Bimetallic MOF-derived manganese-cobalt composite oxide as high-performance zinc-ion batteries cathode

Abstract

The designing cathode materials of aqueous zinc-ion batteries (AZIBs) with high performance is significant challenges in the development of AZIBs. Metal–organic frameworks (MOFs) are considered prime candidates for cathode modification and high-performance cathode materials. Herein, a two-step hydrothermal method was employed to fabricate a bimetallic metal–organic framework MnCo-MOF on carbon cloth. The resulting precursor was calcined to produce a cathode composite MnCo₂O₄. As a cathode for AZIBs, MnCo₂O₄/CC exhibited an average specific capacity of 280.6 mAh/g. Upon completion of the cycle at a current density of 0.2 A/g, the specific capacity measured 275.1 mAh/g (retaining 98% of its initial capacity), while maintaining a coulombic efficiency of approximately 98.5%. The excellent cycling performance, superior specific capacity, and superb coulombic efficiency are ascribed to the concerted influence of the polymetallic ions. The micro and nano scale interconnected block structure of MnCo₂O₄ facilitates interaction between electrode substance and the electrolyte. This research broadens the selection of cathode material and offers valuable guidance for designing high-performance cathode materials for AZIBs.