Boosting the Reversibility and Kinetics of Anionic Redox Chemistry in Sodium-Ion Oxide Cathodes via Reductive Coupling Mechanism

Activating anionic redox chemistry in layered oxide cathodes is a paradigmatic approach to devise high-energy sodium-ion batteries. Unfortunately, excessive oxygen redox usually induces irreversible lattice oxygen loss and cation migration, resulting in rapid capacity and voltage fading and sluggish reaction kinetics. Herein, the reductive coupling mechanism (RCM) of uncommon electron transfer from oxygen to copper ions is unraveled in a novel P2-Na0.8Cu0.22Li0.08Mn0.67O2 cathode for boosting the reversibility and kinetics of anionic redox reactions. The resultant strong covalent Cu–(O–O) bonding can efficaciously suppress excessive oxygen oxidation and irreversible cation migration. Consequently, the…

• NN
  National Natural Science Foundation of China

  Awards: 22103057, 52372171, 22075016
• UO
  University of Science and Technology Beijing

  Award: FRFIDRY-21-011
• HE
  Higher Education Discipline Innovation Project

  Award: B170003
• FR
  Fundamental Research Funds for the Central Universities

  Awards: QNXM20220060, FRF-TP-20-020A3
• NP
  National Program for Support of Top-notch Young Professionals
• SK
  State Key Laboratory for Advanced Metals and Materials

  Award: 2022Z-17