Resolving the Role of Configurational Entropy in Improving Cycling Performance of Multicomponent Hexacyanoferrate Cathodes for Sodium‐Ion Batteries
Yanjiao Ma, Yanjiao Ma, Yang Hu, Yohanes Pramudya, Thomas Diemant, Qingsong Wang, Damian Goonetilleke, Yushu Tang, Bei Zhou, Horst Hahn, Wolfgang Wenzel, Maximilian Fichtner, Yuan Ma, Yuan Ma, Ben Breitung, Torsten Brezesinski
Abstract
Abstract Mn‐based hexacyanoferrate (Mn‐HCF) cathodes for Na‐ion batteries usually suffer from poor reversibility and capacity decay resulting from unfavorable phase transitions and structural degradation during cycling. To address this issue, the high‐entropy concept is here applied to Mn‐HCF materials, significantly improving the sodium storage capabilities of this system via a solid‐solution mechanism with minor crystallographic changes upon de‐/sodiation. Complementary structural, electrochemical, and computational characterization methods are used to compare the behavior of high‐, medium‐, and low‐entropy multicomponent Mn‐HCFs resolving, to our knowledge for the first time, the link between configurational entropy/compositional disorder (entropy‐mediated suppression of phase transitions, etc.) and cycling performance/stability in this promising class of next‐generation cathode materials.