Pseudocapacitive MoOx anode material with super-high rate and ultra-long cycle properties for aqueous zinc ion batteries

Abstract Aqueous zinc-ion batteries (AZIBs) are widely concerned and considered as promising candidates for grid-scale energy storage systems due to the simple and feasible preparation process together with the demonstrated electrochemical properties, but it is still a tremendous challenge to develop new-type anode materials which can effectively overcome the zinc dendrites formation and low utilization efficiency of the typical zinc metal anodes, not to mention the ones with outstanding rate and cycle properties. Herein, for the first time, monoclinic MoOx is verified to be a novel and promising pseudocapacitive anode material for aqueous zinc-ion batteries and the MoOx shows excellent zinc ion storage abilities-especially at 10 A g−1, including ideal average potential of 0.53 V (vs. Zn2+/Zn), high discharge/charge capacities of 82.5/82.0 mAh g−1 and cycling life of 30,000 cycles. Further, zinc ion storage mechanism of the as proposed monoclinic MoOx is also studied and deduced to be: MoOx + yZn2++2ye−⇌ ZnyMoOx.