Phase-Segregated SrCo0.8Fe0.5- xO3-δ/Fe x O y Heterostructured Catalyst Promotes Alkaline Oxygen Evolution Reaction

Yunan Yi; Qianbao Wu; Junshan Li; Weitang Yao; Chunhua Cui

doi:10.1021/acsami.0c22355

Phase-Segregated SrCo_0.8Fe_{0.5- x}O_3-δ/Fe _x O _y Heterostructured Catalyst Promotes Alkaline Oxygen Evolution Reaction

ACS Appl Mater Interfaces. 2021 Apr 21;13(15):17439-17449. doi: 10.1021/acsami.0c22355. Epub 2021 Apr 8.

Authors

Yunan Yi¹, Qianbao Wu¹, Junshan Li¹, Weitang Yao², Chunhua Cui¹

Affiliations

¹ Molecular Electrochemistry Laboratory, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, China.
² School of Mechanical Engineering, Chengdu University, Chengdu 610106, China.

PMID: 33829757
DOI: 10.1021/acsami.0c22355

Abstract

Perovskite oxide is a promising alternative to noble metal electrocatalysts for the oxygen evolution reaction (OER). However, as one of the most active oxide catalysts, cubic SrCoO₃ presents poor OER performance relative to the theoretically predicted activity. Appropriate introduction of a guest component in the lattice and surface could largely promote the OER activity. Herein, we present a thermal-induced phase-segregation strategy to synthesize a heterostructured SrCo_0.8Fe_0.5-xO_3-δ/Fe_xO_y (SC8F5) catalyst for OER. This novel perovskite/Fe₃O₄ heterostructure allows us to enhance the electrical conductivity ability, increase the Co oxidation state, and activate the surface oxygen to active oxygen species (O₂^2-/O^-) for efficient OER. In contrast to the poor stability of SrCo_0.8Fe_0.2O_3-δ, we found that the SC8F5 heterostructure with segregated Fe₃O₄ on the surface can mitigate surface reconstruction and stabilize the catalyst structure, thereby increasing catalytic stability.

Keywords: heterostructures; oxygen evolution reaction; perovskite oxides; phase separation; surface reconstruction.