Vertical-crystalline Fe-doped β-Ni oxyhydroxides for highly active and stable oxygen evolution reaction

Byeongyoon Kim, Mrinal Kanti Kabiraz, Jaewan Lee, Changhyeok Choi, Hionsuck Baik, Yousung Jung, Hyung Suk Oh, Sang Il Choi, Kwangyeol Lee

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

Abstract

The layered transition metal oxyhydroxides have received increasing interest owing to the efficient energy conversion performance and material stability during the oxygen evolution reaction (OER). In particular, Fe-doped NiOOH has shown record-high OER performance in alkaline media among various catalysts. Theoretically, undercoordinated facets including Ni4+, exposed at the edges of NiOOH, were predicted to perform highly active OER. Therefore, here we suggest a rational catalyst design, a vertical-crystalline β-Fe/NiOOH layer built on faceted Fe/Ni nanocrystals, which exposes Ni4+ sites and could improve the OER performance dramatically. Electrochemical OER tests recorded the overpotential of 210 mV at a current density of 10 mA cm−2GEO and stable operation for 5 days. In situ/operando and density functional theory studies revealed that the Ni valence cycle between +2 and +4 assisted by Fe dopant is the key engine that greatly accelerates OER kinetics and that the vertical-crystalline β-Fe/NiOOH layers on Ni octahedra are stable under harsh OER conditions.

Original languageEnglish
Pages (from-to)3585-3604
Number of pages20
JournalMatter
Volume4
Issue number11
DOIs
Publication statusPublished - 2021 Nov 3

Keywords

  • active sites
  • AEMWE
  • crystalline Fe/NiOOH
  • DFT study for Fe/NiOOH
  • electrocatalysis
  • facet control
  • heteroepitaxy
  • in-situ/operando XAS
  • MAP4: Demonstrate
  • oxygen evolution reaction

ASJC Scopus subject areas

  • Materials Science(all)

Fingerprint

Dive into the research topics of 'Vertical-crystalline Fe-doped β-Ni oxyhydroxides for highly active and stable oxygen evolution reaction'. Together they form a unique fingerprint.

Cite this