Iron phosphate hydroxide hydrate as a novel anode material for advanced aqueous full potassium-ion batteries

The development of aqueous potassium-ion batteries is limited by the lack of suitable anode materials. Here, a novel anode material, iron phosphate hydroxide hydrate Fe1.19PO4(OH)(0.18)(H2O)(0.3), was introduced and synthesized, which delivers considerable reversible capacities of 80 mA h g(-1) at 0.05 A g(-1). An aqueous full potassium-ion battery assembled with the K2Zn3(Fe(CN)(6))(2) cathode exhibits 80% capacity retention after 1000 cycles.

Automated summary

The study introduces and synthesizes a novel anode material for aqueous potassium-ion batteries, which demonstrates significant reversible capacity and shows good capacity retention in cyclic tests when assembled with a specific cathode material.