Spinel Co3O4, comprising one Co2+ in the tetrahedral site (Co2+Td) and the other two Co3+ in the octahedral site (Co3+Oh), has been widely explored as promising oxygen evoltuion reaction (OER) catalyst. Here, we investigated the geometrical-site-dependent OER activity of Co3O4 catalyst by substituting Co2+Td and Co3+Oh with inactive Zn2+ and Al3+, respectively. Following a thorough in-operando analysis by electrochemical impedance spectroscopy and X-ray absorption spectroscopy, it is revealed that Co2+Td site is responsible for the formation of cobalt oxyhydroxide (CoOOH), which acts as the active site for water oxidation.

In-operando identification of geometrical-site-dependent water oxidation activity of spinel Co3O4

251st National Meeting (2016)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.