Effect of Electrodeposition Time on Capacitive Behaviour of Graphene-Zinc Oxide

Graphene–ZnO composite thin film was synthesized using Hummer method and prepared using electrodeposition has good potential for supercapacitors applications. However, times of electrodeposition could influence the capacitive behaviour due to concentration of graphene layer. The cyclic-voltametric, CV and impedance spectroscopy, EIS showed significant data on these studies. Five samples with concentration of graphene from 1 mg/ml to 5 mg/ml was prepared, represent from 0.04, 0.08, 0.12, 0.16 and 0.20 g mass of graphene. Deposition time was selected to 20, 40 and 60 minutes at 5V of fixed deposition voltage. Despite cyclic voltammetry, these five sample also was measured on their conductivity. CV characterizations of GZ4-20 shows the best result in CV curve shape with complete charging discharging process at 2.88E-05 Fg -1 for specific capacitance at 20 minutes. The EIS characterization of GZ5-40 shows series resistance at 523.220 Ω as the best result in EIS characterization for 40 minutes electrodeposition time. Deposition time of Graphene-Zinc Oxide at 40 minutes prove that the time can influence on electrocatalytic performance. However, it can be good candidate for various micro electrical of capacitor devices.