基于钴离子交换分子筛为模板的三维有序微孔炭低温合成及其宏量制备

Large-scale synthesis of 3D ordered microporous carbon at low temperature using cobalt ions exchanged zeolite Y as a template

沸石模板炭(ZTCs)由于具有独特的三维有序微孔结构和高比表面积,在吸附和能量存储等方面表现出诸多优异的性能。然而,ZTCs有效合成方法的缺乏和大规模合成的困难严重限制其发展。本文通过使用钴离子交换的Y型沸石分子筛作为模板,采用直接乙炔化学气相沉积(CVD)的方法,开发出一种低温CVD合成及宏量制备ZTCs的简单工艺路线。沸石中的钴离子作为Lewis酸位点,通过d-π配位效应催化乙炔在400℃低温热解,使碳沉积选择性地发生在沸石内部。通过对CVD温度和时间的优化,ZTC_((Co))-400-8h具有优异的三维有序微孔结构、高比表面积(3000 m^(2) g^(-1))、大的孔体积(1.33 cm^(3) g^(-1)),CO_(2)吸附容量和选择性分别为2.78 mmol g^(-1)(25℃,100 kPa)和98。本工作中,利用简单的合成方法实现了高质量ZTCs的宏量制备,使用10.0 g/批次沸石模板制备的ZTC_((Co))-400-8h(L)的比表面和孔体积可达到2700 m^(2) g^(-1)和1.27 cm^(3) g^(-1)。

Zeolite-templated carbons(ZTCs)have a unique three-dimensional(3D)ordered microporous structure and an extralarge surface area,and have excellent properties in adsorption and energy storage.Unfortunately,the lack of efficient synthesis strategies and the difficulty of doing this on a large-scale have seriously limited their development.We have developed a large-scale simple production route using a relatively low synthesis temperature and direct acetylene chemical vapor deposition(CVD)using Co ion-exchanged zeolite Y(CoY)as the template.The Co^(2+)confined in the zeolite acts as Lewis acid sites to catalyze the pyrolysis of acetylene through the d-πcoordination effect,making carbon deposition occur selectively inside the zeolite at 400℃ rather than on the external surface.By systematically investigating the CVD temperature and time,the optimum conditions of 8 h deposition at 400℃ produces an excellent 3D ordered-microporous structure and outstanding structure parameters(3000 m^(2) g^(-1),1.33 cm^(3) g^(-1)).Its CO_(2) adsorption capacity and selectivity are 2.78 mmol g^(-1)(25℃,100 kPa)and 98,respectively.This simple CVD process allows the synthesis of high-quality ZTCs on a large scale at a low cost.