| Environmental and energy issues compel humanity to seek new, efficient and environmentally friendly energy storage and conversion devices. Supercapacitors（SCs） have fast charge-discharge rate, high power performance and long life（> 105 cycles）, that it received much attention. Carbon-based material with low cost, good stability is one of the most promising electrode materials. The improvement of the conductivity and increase of the specific surface area can enhance the electron transport capacity and storage capacity electrolyte ions, thus improving the storage performance of the materials. Considering the good electrical conductivity of graphene and the large specific surface of porous carbon, the graphene oxide were selected as a precursor of graphene, and induced the growth of biomass（glucose, gelatin） based on group interaction principles to obtain a porous carbon/ graphene two-dimensional composite. The materials have shown the significantly enhanced the energy storage characteristics. The main contents are as follows:1. The two-dimensional porous carbon/RGO composite carbon material（PCGS） was constructed by using glucose as carbon source, graphite oxide as sheet inducing agent, through a hydrothermal-carbonization-activation（ZnCl2 as the activator, N2 condition） method. By changing the amount of glucose, the thickness of the two-dimensional sheet material and specific surface area can be effectively regulated. Under suitable conditions the specific surface area of materials can up to 3200 m2 g-1. At the current density of 1 Ag-1, it show higher capacitance value 232 F g-1, good rate performance and coulombic efficiency. The results indicated reasonable and effective combination of RGO and the porous carbon material can improve the capacitor performance and cycle stability.2. In this part, the gelatin was used as carbon source and graphite oxide as structure-directing agent for the induction of gelatin assembly.the LPCG based materials with a thickness about 100 nm and high specific surface area(up to 1476 m2 g-1) through the carbonization and activation process. The rGO not only improves the conductivity LPCG base material, but is also important to induce the formation of a thin layer of carbon having a layered structure. The thickness of the carbon derived from gelatin is about 500 nm in the case of the absence of RGO. The results indicated an increase in electrical conductivity properties of the materials will help to improve rate performance. The jointed action of good conductivity and large specific surface area are helpful to obtain the high energy storage properties. Under optimum conditions, LPCG materials exhibited a high specific capacitance(at 0.5 A g-1, 455 F g-1; at 1 A g-1, 366 F g-1), excellent rate properties(at 30 A g-1, 221 F g-1) and a good cycle stability.3. By introducing a carbon nanotube with good conductivity, the voltage window of the materials can be further expand, thus improve the storage properties of LPCG material. By using the gelatin as carbon source, CNTs as conductive agent, graphite oxide sheets as inducer, the ternary porous carbon-based materials（LPC-C-G） could be obained by carbonization-activation route. The material processes the high specific surface area up to 1791 m2 g-1. In this composite material, graphene can induce the formation of sheet material, porous carbon in favor of electrolyte ions access and diffusion, CNTs can improve the conductivity of the material. As a result, the material exhibits a broad voltage window（1.1V）, high specific capacitance(at 2 A g-1, 313 F g-1) and excellent cycle stability（> 86%, 5000 cycles）. Experimental results showed that the improvement of the electrical conductivity of materials will help to improve the rate performance and broaden the voltage window. In aqueous electrolytes, the energy density can reach to 10.28 W h kg-1 at low power density 500 W kg-1.
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