NiCo MOF@Carbon Quantum Dots Anode with Soot Derived Activated Carbon Cathode: An Efficient Asymmetric Configuration for Sustainable High‐Performance Supercapacitors

Abstract

AbstractMetal‐organic frameworks (MOFs) exhibit excellent crystalline, hierarchical porous structures and have garnered great scientific interest as a key material for supercapacitor applications. However, the low conductivity of MOFs poses a great challenge to fully utilize their potential. Carbon quantum dots (CQDs) prepared from waste edible soybean oil have been skillfully incorporated into NiCo MOF to enhance supercapacitive performance with its high electronic conductivity and rapid charge transfer kinetics. Symmetrical, spherical CQDs synthesized using the hydrothermal method have been decorated on NiCo MOF nanosheets using a facile solvothermal technique to form the NiCo MOF@CQDs composite. The new composite retains the desirable crystalline structure and hierarchical porosity of MOFs, while the integration of CQDs contributes to enhanced conductivity, yielding a superior specific capacitance of 1063.02 Fg−1 (0.5 Ag−1). An asymmetric supercapacitor device has been fabricated using NiCo MOF@CQDs as positive electrode and waste soybean oil‐derived activated‐carbon as negative electrode. The assembled device shows a remarkable energy and power density of 30.61 Whkg−1 and 0.62 kWkg−1, respectively. Moreover, the device demonstrates a promising Coulombic efficiency of 84.53%, with capacitance retention of 88.61% over 5000 charge–discharge cycles. This work highlights existing challenges and potential sustainable solutions in the realm of emerging energy storage devices.