3D-architectured spherical Ce₂Mo₅O₁₆ by a time-dependent hydrothermal process and their energy storage application

A hydrothermal process generates cerium (III) molybdate microspheres configured with microflakes as the active electrode materials for high performance supercapacitors. We investigate the influence of reaction time on the morphological properties of cerium (III) molybdate nanostructures and reveal the spherical structure as flaky structures of cerium molybdate (CMO)-12 h composite with a controlled size of 2–3 µm. The large surface area of the CMO-12 h composite greatly contributes to the high energy storage performance. A network of orderly flakes also provides the wide-open spaces for easy access to electrolyte ions and permits rapid electron transport. Battery-type redox behavior has been observed for the hydrothermally prepared CMO-12 h composite in an aqueous electrolyte with a high storage property of 503 C g⁻¹ at a specific current of 2 A g⁻¹. Asymmetric supercapacitors using the CMO-12 h composite owns the excellent specific capacitance value of 198 F g⁻¹ at a specific current of 2 A g⁻¹. Furthermore, the device demonstrates extended cyclic stability of 85.6% capacitance retention after 5000 cycles.