Mitigating Jahn–Teller Effect in Layered Cathode Material Via Interstitial Doping for High‐Performance Sodium‐Ion Batteries

• DOI: 10.1002/smll.202301360
• Publication Date: 2023-05-11T04:33:46Z
• Authors: Hui Fang; Haocheng Ji; Jingjun Zhai; Chaoqi Wang; Chen Zhu; Guojie Chen; Mihai Chu; Taolve Zhang; Zhewen Ma; Wenguang Zhao; Wenhai Ji; Yinguo Xiao
• Keywords: Interstitial defect

Abstract Layered transition metal oxides are promising cathode materials for sodium‐ion batteries due to their high energy density and appropriate operating potential. However, the poor structural stability is a major drawback widespread application. To address this issue, B 3+ successfully introduced into tetrahedral site of Na 0.67 Fe 0.5 Mn O 2 , demonstrating effectiveness small‐radius ion doping in improving electrochemical performance. The obtained 0.04 exhibits excellent cycling performance with 88.8% capacity retention after 100 cycles at 1 C prominent rate structure‐property relationship constructed subsequently by neutron powder diffraction, situ X‐ray diffraction absorption spectroscopy, which reveal that Jahn–Teller distortion consequent P2‐P2' phase transformation effectively mitigated because occupancy interstitial site. Furthermore, it found layers stabilized dissolution suppressed, resulting Besides, attributed enhanced diffusion kinetics associated rearrangement + . This work provides novel insight action mechanism demonstrates universal approach improve properties P2‐type manganese‐based sodium materials.