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  • Mechanistic insights into oxygen reduction reaction on metal/perovskite catalysts: Interfacial interactions and reaction pathways
Title: Mechanistic insights into oxygen reduction reaction on metal/perovskite catalysts: Interfacial interactions and reaction pathways
The oxygen reduction reaction (ORR) is a critical process in energy conversion systems, influencing the efficiency and performance of various devices such as fuel cells, batteries, and electrolyzers. Perovskite-supported metal materials (metal/perovskite) offer several advantages as ORR electrocatalysts, including strong metal-support interactions, oxygen vacancy formation in the perovskite lattice, and synergistic triple-phase boundary (TPB) activity at the interface. Despite their significance, the mechanistic understanding of ORR on metal/perovskite catalysts remains incomplete, particularly at metal/perovskite interfaces. This study investigates ORR on BaZrO3 (BZO) perovskite-supported metal clusters (Pt or Ag) using density functional theory (DFT) to unravel critical insights into charge redistribution at the metal/BZO interface. Energy profiles for elemental steps along two different ORR pathways—oxygen adsorption on the metal cluster surface and direct oxygen adsorption at the TPB—were calculated to explore the effects of different active sites. The results provide a deeper understanding of ORR on metal/perovskite catalysts, emphasizing the role of interfacial interactions and pathway-dependent reaction mechanisms. This work paves the way for guiding the design of high-performance electrocatalysts for ORR in terms of composition, interface design, and local environment modification for a broad range of energy applications.  more » « less
Award ID(s):
2503035
PAR ID:
10575423
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Solid State Ionics
Volume:
421
ISSN:
0167-2738
Page Range / eLocation ID:
116808
Subject(s) / Keyword(s):
Oxygen reduction reaction Metal/perovskite catalysts Interfacial interactions Charge redistribution DFT
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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