Utilizing an autogenously protective atmosphere to synthesize a Prussian white cathode with ultrahigh capacity-retention for potassium-ion batteries

Abstract

A facile, low-cost precipitation method, utilizing an autogenously protective atmosphere without the assistance of an inert atmosphere, is proposed to synthesize nano-sized Prussian white K_1.62Fe[Fe(CN)₆]_0.92·0.33H₂O. The cathode delivers a high capacity of 120.9 mA h g⁻¹ at 50 mA g⁻¹ and an ultrahigh capacity retention of 98.2% after 100 cycles.