The development of hierarchical metal–organic frameworks (MOFs) consisting of interconnected nanostructures is of great importance for biosensors, gas separation, energy storage, healthcare and catalysis as a consequence of efficient mass transfer kinetics by means of mesopores. We outline a simple strategy to modify zeolitic imidazolate framework-8 (ZIF-8) with porous V2O5 to achieve V2O5 incorporated ZIF-8 nanocomposites through a simple in situ synthesis method. Powder X-ray diffraction and infrared spectroscopy analyses confirmed the formation of the hybrid nanocomposites. A strong band at 421 cm−1 corresponding to Zn–N stretching has been observed due to the bonding of the zinc atoms in the ZIF-8 structure with the nitrogen atoms of the 2-methylimidazole linker during the formation of V2O5@ZIF-8 composites. The nanocomposites have been morphologically characterized using scanning electron microscopy and transmission electron microscopy analyses. The electrochemical performance is evaluated based on high potential redox reactions occurring in a blend of additive redox electrolytes in a potential window of 0.85 V, attaining a capacity of 802.88 F g−1 at 10 A g−1. These hybrid nanocomposites have higher electrochemical capacitance than ZIF-8 nanocrystals as advanced materials for supercapacitor electrodes. This fascinating electrochemical capability is majorly associated with the synergistic effect of the Zn-MOF and vanadia nanoparticles. These characteristics make our V2O5@ZIF-8 nanocomposite an ideal MOF-based electrode for high-performance energy storage applications. An asymmetric supercapacitor device fabricated using the redox additive electrolyte shows energy densities and power densities of 8.56 Wh kg−1 and 1923.07 W kg−1, respectively.
17 February 2023 in International Journal of Hydrogen Energy