Study on the Effect of A/B Site Co-Doping on the Oxygen Evolution Reaction Performance of Strontium Cobaltite

Abstract

The perovskite oxide SrCoO3−x is a promising oxygen electrocatalyst for renewable energy storage and conversion technologies. Here, A, B-site Co-doped perovskite Sr0.5Ba0.5Co0.95Mn0.05O3−x nanoparticles were rationally designed and synthesized by the sol-gel method with an average size of 30–40 nm. It has a remarkable intrinsical activity and stability in 1 M KOH solution. Compared with other A-site (SraA1−aCoO3−x A=Ba, Ca) and B-site doped perovskite (SrCobR1−bO3−x R=Mn, Fe, Ni, B) catalysts, Sr0.5Ba0.5Co0.95Mn0.05O3−x exhibits superior oxygen evolution reaction (OER) performance, smaller Tafel slope, and lower overpotential. The high electrochemical performance of Sr0.5Ba0.5Co0.95Mn0.05O3−x is attributed to its optimized crystal structure and the increase in the content of Co3+. This study demonstrates that highly symmetrical cubic perovskite structure catalytic displays better OER performance.

Keywords

• perovskite
• OER
• lattice oxygen
• electronic structure