Fabrication of Flower-Like Bismuth Vanadate Hierarchical Spheres for an Improved Supercapacitor Efficiency

A cost-effective and simple method is developed for preparing flower-like hierarchical spheres of semiconductor oxide material. Efficient self-assembly of BiVO4 flower-like hierarchical spheres was prepared by simple hydrothermal method followed by calcination at 500 °C. X-ray diffraction (XRD) studies distinguish diffraction planes of monoclinic BiVO4 phase, which is further convinced by Field emission Scanning Electron Microscope (FESEM) analysis. The electronic and optical properties of BiVO4 were studied in X-ray photoelectron spectroscopy (XPS) and UV-Visible spectroscopy. XPS analysis confirmed the binding energy relations and the formation of BiVO4, also an increase in Bi−O, V−O bond strengths in BiVO4. The remarkable efficiency of pseudocapacitor electrode materials depends on the consistent fabrication of nano architectures. The carbon-free BiVO4 electrodes show a higher specific capacitance of 1203 F/g at 2 A/g, without detectable degradation after 2000 cycles and the beneficial cycling stability achieved because of the distinctive porous hierarchical architecture electrochemical activity. Our synthetic method suggests a simple procedure for the design and fabrication of bismuth vanadate hierarchical nano architectures, encouraging electrochemical energy storage. These nanocomposites could be utilized as anode materials in lithium-ion batteries.