Synthesis and characterization of Sr-doped CdO nanoplatelets for supercapacitor applications

Undoped and Sr-doped CdO  nanoplatelets were efficiently synthesized via simple co-precipitation method. The prepared materials were characterized using X-ray diffraction (XRD) and Scanning electron microscope (SEM). XRD pattern confirms the synthesized nanomaterial was phase pure Sr-doped CdO. SEM images reveal the formation of nanoplatelets like morphology. Electrochemical supercapacitor characterization of CdO and Sr-doped CdO nanoplatelets were done using cyclic voltammetry, Galvanostatic charge–discharge, and Electrochemical impedance spectroscopy measurements. The estimated specific capacitance value for Sr-doped CdO and CdO at a current density of 1 Ag⁻¹ was 752 and 250 Fg⁻¹. The Sr-doped CdO nanoplatelets exhibits about three times higher specific capacitance than the pure CdO electrode material. Sr-doped CdO electrode retains 93% of initial specific capacitance after 2000 charge–discharge cycles whereas CdO retains only 85%. The solution resistance (R_s) value of Sr-doped CdO (2.95 Ω) is lower than the CdO (3.57 Ω). This high specific capacitance, long cycle life and low charge transfer resistance confirms the suitability of Sr-doped CdO nanoplatelets for supercapacitor applications.