Ultrathin Ni–Co Bimetallic Metal–Organic Framework Nanobelts for High-Performance Energy Storage

Abstract

The design and advancement of nanostructured composite materials in a one-dimensional (1D) configuration have garnered significant interest in the pursuit of high-performance supercapacitor applications. Herein, we present the synthesis of ultrathin 1D NiCo metal–organic framework (MOF) nanobelts via a solvothermal process. The resulting nanobelts exhibit a unique and uniformly distributed 1D morphology characterized by a high specific surface area (SSA) and exceptional structural stability. Electrochemical investigations reveal that the optimized 1D NiCo-MOF-31 composite shows a high specific capacitance (Cs) of 1697.5 F g–1 under 1 A g–1 current and 696.43 under 10 A g–1, with a superior cyclic performance over 5000 charging/discharging cycles. Furthermore, an asymmetric supercapacitor device (1D NiCo-MOF-31//SNAC) was constructed by using S,N-codoped activated carbon (SNAC) as the anode and 1D NiCo-MOF-31 as the cathode material. The device demonstrates an impressive energy density of 26.56 Wh kg–1 at a power density of 750 W kg–1 with remarkable cyclic stability. The exceptional electrochemical activity is due to its 1D nanobelt morphology, which offers notable advantages such as high SSA, rapid ion and electron transport, etc. These inherent benefits position nanobelts as highly promising candidates for advancing the field of high-performance supercapacitors.