@article{Yuan2024, 
author = {Tao Yuan and Xiaopan Fu and Yuan Wang and Mingjie Li and Shuixin Xia and Yuepeng Pang and Shiyou Zheng},
title = {Enhanced conductivity and stability of Prussian blue cathodes in sodium-ion batteries by surface vapor-phase molecular self-assembly},
year = {2024},
journal = {Nano Research},
volume = {17},
number = {5},
pages = {4221-4230},
keywords = {surface modification, cathode, sodium-ion battery, Prussian blue analogs, vapor-phase molecular self-assembly},
url = {https://www.sciopen.com/article/10.1007/s12274-023-6394-3},
doi = {10.1007/s12274-023-6394-3},
abstract = {With many merits such as facile synthesis, economy, and relatively high theoretical capacity, Prussian blue analogs (PBAs) are considered promising cathode materials for sodium-ion batteries (SIBs). However, their practical applications still suffer from a low actual specific capacity and inferior stability owing to the imperfect crystallinity, irreversible phase transition, and low intrinsic conductivity. Herein, a surface-modification technique for vapor-phase molecular self-assembly was developed to prepare Fe-based PBAs, specifically sodium iron hexacyanoferrate (NaFeHCF), with a uniform conductive polymer protective layer of polypyrrole (PPy) on the surface, resulting in NaFeHCF@PPy. The incorporation of a PPy protective layer not only improves the electronic conductivity of NaFeHCF@PPy, but also effectively mitigates the dissolution of Fe-ions during cycling. Specifically, this advanced vapor-phase technique avoids Fe2+ oxidation and Na+ loss during liquid-phase surface modification. The NaFeHCF@PPy exhibited a remarkably enhanced cycling performance, with capacity retentions of 85.6% and 69.1% over 500 and 1000 cycles, respectively, at 200 mA/g, along with a superior rate performance up to 5 A/g (fast kinetics). Additionally, by adopting this strategy for Mn-based PBAs (NaMnHCF@PPy), we further demonstrated the universality of this method for PBA cathodes in SIBs.}
}