Perovskite-type oxides hold promise as supports for Ir-based acidic oxygen evolution reaction (OER) catalysts, yet their instability under harsh conditions limits practical application. Defect engineering of IrOx-perovskite heterostructures offers new opportunities for acidic oxygen evolution catalysis. Here, we demonstrate thermal-reconstructed oxygen defect regulation in IrOx@La1.2Sr0.8Ni0.6Fe0.4O4+δ (IrOx@LSNF) catalysts, where controlled calcination induces in situ growth of oxygen-deficient amorphous IrOx on Ruddlesden-Popper perovskite. Thermal reconstruction at 250°C generates oxygen-defect-rich amorphous IrOx on LSNF (IrOx@LSNF-250), creating strong metal-metal oxides support interaction (MMSI) that enhances active-site utilization while favoring the lattice oxygen participation mechanism (LOM) for superior OER activity. Remarkably, the perovskite-anchored IrOx heterostructure maintains considerable durability in half-cell acidic media against LOM-induced collapse, demonstrating how defect-engineered thermal reconstruction simultaneously addresses activity-stability trade-offs in acidic OER catalysis. The optimized OER performance of IrOx@LSNF-250 in acidic media are attributed to perovskite-anchored Ir species suppressing dissolution, together with thermal-reconstruction-enriched oxygen defects optimizing LOM. This work establishes a paradigm for defect-engineered heterostructures via thermal reconstruction, advancing perovskite-based OER catalysts beyond conventional stability-activity trade-offs in acidic media.
Cheng et al. (Fri,) studied this question.