In situ/operando soft x-ray spectroscopic identification of a Co4+ intermediate in the oxygen evolution reaction of defective Co3O4 nanosheets
學年 111
學期 1
出版（發表）日期 2022-09-08
作品名稱 In situ/operando soft x-ray spectroscopic identification of a Co4+ intermediate in the oxygen evolution reaction of defective Co3O4 nanosheets
作品名稱（其他語言）
著者 Yu-Cheng Huang; Wei Chen; Zhaohui Xiao; Zhiwei Hu; Ying-Rui Lu; Jeng-Lung Chen; Chi-Liang Chen; Hong-Ji Lin; Chien-Te Chen; K. Thanigai Arul; Shuangyin Wang; Chung-Li Dong; Wu-Ching Chou
單位
出版者
著錄名稱、卷期、頁數 Journal of Physical Chemistry Letters 13(35), p.8386-8396
摘要 Defect engineering is an important means of improving the electrochemical performance of the Co3O4 electrocatalyst in the oxygen evolution reaction (OER). In this study, operando soft X-ray absorption spectroscopy (SXAS) is used to explore the electronic structure of Co3O4 under OER for the first time. The defect-rich Co3O4 (D-Co3O4) has a Co2.45+ state with Co2+ at both octahedral (Oh) and tetrahedral (Td) sites and Co3+ at Oh, whereas Co3O4 has Co2.6+ with Co2+ and Co3+ at Td and Oh sites, respectively. SXAS reveals that upon increasing the voltage, the Co2+ in D-Co3O4 is converted to low-spin Co3+, some of which is further converted to low-spin Co4+; most Co2+ in Co3O4 is converted to Co3+ but rarely to Co4+. When the voltage is switched off, Co4+ intermediates quickly disappear. These findings reveal Co(Oh) in D-Co3O4 can be rapidly converted to active low-spin Co4+ under operando conditions, which cannot be observed by ex situ XAS.
關鍵字
語言 en_US
ISSN 1948-7185
期刊性質 國外
收錄於 SCI
產學合作
通訊作者
審稿制度 是
國別 USA
公開徵稿
出版型式 ,電子版
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機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/124093 )