Microwave-assisted synthesis of gadolinium/cerium oxide nanocomposite for high-performance supercapacitor

In the present study, the nanocomposite of gadolinium/cerium oxide was synthesized via a simple and quick microwave-assisted method for supercapacitor application. The different percentages of gadolinium (Gd) were added to cerium oxide (CeO₂) to study the effect of the addition of Gd on the electrochemical performance of the CeO₂. The crystallographic and morphological study were conducted through different characterization techniques. The electrochemical performance of these formed nanocomposites was tested using cyclic voltammetry and galvanostatic charge–discharge techniques and a maximum specific capacitance of 396 Fg⁻¹ was obtained for a 20%-mixed Gd sample at 1 Ag⁻¹ current density. Further asymmetric supercapacitor device was fabricated 20-Gd/CeO₂/C//AC/C using PVA/KOH gel electrolyte which demonstrated an energy density of 23 Whkg⁻¹ at a power density of 1379 Wkg⁻¹. The cyclic performance was measured for fabricated devices and was found that 91% capacitance retention after 2000 cycles.