碳化温度对MOFs基碳材料吸附性能的影响

本文以均苯三酸和二水合醋酸锌、苯并咪唑/苯并三氮唑作为反应物,在50℃条件下合成了两种金属有机框架结构MOFs-Bm/MOFs-Bt。分别在不同温度下氮气氛围中煅烧得到纳米多孔碳材料Bm-t/Bt-t。利用红外光谱仪、同步热分析仪对配合物的结构以及热稳定性进行了表征;对煅烧后样品采用场发射扫描电子显微镜、比表面及孔径分析仪等进行表征,并通过对亚甲基蓝的脱除来测试其吸附性能。结果表明:煅烧温度越高碳材料对亚甲基蓝的吸附性越好;相同煅烧温度下Bm-t比Bt-t具有更好的吸附效果;煅烧温度在600℃-750℃间吸附速率发生了断崖式变化,说明虽然根据热重分析,600℃时配合物的框架结构完全坍塌,但并未碳化完全。

Effect of carbonization temperature on MOFs-carbon adsorption performance

In this paper,two metal organic frameworks MOFs-Bm and MOFs-Bt were synthesized by using trimesic acid and zinc acetate dihydrate as raw materials with 2-methylbenzimidazole or benzotriazole as the second ligands at 50℃.The two complex were calcined at different calcination temperatures in a nitrogen atmosphere to obtain nanoporous carbon materials Bm-t and Bt-t.The structure and thermal stability of the complexes were characterized by IR and TG.The calcined samples were characterized by FESEM,BET,etc.,and their adsorption properties were tested by removal of methylene blue.The results show that the higher the calcination temperature,the better the adsorption of carbon materials to methylene blue.Bm-t has better adsorption effect than Bt-t at the same calcination temperature.The calcination temperature has a cliff-like change between 600℃and 750℃,which notes that although the frame structure of the complex completely collapses according to the thermogravimetric analysis at 600℃,it is not completely carbonized at this temperature.