A potassium-rich iron hexacyanoferrate/dipotassium terephthalate@carbon nanotube composite used for K-ion full-cells with an optimized electrolyte

K-ion batteries, as an emerging battery system, have attracted tremendous attention in the research community. Herein, we report a K-ion full-cell based on a nano-sized K1.92Fe[Fe(CN)(6)](0.94)center dot 0.5H(2)O cathode, dipotassium terephthalate (K2TP)@carbon nanotube (CNT) anode and an optimized electrolyte. K1.92Fe[Fe(CN)(6)](0.94)center dot 0.5H(2)O delivers a high capacity of 133 mA h g(-1) with 92.8% capacity retention after 200 cycles and high coulombic efficiency of 98.5%. The side reactions of K metal with the electrolyte are suppressed in KClO4/propylene carbonate (PC). The K2TP nanosheets grown in situ on the CNT show a high reversible capacity of about 250 mA h g(-1) and an ultra-high rate capability. The full-cells based on them are well cycled in a DME-based electrolyte and show a great promise for large-scale energy storage.