Influence of the Thermal Treatment on the Structure and Cycle Life of Copper Hexacyanoferrate for Aqueous Zinc-Ion Batteries

Copper hexacyanoferrate (CuHCF) has become an attractive Zn2+ insertion material as a positive electrode in aqueous zinc-ion batteries thanks to its high reversibility towards (de-)insertion, simple, inexpensive and easily scalable synthesis route, low toxicity, working potential. It is known that the physiochemical properties of CuHCF can be modified by manipulating parameters. However, effect these parameters on material’s electrochemical performance cycle life needs further investigation. Here, structure composition treated at different temperatures are studied through crystallographic, compositional, thermogravimetric analyses. The resulting powders were galvanostatically cycled assess their relation annealing temperature. results showed annealed electrodes exhibited longer while maintaining coulombic efficiency ≥ 99.5%. longest was achieved 100 °C.