Electrochemical insights of cost-effectively synthesized vanadium MOF: unlocking a new path for supercapacitor electrode materials

Abstract

Vanadium metal–organic frameworks have made significant strides in energy storage devices, especially supercapacitors. However, the high cost of vanadium precursors and their toxicity has become a barrier to their wide application. To overcome this, ammonium metavanadate is used as a low-cost precursor for the synthesis of vanadium MOF through a simple solvothermal process and its application in supercapacitors for the first time. This cost-effectively prepared vanadium MOF (V MOF) features a branched rod-like morphology and is subjected to various electrochemical tests to assess its potential as an electrode material. V MOF exhibited a three-electrode specific capacitance (C_SC) of 43 Fg⁻¹ at 1 A g⁻¹ and a charge transfer resistance (R_ct) of 10.7 Ω. It exhibited excellent stability performance by retaining 94% of its coulombic efficiency after 10,000 cycles. An asymmetric supercapacitor device was fabricated using V MOF, which exhibited an R_ct of 11.4 Ω. The device delivered an energy density of 4.5 W h kg⁻¹ at a power density of 330.6 W kg⁻¹ with a C_SC of 4.1 Fg⁻¹ at 1 Ag⁻¹ and retained 87% of its energy efficiency after 8000 cycles. The formation of V MOF from the low-cost precursor shows that this can be an effective and cost-effective electrode material, hence opening further research and development in the area.

Graphical Abstract