Porous Carbon@Ferric Silicate Hollow Spheres for Enhanced Lithium and Sodium Storage
Tianbao Cui, Chunjuan Tang, Jili Li, Bo Wang, Zhiyu Min, Jia Liu, Jinli Ning, Kun Xiao, Zhengjun Zong, Yongsheng Zhang
Abstract
The intrinsic poor conductivity and large volume variation of ferric silicate severely hinder its practical application. Herein, a unique double‐shell‐structured amorphous porous carbon@ferric silicate hierarchical hollow sphere (PC@FS) is designed to improve its electrochemical performance. The amorphous feature of PC@FS is favorable for Li + /Na + diffusion and avoids the structure collapse. FS nanosheets shorten the transport path of lithium/sodium ions. The hollow carbon spheres not only boost the conductivity but also accommodate volume variation. Besides, the heterointerface of PC@FS exhibits interfacial lithium/sodium storage. The synergistic effects bestow PC@FS enhanced lithium and sodium storage with high reversible capacity, excellent rate performance, and remarkable cycling stability. It manifests a capacity as high as 625.7 mAh g −1 at 5 A g −1 after 1000 cycles for lithium‐ion batteries and 315.7 mAh g −1 at 0.05 A g −1 after 50 cycles for sodium‐ion batteries.