Enhancing Bifunctional Electrocatalytic Activities via Metal d-Band Center Lift Induced by Oxygen Vacancy on the Subsurface of Perovskites
Cited 0 times inCited 0 times in
- Enhancing Bifunctional Electrocatalytic Activities via Metal d-Band Center Lift Induced by Oxygen Vacancy on the Subsurface of Perovskites
- Lee, Hansol; Gwon, Ohhun; Choi, Keunsu; Zhang, Linjuan; Zhou, Jing; Park, Jungmin; Yoo, Jung-Woo; Wang, Jian-Qiang; Lee, Jun Hee; Kim, Guntae
- Issue Date
- AMER CHEMICAL SOC
- ACS CATALYSIS, v.10, no.8, pp.4664 - 4670
- For efficient electrochemical catalysts, several molecular-scale descriptors have been proposed for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Various descriptors of perovskite catalysts have been proposed successfully for understanding either ORR or OER, but previous studies are insufficient to explain and thus boost up both ORR and OER simultaneously due to obstacles such as many different chemical compositions, structures, and metal orbital bands. Therefore, we investigate ORR/OER activities as a function of only oxygen vacancy concentration in perovskite oxides of Sm0.5Sr0.5CoO3-delta (SSC) to check the close relationship between delta (delta) and the electronic structure. Interestingly, the improved performance of both ORR and OER is explained by the change in the oxidation state of the transition metal caused by the increase in oxygen vacancies. Unfortunately, most previous research studies have focused on the effect of only oxygen vacancy (delta) on responsiveness. To confirm this, we performed density functional theory (DFT) analysis to find the more dominant factor on whether the activity descriptor is either delta or oxidation states of transition metals. The DFT analysis reveals that the ORR and OER activities of SSC are simultaneously improved by the reduced gap between d- and p-band centers (Delta Ed-p) caused by the raised d-band center (M-d). X-ray absorption spectroscopy has provided the exact electronic states of all the transition metals. Here, we report that an important factor of ORR/OER is affected only by the oxidation state of the transition metal in the perovskite oxide, not by the oxygen vacancy concentration.
- Appears in Collections:
- MSE_Journal Papers
- Files in This Item:
- There are no files associated with this item.
can give you direct access to the published full text of this article. (UNISTARs only)
Show full item record
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.