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Dopant Segregation Boosting High‐Voltage Cyclability of Layered Cathode for Sodium Ion Batteries
Author(s) -
Wang Kuan,
Wan Hui,
Yan Pengfei,
Chen Xiao,
Fu Junjie,
Liu Zhixiao,
Deng Huiqiu,
Gao Fei,
Sui Manling
Publication year - 2019
Publication title -
advanced materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.707
H-Index - 527
eISSN - 1521-4095
pISSN - 0935-9648
DOI - 10.1002/adma.201904816
Subject(s) - dopant , materials science , cathode , doping , electrochemistry , cracking , nanotechnology , chemical engineering , composite material , optoelectronics , electrode , electrical engineering , chemistry , engineering
As a widely used approach to modify a material's bulk properties, doping can effectively improve electrochemical properties and structural stability of various cathodes for rechargeable batteries, which usually empirically favors a uniform distribution of dopants. It is reported that dopant aggregation effectively boosts the cyclability of a Mg‐doped P2‐type layered cathode (Na 0.67 Ni 0.33 Mn 0.67 O 2 ). Experimental characterization and calculation consistently reveal that randomly distributed Mg dopants tend to segregate into the Na‐layer during high‐voltage cycling, leading to the formation of high‐density precipitates. Intriguingly, such Mg‐enriched precipitates, acting as 3D network pillars, can further enhance a material's mechanical strength, suppress cracking, and consequently benefit cyclability. This work not only deepens the understanding on dopant evolution but also offers a conceptually new approach by utilizing precipitation strengthening design to counter cracking related degradation and improve high‐voltage cyclability of layered cathodes.