Enhanced cycling stability of La0.2Sr0.8CoO3−δ for oxygen evolution reaction via trace doping of Nb. Issue 24 (15th December 2022)

• Record Type: Journal Article
• Authors: Zhang, Chi; Cui, Yu; Ke, Wenxue; Liang, Yi; Chao, Yang; Han, Ning; Liang, Ping; He, Xin
• Is Part Of: Ceramics international. Volume 48:Issue 24(2022)
• Page Start: 36992
• Page End: 36999
• Publication Date: 2022-12-15
• Subjects: Perovskite oxides -- Nb dopant -- Oxygen evolution reaction -- Stability; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2022.08.269
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Perovskite oxides (ABO3−δ ) have highly tuneable compositions because of the abundance of element candidates for the A-, B-, and O-sites. Generally, perovskite catalytic activity for the oxygen evolution reaction (OER) can be improved by B-site doping. However, doping does not always enhance activity. This work shows that Nb doping of La0.2 Sr0.8 CoO3−δ (LSC) is detrimental to OER activity but benefits cycling stability. With 10 at.% Nb doping (La0.2 Sr0.8 Co0.9 Nb0.1 O3−δ, LSCN10), the overpotential at 10 mA cm −2 increased to 450 mV, 30 mV higher than that of the undoped LSC. Accelerated stability testing demonstrated enhanced stability with only 5 mV attenuation after 1000 cycles. Density functional theory (DFT) revealed that the high stability stems from the downward shift of the O 2 p band centre relative to the Fermi level. The findings of this work provide guidance for the design of highly stable OER perovskite catalysts.