Multielement-Doped LaFeO3 Perovskites Synthesized by Supercritical-Water-Flow Synthesis for Oxygen Evolution Reaction

Abstract

LaFeO3-based perovskite oxides are known oxygen evolution reaction (OER) electrocatalysts. However, systematic investigations of multielement doping remain limited, and catalyst reconstruction complicates interpretation of catalytic behavior. Herein, continuous supercritical-water-flow synthesis was used to produce a compositionally diverse LaFeO3-based series with distinct OER activities, revealing nonlinear effects of multielement substitution. All catalysts underwent substantial reconstruction during OER. Despite this, activity did not consistently correlate with crystalline reconstruction products, suggesting contributions from poorly crystalline or amorphous-like states. These results indicate that the perovskites may act as compositionally tunable precatalysts, with post-OER composition possibly contributing to the observed activity differences.