MCM-41介孔碳材料的合成及其电化学性能研究

Synthesis of MCM - 41 of Mesoporous Carbon Materials and Electrochemical Performance

摘要:

该文以十六烷基三甲基溴化铵（CTAB）为模板剂,可溶性淀粉(Starch)为碳源，通过软模板法一步合成了高度有序的介孔碳材料。通过热重分析（TG）、X-射线衍射（XRD）、N2吸附-脱附和透射电子显微镜（TEM）等对材料的结构进行了表征。结果表明：当模板剂与可溶性淀粉质量比为m(CTAB):m(Starch)=1.0：1.5，650 ℃焙烧碳化3 h，并用氢氟酸去除二氧化硅后，所得到的MCM-41有序介孔碳材料（OMC-650）的比表面积为985 m2/g，平均孔径为孔径分布均匀，平均孔径为2.5 nm。XRD和TEM分析表明，OMC-650具有典型的MCM-41结构特征，有序性良好。以OMC-650作为工作电极，氧化汞为参比电极，铂为辅助电极，用6 M•L-1 KOH做电解液，测其比电容为150 F/g，且经过1000次循环后，其比电容仍为138 F/g，为原电容的92%，说明所合成的材料具有良好的电容稳定性。

Abstract:

In this paper, a highly ordered mesoporous carbon material was synthesized by a soft template method with sixteen alkyl three methyl ammonium bromide (CTAB) as the template and soluble starch (Starch) as the carbon source. The structures of ordered mesoporous carbon were characterized by thermal gravimetric analysis (TG), X-ray diffraction (XRD), N2 adsorption desorption and transmission electron microscopy (TEM). The results show that MCM-41 ordered mesoporous carbon materials was got when the mass ratio of template and soluble starch was 1 to 1.5, carbonized for 3 h at 650 oC and removing the silica with hydrofluoric acid . The BET surface area of MCM-41 mesoporous porous carbon materials (OMC-650) was 985 m2/g with uniform and abundant mesoporous structure with pore size (2.5 nm). XRD and TEM analysis show that OMC-650 has typical MCM-41 structure with good order. These merits lead to a big specific capacitance (150 F•g-1) using OMC-650 as work electrode materials , mercuric oxide as reference electrode and platinum as auxiliary electrode with 6 mol.L-1 KOH as the electrolyte. After 1000 cycles, the specific capacitance of OMC-650 is 138 F/g with capacitance retention of 92 % and an excellent cycling stability in 6 mol•L-1 KOH aqueous electrolytes.