zou, Y.;Chen, R.;Wang, S.
日期:	2020-06-14
上傳時間:	2021-05-05 12:12:23 (UTC+8)
摘要:	The exact role of a defect structure on transition metal compounds for electrocatalytic oxygen evolution reaction (OER), which is a very dynamic process, remains unclear. Studying the structure–activity relationship of defective electrocatalysts under operando conditions is crucial for understanding their intrinsic reaction mechanism and dynamic behavior of defect sites. Co3O4 with rich oxygen vacancy (VO) has been reported to efficiently catalyze OER. Herein, we constructed pure spinel Co3O4 and VO-rich Co3O4 as catalyst models to study the defect mechanism and investigate the dynamic behavior of defect sites during the electrocatalytic OER process by various operando characterizations. Operando electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) implied that the VO could facilitate the pre-oxidation of the low-valence Co (Co2+, part of which was induced by the VO to balance the charge) at a relatively lower applied potential. This observation confirmed that the VO could initialize the surface reconstruction of VO–Co3O4 prior to the occurrence of the OER process. The quasi-operando X-ray photoelectron spectroscopy (XPS) and operando X-ray absorption fine structure (XAFS) results further demonstrated the oxygen vacancies were filled with OH• first for VO–Co3O4 and facilitated pre-oxidation of low-valence Co and promoted reconstruction/deprotonation of intermediate Co–OOH•. This work provides insight into the defect mechanism in Co3O4 for OER in a dynamic way by observing the surface dynamic evolution process of defective electrocatalysts and identifying the real active sites during the electrocatalysis process. The current finding would motivate the community to focus more on the dynamic behavior of defect electrocatalysts.
關聯:	JACS 142(28), 12087-12095
DOI:	10.1021/jacs.0c00257
顯示於類別:	[電機工程學系暨研究所] 期刊論文

文件中的檔案:

檔案	描述	大小	格式	瀏覽次數
index.html		0Kb	HTML	59	檢視/開啟
Operando identification of the dynamic behavior of oxygen vacancy-rich Co3O4 for oxygen evolution reaction.pdf		1396Kb	Adobe PDF	3	檢視/開啟

在機構典藏中所有的資料項目都受到原著作權保護.

TAIR相關文章

資料載入中.....