模板法煤沥青基中孔炭的制备及其电化学性能

摘要

以煤沥青质为碳源,气相法二氧化硅为模板,制备中孔炭(Mesoporous carbon,MC),通过CO2活化调变其表面结构.用TEM、N2吸附、电化学工作站及Land电池测试系统等对产品炭的微观结构及电化学性能进行研究.结果表明:在活化温度900℃、CO2气流量100mL/min条件下,随着活化时间的增加,炭产品的BET比表面积、微孔孔容均呈增加趋势.在活化时间为150min时,产品炭的BET比表面积可达1 360m2/g,比活化前的比表面积提高了约88%.产品炭作为超级电容器电极材料表现出良好的电化学性能,活化时间为120min的样品,在1000mA/g的电流密度下,材料的质量比电容为135F/g,10000次充放电循环后,比电容值保持率高达93%.%Mesoporous carbons ( MCs) were made from coal pitch derived from coal liquefaction residue with silica nanoparticles as template and CO2 as activation agent. The microstructure and electrochemical properties of the MCs were investigated with TEM, N2 adsorption, an electrochemical workstation and a Land battery test system. Results show that the specific surface area increases with activation time at 900 ℃ under a CO2 flow rate of 100 mL·min-1. The specific surface area of MC activated for 150min is 1360 m2·g-1 while that of the un-activated one is 722 m2·g-1. The specific capacitance of the MC activated for 150 min is 135 F·g-1 at a current density of 1 000 mA·g-1 and the decrease in its specific capacitance is 7％ after being charged and discharged 10000 times.