Synthesis of FeVO4 nanoparticles using sol-gel auto-combustion method and their application in supercapacitors

Iron vanadate (FeVO₄) nanoparticles (NPs) were synthesized using the sol-gel auto-combustion technique, yielding a triclinic nanostructure as revealed by X-ray diffraction (XRD). The average size, crystalline structure, and morphology of the nanoparticles were analyzed using field emission scanning electron microscopy (FESEM). Energy-dispersive X-ray spectroscopy (EDX) was used to investigate the elemental content and purity of the FeVO₄ NPs. Fourier transform infrared spectroscopy (FTIR) confirmed the surface stretching frequency of the FeVO₄ NPs. Using a doctor blade, the produced FeVO₄ NPs were applied to the surface of a stainless steel (SS) substrate. The fabricated electrode was examined using GCD, EIS, and CV techniques. The absorption spectra exhibited strong absorbance in the visible range, with a band gap of 3.43 eV. Additionally, the FeVO₄ electrode showed supercapacitor properties, with a maximum specific capacitance of 1151.05 F/g in a 1 M KOH electrolyte at a scan rate of 5 mV/s. These results indicate that the prepared FeVO₄ electrode is promising for supercapacitor application due to their excellent electrochemical performance.