The electrochemical performance of Cu3[Fe(CN)6]2 as a cathode material for sodium-ion batteries

Prussian blue analogues (PBAs) have recently attracted extensive interests as a new class of cathode materials for rechargeable batteries. Copper hexacyanoferrate, a typical Prussian blue analogue with the chemical formula Cu-3[Fe(CN)(6)](2), has been synthesized by solution precipitation method and investigated as a cathode material for sodium-ion batteries. The galvanostatic cycling tests show a specific capacity of 44 mA h g(-1) at a current density of 20 mA g(-1) and the capacity retention can be 57.1% after 50 cycles, The material can also deliver a specific capacity of 37 mA h g(-1) and 25 mA h g(-1) at a rate of 50 mA g(-1) and 100 mA g(-1), respectively. Furthermore, the material exhibits a high reduction peak at 3.32 V vs. Na+/Na, which brings more power to sodium-ion batteries. The data indicate the as-prepared material is capable of realizing the single electron redox capacity due to the reduction of Fe3+/Fe2+. All of the findings suggest a possible use of Cu-3[Fe(CN)(6)](2) nanoparticles as environmental friendly and cost-effective cathode material, which also open new perspectives to develop cathode materials for sodium-ion batteris. (C) 2016 Elsevier Ltd. All rights reserved.