Na 2 FePO 4 F/Biocarbon Nanocomposite Hollow Microspheres Derived from Biological Cell Template as High‐Performance Cathode Material for Sodium‐Ion Batteries

• Published in: Chemistry : a European journal 2021-06, Vol.27 (35), p.9022-9030
• Main Authors: Li, Haiming, Wang, Tailin, Wang, Xue, Li, Guangda, Shen, Jianxing, Chai, Jinling
• Format: Article
• Language: English
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.202100096

We have successfully synthesized Na 2 FePO 4 F/biocarbon nanocomposite hollow microspheres from Fe III precursor as cathodes for sodium‐ion batteries through self‐assembly of yeast cell biotemplate and sol‐gel technology. The carbon coating on the nanoparticle surface with a mesoporous structure enhances electron diffusion into Na 2 FePO 4 F crystal particles. The improved electrochemical performance of Na 2 FePO 4 F/biocarbon nanocomposites is attributed to the larger electrode−electrolyte contact area and more active sites for Na + on the surface of hollow microspheres compared with those of Na 2 FePO 4 F/C. The Na 2 FePO 4 F/biocarbon nanocomposite exhibits a high initial discharge capacity of 114.3 mAh g −1 at 0.1 C, long‐cycle stability with a capacity retention of 74.3 % after 500 cycles at 5 C, and excellent rate capability (70.2 mAh g −1 at 5 C) compared with Na 2 FePO 4 F/C. This novel nanocomposite hollow microsphere structure is suitable for improving the property of other cathode materials for high‐power batteries.