Ni‐Based Coordination Polymer as a Promising Anode Material for Potassium Batteries

Ni‐based coordination polymer derived from 3,3′‐diaminobenzidine (Ni‐DAB) is reported as a stable potassium battery anode working in the safe voltage window of 0.4–2.0 V versus K + /K. At a low current density of 50 mA g −1 , specific discharge capacity of 183 mA h g −1 is reached. Capacity of 158 mA h g −1 is obtained at 1 A g −1 , whereas capacity decay is only 0.014% per cycle over 600 cycles, which is among the best cycling stability results reported for electrode materials used in potassium batteries.