【摘 要】
：
Perovskites (Ba0.5Sr0.5)1-xCo0.8Fe0.2O3-δ (x =0.02,0.05,0.1 denoted as BSCF-0.98,BSCF-0.95,BSCF-0.9,respectively) with A-site cation defects are synthesized by sirnple and efficient sol-gel method and are proved to have better OER catalytic effect than th
【机 构】
：
Department of Chemistry,University of Science and Technology of China,Hefei,Anhui 230026,China;CAS K
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Perovskites (Ba0.5Sr0.5)1-xCo0.8Fe0.2O3-δ (x =0.02,0.05,0.1 denoted as BSCF-0.98,BSCF-0.95,BSCF-0.9,respectively) with A-site cation defects are synthesized by sirnple and efficient sol-gel method and are proved to have better OER catalytic effect than the well-known Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF) oxides.BSCF-0.95 exhibits the best OER catalytic activity in the series perovskite.The current density of BSCF-0.95 is about 56％ higher than that of BSCF oxide at a potential of 1.7 V.The experimental studies have shown that compared with BSCF,BSCF-0.95 oxide has a larger electrochemical surface area (ECSA),a higher content of O22-species related to surface oxy-gen vacancies,and faster charge transfer rate,which may be the factors for the enhancement of OER activity.The theoretical calcula-tion results prove that the center positions of the O 2p-band of perovskite with A-site cation defects are closer to the Fermi level than BSCF oxide,which agrees with the OER performance trend of the material.
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