Synergistic effect of carbon nanotube and tri-metallic MOF nanoarchitecture for electrochemical high-performance asymmetric supercapacitor applications and their charge storage mechanism

Abstract

To develop innovative energy-storage devices, metal-organic frameworks (MOFs) with various nano-geometries must be rationally combined. In this research, a trimetallic-based MOF with varying ratios of carbon nanotubes (CNT) was synthesized and optimized for use in electrochemical supercapacitor devices. The composite material has a corrugated-layered structure that allows for fast ion transport and electrolyte storage. The synergistic features of CNT and MOF, along with the stronger redox reactions of multimetallic ionic species, enable effective charge storage. The 1D nanotube form of CNT provides stability and electrical conductivity. MOF-CNT(5 %) showed a higher capacitive efficiency than MOF due to its high specific capacitance and rate capacity (86.1 % retention at 5 A/g). The MOF-CNT(5 %)//ACarbon composite exhibited a capacitance of 166.4 F/g at 1 A/g, 79.2 % retention after 10,000 charging/discharging cycles, a high-power density of 501.5 W/kg, and an energy density of 23.6 Wh/kg, making it a potential nanomaterial for asymmetric supercapacitors. Dunn's and Trasatti's model were used to extract regression parameters and capacitive-diffusive contributions of the supercapacitor.