Interior-Confined Vacancy in Potassium Manganese Hexacyanoferrate for Ultra-Stable Potassium-Ion Batteries

Interior-Confined Vacancy in Potassium Manganese Hexacyanoferrate for Ultra-Stable Potassium-Ion Batteries

© 2024 The Authors. Advanced Materials published by Wiley‐VCH GmbH.

Bibliographische Detailangaben
Veröffentlicht in:Advanced materials (Deerfield Beach, Fla.). - 1998. - 36(2024), 15 vom: 12. Apr., Seite e2310428
1. Verfasser: Li, Xiaoxia (VerfasserIn)
Weitere Verfasser: Guo, Tianqi, Shang, Yang, Zheng, Tian, Jia, Binbin, Niu, Xiaogang, Zhu, Yujie, Wang, Zhongchang
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2024
Zugriff auf das übergeordnete Werk:Advanced materials (Deerfield Beach, Fla.)
Schlagworte:Journal Article Fe(CN)6 vacancies K2Mn[Fe(CN)6] Mn dissolution potassium‐ion batteries surface vacancy repairs
Beschreibung
Zusammenfassung:© 2024 The Authors. Advanced Materials published by Wiley‐VCH GmbH.
Metal hexacyanoferrates (HCFs) are viewed as promising cathode materials for potassium-ion batteries (PIBs) because of their high theoretical capacities and redox potentials. However, the development of an HCF cathode with high cycling stability and voltage retention is still impeded by the unavoidable Fe(CN)6 vacancies (VFeCN) and H2O in the materials. Here, a repair method is proposed that significantly reduces the VFeCN content in potassium manganese hexacyanoferrate (KMHCF) enabled by the reducibility of sodium citrate and removal of ligand H2O at high temperature (KMHCF-H). The KMHCF-H obtained at 90 °C contains only 2% VFeCN, and the VFeCN is concentrated in the lattice interior. Such an integrated Fe-CN-Mn surface structure of the KMHCF-H cathode with repaired surface VFeCN allows preferential decomposition of potassium bis(fluorosulfonyl)imide (KFSI) in the electrolyte, which constitutes a dense anion-dominated cathode electrolyte interphase (CEI) , inhibiting effectively Mn dissolution into the electrolyte. Consequently, the KMHCF-H cathode exhibits excellent cycling performance for both half-cell (95.2 % at 0.2 Ag-1 after 2000 cycles) and full-cell (99.4 % at 0.1 Ag-1 after 200 cycles). This thermal repair method enables scalable preparation of KMHCF with a low content of vacancies, holding substantial promise for practical applications of PIBs
Beschreibung:Date Revised 11.04.2024
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.202310428