Thin Film Investigation of Silver Doped Zinc Oxide as Electrode Material (Published)
Thin film materials for the production of low energy density devices such as supercacitors are very attractive because of the positive impact on the environment. Metal oxides thin films materials are widely used due to their unique properties unlike single structured metal oxide thin films which amy suffer from low efficiency under visible light. In this study the doping of ZnO thin films with Ag form a composite material with new properties due to synergetic effect. The synthesis of ZnO thin film was by electrodeposition technique after which the optical properties were characterized using UV-VIS spectrometer. A slight shift in the absorption spectra to the higher wave length was observed in all the samples. It can be seen that the optical transmission of pure ZnO is about 47 % at 1026 nm in the visible region and after doping it increased to 71 % at 950 nm due to the presence of impurity; negative reflectance spectra shown by most samples is an indication of the incident and refracted wave travelling in the same direction. The optical energy gap of the doped samples ranges from 3.32-3.43 eV, these observations show that the Ag behavior as a p-type dopant of ZnO is good for the realization of low energy density devices such as supercapacitors.
Cisssan Sylvanus (2022) Thin Film Investigation of Silver Doped Zinc Oxide as Electrode Material, European Journal of Material Science, 9, (1), 44-63
Keywords: Electrode, Material, Thin Film, oxide, silver doped zinc
Structural and electrochemical properties of agxsno1-x/g (0.3≤x≤0.4) composite electrodes. (Published)
The electrochemical performance of AgxSnO1-x/G composite (0.3 ≤ x ≤0.4) as an electrode material was investigated for supercapacitor application. The reduce graphene oxide (G) was synthesized using an improved modified Hummer’s method and the composites electrode material was synthesized with a hydrothermal reduction method. The introduction of AgxSnO1-x (0.3 ) material into the network of the reduce graphene oxide enhances the kinetic for both charge transfer and ion transport throughout the composite electrode. The composite was characterized by Raman, SEM and XRD which reveals the morphology and structural properties. The Electrochemical properties were investigated using cyclic voltammetry and electrochemical impedance spectroscopy analysis. The electrode AgxSnO1-x (x = 0.4) gives the specific capacitance of 123.1 F/g, energy density of 30.9 Wh/kg, and power density of 541.1 W/kg after one cycle. After 1000 cycles CV test, it gives the capacitance efficiency of 95.4 % capacitance retention. The composites showed greatly improved cycling stability and demonstrated positive synergistic effect between AgxSnO1-x (0.3 ) material and the reduce graphene oxide as composite electrode to meet the requirement for high energy and power density.
Keywords: Composite, Electrode, Supercapacitance