Study on the electrochemical performance of Ni-doped ZnO nanorods utilized for the high-performance supercapacitor application

The nickel-doped ZnO nanorods have been synthesized through a simple precipitation method. The final product was further characterized through XRD, SEM, HRTEM, FTIR, and electrochemical analysis. The XRD spectrum illustrates ZnO and Ni:ZnO samples show the hexagonal structure. The surface morphology shows the rod-shaped ZnO, and the rods are elongated while addition of Ni. The functional group composition of prepared samples shows the purity of the prepared nanomaterials. The electrochemical performance of the prepared ZnO, 2%Ni:ZnO, and 4%Ni:ZnO shows higher capacitance value through the CV curve is 214, 345, and 276 F/g at 10 mV/s and through the GCD curve 184, 205, and 125 F/g for 4%Ni:ZnO, 2%Ni:ZnO, and ZnO electrodes; also, these electrodes show a maximum energy value of 18.63, 20.75, and 12.65 Wh/kg, and related power density values are 1390, 1465, and 1340 W/kg, respectively. Moreover, while adding the Ni content in ZnO, the cyclic stability was highly increased up to 98%. Also, the Ni:ZnO electrode shows much higher capacitance and lower Rct values than the pure ZnO electrode. The synergistic effect of Ni in ZnO indicates the higher capacitance.