Graphene oxide hybrid with sulphur-nitrogen polymer for high-performance pseudocapacitors.

Towards the introduction of fast faradaic pseudocapacitive behavior and the increase of the specific capacitance of carbon-based electrodes, we have covalently functionalized graphene oxide with a redox active thiourea-formaldehyde polymer yield-ing a multifunctional hybrid system. The multiscale physical and chemical characterization of the novel 3-dimensional hy-brid revealed high material's porosity with high specific surface area (402 m2 g-1) and homogeneous element distribution. The presence of multiple functional groups comprising sulphur, nitrogen and oxygen, provide additional contribution of Faradic redox reaction in supercapacity performance, leading to a high effective electrochemical pseudocapacitance. Signifi-cantly, our graphene-based 3-dimensional thiourea-formaldehyde hybrid (G3DTF) exhibited specific capacitance as high as 400 F g-1, areal capacitance of 160 mF cm-2 and an energy density of 11.1 mWh cm-3 at scan rate of 1 mV s-1 with great capacitance retention (100%) after 5000 cycles at scan rate of 100 mV s-1.