Synergistic effect of 3D porous tri-metallic MOF based electrode materials for highly stable asymmetric supercapacitors

Abstract

Metal-organic frameworks (MOFs) have captured huge consideration owing to their high porosity structure and large surface area for their utilization in supercapacitors. The synthesis parameters play a vital role in the morphological and structural features of MOFs. Herein, a trimetallic metal-organic framework with the morphology of flower-based hierarchical microspheres has been synthesized by solvothermal method with optimization of the reaction duration. The hierarchical structure with connected nanosheets can provide more electroactive sites that lead to exceptional electrochemical performance. NiCoMn-MOF prepared with a reaction time of 48 h (MOF-48) delivers the specific capacitance of 1905 F/g (1 A/g) with rate capability of 71.52 % (10 A/g). Furthermore, MOF-48||Act-C asymmetric supercapacitor displays a remarkable capacitance of 226 F/g (1 A/g) and keeps 97 % of initial capacitance after 15000 continuous cycles. This asymmetric device has a power density of 6945.4 W/kg (10 A/g) and an energy density of 61.52 Wh/kg (1 A/g). Therefore, this study offers an effective technique to improve the electrochemical effectiveness of MOF-based electrodes for high-performance supercapacitors.