Redox-Driven Spin Transition in a Layered Battery Cathode Material

Eriko Watanabe, Wenwen Zhao, Akira Sugahara, Benoit Mortemard De Boisse, Laura Lander, Daisuke Asakura, Yohei Okamoto, Takashi Mizokawa, Masashi Okubo, Atsuo Yamada*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

16 Citations (Scopus)


A spin transition between high-spin (HS) and low-spin (LS) states in a solid can occur when the energies of two spin configurations intersect, which is usually caused by external perturbations such as temperature, pressure, and magnetic fields, with substantial influence to its physical and chemical properties. Here, we discover the electrochemical "redox reaction" as a new driving force to induce reversible HS-LS spin transition. Although reversible solid-state redox reaction has been thoroughly investigated as the fundamental process in battery electrode materials, coupling between redox reactions and spin transitions has not been explored. Using density functional theory calculations, we predicted the existence of redox-driven spin transition occurring exclusively for the Co 3+ /Co 2+ redox couple in layered transition-metal oxides, leading to a colossal potential hysteresis (>1 V) between the cathodic (LS Co 3+ to LS Co 2+ ) and anodic (HS Co 2+ to HS Co 3+ ) reactions. The predicted potential hysteresis associated with the spin transition of Co was experimentally verified for Na x Ti 0.5 Co 0.5 O 2 by monitoring the electrochemical potential, local coordination structure, electronic structure, and magnetic moment.

Original languageEnglish
Pages (from-to)2358-2365
Number of pages8
JournalChemistry of Materials
Issue number7
Publication statusPublished - 2019 Apr 9

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Materials Chemistry


Dive into the research topics of 'Redox-Driven Spin Transition in a Layered Battery Cathode Material'. Together they form a unique fingerprint.

Cite this