沸石咪唑骨架N2吸附的分子模拟与BET分析  

Molecular simulation of N_2 adsorption in zeolitic imidazolate frameworks and their BET analysis

作　　者：郭海超[1] 朱志敏[1] 马正飞[1] 刘晓勤[1] 

机构地区：[1]南京工业大学化学化工学院,材料化学工程国家重点实验室,江苏南京210009

出　　处：《南京工业大学学报（自然科学版）》2011年第6期35-40,76,共7页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：江苏省高校自然科学重大基础研究项目(08KJA530001)

摘　　要：采用分子模拟的方法模拟77 K下N2在沸石咪唑骨架材料(ZIFs)上的吸附等温线,并与实验结果比较,确定合适的力场参数,提供用BET方法分析ZIFs材料比表面积的吸附等温线。通过BET吸附方程中的参数c与单层吸附压力(p/p0)m之间的关系为(p/p0)m=(槡c+1)-1,确定应用BET方程分析时的压力区间。采用这样的方法计算5种ZIF材料的比表面积并与根据一致性原则(Rouquerol,2007)的结果进行比较,结果表明方法是可靠的,这说明采用合适的压力区间时,BET方法同样适用于分析微孔ZIF材料的比表面积。计算得到的5种ZIF材料比表面积均在1 000 m2/g以上,说明ZIF材料是一种具有高比表面积、有应用前景的吸附材料。Adsorption isotherms of N2 in five microporous zeolitic imidazolate frameworks（ZIFs） at 77 K for BET surface area analysis were simulated by molecular simulation.Suitable force field parameters were validated compared with the experimental data.The relationship between parameter c and the relative pressure corresponding to the monolayer capacity（p/p0）m of BET equation（p/p0）m=（c＋1）-1 could be used to determine the suitable pressure range for surface area analysis.With the method,the BET surface areas of five ZIFs were estimated and compared with the data obtained from the consistency criteria（Rouquerol,2007）.The results demonstrated that the method for the suitable pressure range determination could be used to analyze microporous ZIFs surface area by BET equation.The calculated surface areas of five ZIFs were more than 1 000 m2/g,thus indicating that ZIF materials are a kind of potential adsorbent material with high surface area.

关 键 词：沸石咪唑骨架 吸附 巨正则Monte CARLO模拟 BET 

分 类 号：O641[理学—物理化学] O647[理学—化学]