Highly crystalline Prussian blue cubes filled with tin oxide as anode materials for lithium-ion batteries

Prussian blue (PB), which is typically used as a cathode for sodium-ion batteries, has seldomly been studied as anode material for lithium-ion batteries (LIBs). In this study, a one-step hydrothermal method has been used to prepare hierarchical highly crystalline 3D PB cubic structure anode material, which were subsequently filled with tin oxide (SnO2) nanoparticles. The effective growth mechanism and improvement in the surface structure of iron ferricyanide and bare PB are compared with previously reported PB-based nanocomposite materials. The specific capacity of the PB@SnO2 material was higher than that of PB and structural stability was achieved after 300 cycles at 50 mA g(-1). Furthermore, the unique structure of PB@SnO2 was studied, and the effect of the structure on the electrochemical performance of PB@SnO2 as an LIB anode was evaluated. The proposed electrode presented significantly improved the stability enhanced the active sites, and delivered a high specific capacity of -910 mAh/g. The N atoms of the ammonium salt used to fabricate PB yielded N-doped carbon, which served as a cushion, effectively preventing particle aggregation and volume expansion of PB@SnO2 during cycling.

Automated summary

In this study, hierarchical highly crystalline 3D PB cubic structure anode material was prepared using a one-step hydrothermal method, and the surface structure was improved by filling with SnO2 nanoparticles. The PB@SnO2 material showed higher specific capacity and structural stability, and the unique structure improved the electrochemical performance of LIBs.