Hierarchical sodium-rich Prussian blue hollow nanospheres as high-performance cathode for sodium-ion batteries
sodium-rich, sodium iron hexacyanoferrate, hollow nanospheres, cathode, sodium-ion batteries
ABSTRACT Recently, Prussian blue and its analogues (PBAs) have attracted tremendous attention as cathode materials for sodium-ion batteries because of their good cycling performance, low cost, and environmental friendliness. However, they still suffer from kinetic problems associated with the solid-state diffusion of sodium ions during charge and discharge processes, which leads to low specific capacity and poor rate performances. In this work, novel sodium iron hexacyanoferrate nanospheres with a hierarchical hollow architecture have been fabricated as cathode material for sodium-ion batteries by a facile template method. Due to the unique hollow sphere morphology, sodium iron hexacyanoferrate nanospheres can provide large numbers of active sites and high diffusion dynamics for sodium ions, thus delivering a high specific capacity (142 mAh/g), a superior rate capability, and an excellent cycling stability. Furthermore, the sodium insertion/extraction mechanism has been studied by in situ X-ray diffraction, which provides further insight into the crystal structure change of the sodium iron hexacyanoferrate nanosphere cathode material during charge and discharge processes.
Tsinghua University Press
Xiao Tang,Hao Liu,Dawei Su,Peter H. L. Notten,Guoxiu Wang, Hierarchical sodium-rich Prussian blue hollow nanospheres as high-performance cathode for sodium-ion batteries. NanoRes.2018, 11(8): 3979–3990