CuCo‐Based Mixed Metal–Organic Framework: A Blueprint for Achieving High Specific Capacitance in Supercapacitors

Abstract

Abstract The rational design of metal–organic frameworks (MOFs) with controlled composition provides a versatile route for developing high‐performance electrode materials for supercapacitors. In this study, a bimetallic CuCo‐MOF is synthesized via a one‐step solvothermal process using trimesic acid as an organic linker, enabling uniform incorporation of Cu and Co metal centers within the framework. Structural and morphological characterizations using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) confirm the successful formation and homogeneity of the composite structure. Electrochemical evaluations in 3 M KOH, including cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS), reveal that the CuCo‐MOF electrode delivers a high specific capacitance of 1578 F g −1 , significantly surpassing the single‐metal Cu‐MOF (522 F g −1 ) and Co‐MOF (592 F g −1 ) counterparts. The electrode exhibits remarkable cycling stability with 87.8% capacitance retention after 4000 cycles and a consistent Coulombic efficiency of 92.8%. Furthermore, an asymmetric supercapacitor (ASC) device employing CuCo‐MOF as the positive electrode and activated carbon (AC) as the negative electrode achieves an energy density of 28 Wh kg −1 at a power density of 700 W kg −1 , while maintaining 83.9% capacitance retention over 3000 cycles. These results demonstrate that the CuCo‐MOF possesses superior electrochemical activity, stability, and scalability, underscoring its strong potential as a next‐generation electrode material for advanced energy storage systems.