Preparation and Electrochemical Characterization of ZnRE(Y, La, Dy) Bimetallic MOFs for Supercapacitor Electrodes

Three bimetallic coordination frameworks, ZnDy-MOF, ZnY-MOF, and ZnLa-MOF, were synthesized through hydrothermal method and characterized by XRD and SEM. All three exhibited smooth rod-like morphologies with uniform size distributions, indicating high sample purity. Electrochemical performance was evaluated using cyclic voltammetry, galvanostatic charge–discharge, electrochemical impedance spectroscopy, and cyclic stability testing. All three MOFs demonstrated good electrochemical stability and energy storage capability. Among them, ZnLa-MOF showed significantly superior performance, including longer discharge time, higher specific capacitance, and better rate capability. When assembled into an asymmetric device, ZnLa-MOF delivered an energy density of 60.12 Wh kg–1 at a power density of 412.24 W kg–1. These results highlight its potential for application in high-performance supercapacitors.