Deakin University
Browse

File(s) not publicly available

Impact of Surface Defects on LaNiO3 Perovskite Electrocatalysts for the Oxygen Evolution Reaction

journal contribution
posted on 2023-02-16, 01:22 authored by H Arandiyan, SS Mofarah, Y Wang, C Cazorla, D Jampaiah, M Garbrecht, K Wilson, AF Lee, C Zhao, T Maschmeyer
Perovskite oxides are regarded as promising electrocatalysts for water splitting due to their cost-effectiveness, high efficiency and durability in the oxygen evolution reaction (OER). Despite these advantages, a fundamental understanding of how critical structural parameters of perovskite electrocatalysts influence their activity and stability is lacking. Here, we investigate the impact of structural defects on OER performance for representative LaNiO3 perovskite electrocatalysts. Hydrogen reduction of 700 °C calcined LaNiO3 induces a high density of surface oxygen vacancies, and confers significantly enhanced OER activity and stability compared to unreduced LaNiO3; the former exhibit a low onset overpotential of 380 mV at 10 mA cm−2 and a small Tafel slope of 70.8 mV dec−1. Oxygen vacancy formation is accompanied by mixed Ni2+/Ni3+ valence states, which quantum-chemical DFT calculations reveal modify the perovskite electronic structure. Further, it reveals that the formation of oxygen vacancies is thermodynamically more favourable on the surface than in the bulk; it increases the electronic conductivity of reduced LaNiO3 in accordance with the enhanced OER activity that is observed.

History

Journal

Chemistry - A European Journal

Volume

27

Pagination

14418-14426

Location

Germany

ISSN

0947-6539

eISSN

1521-3765

Language

en

Publication classification

C1.1 Refereed article in a scholarly journal

Issue

58

Publisher

Wiley

Usage metrics

    Research Publications

    Categories

    No categories selected

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC