Polymer-mediated low-temperature synthesis of CoWO₄ particles for supercapacitor application

The electrochemical supercapacitor has shown to be a reliable and innovative type of energy storage technology over the years. Recent research has shown that CoWO₄ is a potential material for supercapacitor applications because of its unique characteristics, which make it suitable for energy storage. CoWO₄ particles are synthesized using a hydrothermal method with PVP as the capping agent, followed by a 2-hour post-heat treatment at 300 ℃. The synthesized powder was characterized through X-ray diffraction (XRD), scanning electron microscopy, Raman spectroscopy, and electrochemical techniques. XRD analysis revealed the crystalline nature of the sample. The indexed XRD peaks conform to a monoclinic crystal framework of CoWO₄ with a space group of P2/c. SEM image indicates significant structural agglomeration in the synthesized CoWO₄ material. The CoWO₄ electrode indicates a high specific capacitance of 135 F/g at 10 mV/s in 1 M KOH electrolyte between − 0.15 V and 0.6 V potential window. Galvanostatic charge-discharge measurements reveal a specific capacitance of 115 F/g at 0.23 A/g current density and retains 96.12% capacitance even after 1000 cycles Moreover, the improved potential window is observed during the cyclic voltammetry measurements.