Structural, Optical and Electrochemical Properties of Sn-doped ZnO Nanoparticles: Effect of Doping Concentration

Chemically prepared tin-doped zinc oxide (Sn-doped ZnO) nanoparticles are prepared with different doping concentrations of tin. The crystallite size, strain, and texture coefficients are examined. The addition of tin reduces the crystallite size and enhances the dislocation density of the material. The optical bandgap of tin-doped nanoparticles is lower than undoped nanoparticles. The UV emission, near band edge emission and zinc vacancies are observed in the luminescence spectrum. The prepared nanoparticles are used as the electrode material in the supercapacitors. The cyclic voltammetry and galvanostatic charge-discharge techniques are employed to examine the specific capacitance of the material. The specific capacitance is notably enhanced due to the doping of tin. The capacitive and diffusive current contributions are evaluated and the doping enhances the capacitive current contribution. The prepared tin-doped electrode material is an excellent candidate for supercapacitor applications.