Systematic study of oxygen evolution activity and stability on La1-xSrxFeO3-δ perovskite electrocatalysts in alkaline media

Sixuan She, Jie Yu, Wanqi Tang, Yinlong Zhu, Yubo Chen, Jaka Sunarso, Wei Zhou, Zongping Shao

Research output: Contribution to journalArticleResearchpeer-review

79 Citations (Scopus)

Abstract

Perovskite oxide is an attractive low-cost alternative catalyst for oxygen evolution reaction (OER) relative to the precious metal oxide-based electrocatalysts (IrO2 and RuO2). In this work, a series of Sr-doped La-based perovskite oxide catalysts with compositions of La1-xSrxFeO3-δ (x = 0, 0.2, 0.5, 0.8, and 1) are synthesized and characterized. The OER-specific activities in alkaline solution increase in the order of LaFeO3-δ (LF), La0.8Sr0.2FeO3-δ (LSF-0.2), La0.5Sr0.5FeO3-δ (LSF-0.5), SrFeO3-δ (SF), and La0.2Sr0.8FeO3-δ (LSF-0.8). We establish a direct correlation between the enhancement in the specific activity and the amount of surface oxygen vacancies as well as the surface Fe oxidation states. The improved specific activity for LSF-0.8 is clearly linked to the optimum amount of surface oxygen vacancies and surface Fe oxidation states. We also find that the OER performance stability is a function of the crystal structure and the deviation in the surface La and/or Sr composition(s) from their bulk stoichiometric compositions. The cubic structure and lower deviation, as is the case for LSF-0.8, led to a higher OER performance stability. These surface performance relations provide a promising guideline for constructing efficient water oxidation.

Original languageEnglish
Pages (from-to)11715-11721
Number of pages7
JournalACS Applied Materials & Interfaces
Volume10
Issue number14
DOIs
Publication statusPublished - 11 Apr 2018
Externally publishedYes

Keywords

  • LaSrxFeO
  • oxygen evolution reaction
  • structure
  • surface Fe oxidation states
  • surface oxygen vacancies

Cite this