A Novel Vanadium Carbide Hybrid from Preceramic Polymer Route for Supercapacitor Application

Abstract

Polymer-derived ceramics are synthesized by the high-temperature treatment of preceramic polymers in controlled atmosphere. The properties of these ceramics are significantly influenced by the molecular composition of the precursor and the processing conditions, allowing customization of their structural and functional characteristics. Anand et al. recently demonstrated a one-step process for synthesizing nanosized (<10 nm) r-TiO2 and t-ZrO2 crystallites within an amorphous ceramic matrices by introducing Ti and Zr dopants into the preceramic polymer. Building on this, the current study in-situ synthesised vanadium carbide crystallites embedded in a silicon oxycarbide ceramic matrix by processing a modified PMPS preceramic polymer at 1000 °C in Ar atmosphere. Post-synthesis, hydrofluoric acid etching was employed to create a vanadium carbide and carbon hybrid by removing the silica domains of the ceramic. The hybrid’s structural and microstructural features were thoroughly analyzed, and its electrochemical performance was evaluated using a three-electrode setup in Na2SO4 electrolyte. Cyclic voltammetry at scan rates ranging from 2 mV s⁻¹ to 100 mV s⁻¹ showed that the charge storage mechanism is the result of the electric double layer formed at the carbon phase and the faradaic contribution from the vanadium carbide. The galvanostatic charge-discharge profile exhibited nearly triangular shape, and the maximum capacitance observed was approximately 393 F g⁻¹ at a scan rate of 2 mV s⁻¹.