煤液化沥青基多孔炭的制备及电化学性能研究

Preparation and Electrochemical Properties Study of Porous Carbon that Based on Coal Liquefaction Asphalt

以煤液化沥青为炭源,以3种不同形态的SiO_2(正硅酸四乙酯、硅溶胶、纳米SiO_2)为模板,制备多孔炭,通过模板与煤液化沥青的投料比,调整多孔炭的表面结构。采用SEM、N2吸附-脱附、电化学工作站对多孔炭的微观结构和电化学性能进行了研究。结果表明:模板的类型决定多孔炭材料的孔径分布,以正硅酸四乙酯为模板的多孔炭的平均孔径为2~3nm,以硅溶胶为模板的多孔炭的平均孔径为7.8nm,以纳米SiO_2为模板的多孔炭的平均孔径为12nm。以正硅酸四乙酯为模板时,当SiO_2与煤液化沥青的投料为0.6时,多孔炭的总孔容最大,0.605cm^3/g,比表面积为789m^2/g,且表现出较好的电化学性能,在2000mA/g的电流密度下,比电容为71F/g。

Porous Carbons(PCs)were prepared from coal liquefaction asphacltors(CLA)derived from coal liq.uefaction residue with three different kinds of SiO2(tetraethoxysilane,ludox,silia nanoparticles)as template.The microstructure and electrochemical properties of PCs were investigated with SEM,N2 adsoption-desorp.tion,and electrochemical workstation.The results show that pore diameter distribution of PCs were depended on the shape of template.The average pore diameter of PCs with tetraethoxysilane were 2-3nm,average pore diameter of PCs with ludox were 7.8 nm,average pore diameter of PCs with silia nanoparticles were 12nm.The highest total pore volume of PCs is 0.605 cm3/g.With tetraethoxysilane as template of SiO2/CLA ratio 0.6,and the specific surface area is 789 m2/g,while the specific capacitance of the PC is 71F.g-1 at a current density of 2000 mA.g-1.