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Graphene-based porous materials have attracted broad attentions in supercapacitor (SC) applications, due to the high conductivity and large surface area. The most widely used approach to fabricate graphene-based porous electrode materials is the reduction of graphene oxide (GO). The reduction process significantly affects the properties of reduced graphene oxide (RGO), including the conductivity, surface chemistry and the porosity. Therefore, the control the reduction process is of great importance to produce high performance electrode materials. In this paper, we explore the control of the electrical conductivity and surface chemistry of flash reduced GO material, which depends on the reduction degree. The reduction degree is tuned by varying the energy of a camera flash used to reduce the GO. The reduction degree is characterized by X-ray photoelectron spectroscopy (XPS). We find the high reduction degree (low oxygen content) is beneficial to achieve high electrical conductivity, however, the overall specific capacitance becomes lower. As a result, we can see that electrode surface chemistry is more dominant than its electrical conductivity in enhancing SC specific capacitance.
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