Open AccessInfluence of Chemical Operation on the Electrocatalytic Activity of Ba0.5Sr0.5Co0.8Fe0.2O3−δ for the Oxygen Evolution Reaction
Author(s) -
Yuta Inoue,
Yuto Miyahara,
Kohei Miyazaki,
Yasuyuki Kondo,
Yuko Yokoyama,
Takeshi Abe
Publication year - 2022
Publication title -
journal of the electrochemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.258
H-Index - 271
eISSN - 1945-7111
pISSN - 0013-4651
DOI - 10.1149/1945-7111/ac4299
Subject(s) - oxygen evolution , electrochemistry , leaching (pedology) , electrolyte , electrocatalyst , chemistry , inorganic chemistry , chemical reaction , chemical state , water splitting , chemical engineering , electrode , catalysis , x ray photoelectron spectroscopy , biochemistry , environmental science , photocatalysis , soil science , engineering , soil water
Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3− δ (BSCF) is a promising electrocatalyst for the oxygen evolution reaction (OER) in alkaline solution. The OER activities of BSCF are gradually enhanced by prolonging the duration of electrochemical operation at OER potentials, but the underlying cause is not fully understood. In this study, we investigated the role of chemical operation, equivalent to immersion in alkaline solution, in the time-course of OER enhancement of BSCF. Interestingly, the time-course OER enhancement of BSCF was promoted not only by electrochemical operation, which corresponds to potential cycling in the OER region, but also by chemical operation. In situ Raman measurements clarified that chemical operation had a lower rate of surface amorphization than electrochemical operation. On the other hand, the leaching behavior of A-site cations was comparable between chemical and electrochemical operations. Since the OER activity of BSCF was stabilized by saturating the electrolyte with Ba 2+ , “chemical” A-site leaching was key to inducing the time-course OER enhancement on perovskite electrocatalysts. Based on these results, we provide a fundamental understanding of the role of chemical operation in the OER properties of perovskites.