Antiferromagnetic Inverse Spinel Oxide LiCoVO4 with Spin-Polarized Channels for Water Oxidation

Riccardo Ruixi Chen, Yuanmiao Sun, Samuel Jun Hoong Ong, Shibo Xi, Yonghua Du, Chuntai Liu, Ovadia Lev, Zhichuan J. Xu*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

101 Scopus citations

Abstract

Exploring highly efficient catalysts for the oxygen evolution reaction (OER) is essential for water electrolysis. Cost-effective transition-metal oxides with reasonable activity are raising attention. Recently, OER reactants' and products' differing spin configurations have been thought to cause slow reaction kinetics. Catalysts with magnetically polarized channels could selectively remove electrons with opposite magnetic moment and conserve overall spin during OER, enhancing triplet state oxygen molecule evolution. Herein, antiferromagnetic inverse spinel oxide LiCoVO4 is found to contain d7 Co2+ ions that can be stabilized under active octahedral sites, possessing high spin states S = 3/2 (t2g 5eg 2). With high spin configuration, each Co2+ ion has an ideal magnetic moment of 3 µB, allowing the edge-shared Co2+ octahedra in spinel to be magnetically polarized. Density functional theory simulation results show that the layered antiferromagnetic LiCoVO4 studied contains magnetically polarized channels. The average magnetic moment (µave) per transition-metal atom in the spin conduction channel is around 2.66 µB. Such channels are able to enhance the selective removal of spin-oriented electrons from the reactants during the OER, which facilitates the accumulation of appropriate magnetic moments for triplet oxygen molecule evolution. In addition, the LiCoVO4 reported has been identified as an oxide catalyst with excellent OER activity.

Original languageAmerican English
Article number1907976
JournalAdvanced Materials
Volume32
Issue number10
DOIs
StatePublished - 1 Mar 2020

Bibliographical note

Publisher Copyright:
© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Keywords

  • antiferromagnetic materials
  • electrocatalysis
  • inverse spinel oxide
  • spin polarized channels
  • water oxidation

Fingerprint

Dive into the research topics of 'Antiferromagnetic Inverse Spinel Oxide LiCoVO4 with Spin-Polarized Channels for Water Oxidation'. Together they form a unique fingerprint.

Cite this