Microwave-assisted hydrothermal synthesis of CeVO₄ nanostructures: exploring their applicability in supercapacitor technologies

Herein, we investigated CeVO₄ nanostructures synthesized using a microwave-assisted hydrothermal method, focusing on their structural and electrochemical properties for potential supercapacitor applications. Notably, the selected synthesis method yielded a material that displays lattice spacing consistent with the (200) plane of the tetragonal CeVO₄ structure, as confirmed by high-resolution transmission electron microscopy and corroborated by X-ray diffraction analysis. In addition, EDX spectroscopy demonstrated the high purity of the sample, with only Ce, V, and O elements presented, and XPS analysis revealed the chemical composition of the elements and oxidation states on the surface, with Ce³⁺, Ce⁴⁺, and V⁵⁺ identified. Following, cyclic voltammetry tests indicated pseudocapacitive behavior with well-defined redox peaks and good capacitive behavior and stability; then, galvanostatic charge–discharge profiles exhibited high specific capacitances at various current densities. After such analyses, an asymmetric supercapacitor was assembled using activated carbon as a cathode, and it demonstrated an excellent energy density value of 424.43 Wh kg⁻¹ at a power density of 2783.11 W kg⁻¹ (1 A g⁻¹ in 2.0 M KOH). Thus, the comprehensive structural and electrochemical characterizations provided valuable insights into the material’s potential for energy storage systems.