Graphene-based Thin Film Supercapacitor with Graphene Oxide as Dielectric Spacer

Thin film supercapacitors are produced by using electrochemically exfoliated graphene (G) and wet-chemically produced graphene oxide (GO). Either G/GO/G stacked film or sole GO film are sandwiched by two Au films to make devices, where GO is the dielectric spacer. The addition of graphene film for charge storage can increase the capacitance about two times, compared to the simple Au electrode. It is found that the GO film has very high dielectric constant, accounting for the high capacitance of these devices. AC measurements reveal that the relative permittivity of GO is in the order of 10 within the frequency range of 0.1–70 Hz. a) Author to whom correspondence should be addresses. E-mail: [email protected]