文献类型：期刊文献

英文题名：Development of a density functional theory in three-dimensional nanoconfined space: H2 Storage in metal-organic frameworks

作者：Liu, Yu[1,2]; Liu, Honglai[2]; Hu, Ying[2]; Jiang, Jianwen[1]

机构：[1] Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576, Singapore; [2] State Key Laboratory of Chemical Engineering, Department of Chemistry, East China University of Science and Technology, Shanghai 200237, China

年份：2009

卷号：113

期号：36

起止页码：12326

外文期刊名：Journal of Physical Chemistry B

收录：EI(收录号：20093812316028)

语种：英文

外文关键词：Crystalline materials - Free energy - Organic polymers - Organometallics - Adsorption - Intelligent systems - Monte Carlo methods

摘要：A density functional theory (DFT) is developed in three-dimensional nanoconfined space and applied for H2 storage in metal-organic frameworks. Two different weighting functions based on the weighted density approximation (WDA) are adopted, respectively, for the repulsive and attractive contributions to the excess free energy. The Carnahan-Starling equation and a modified Benedicit-Webb-Rubin equation are used to calculate the excess free energy of uniform fluid. To compare with DFT predictions, grand canonical Monte Carlo simulations are carried out separately. For H2 adsorption in MOF-5 and ZIF-8, the isotherms predicted from the DFT agree well with simulation and experiment results, and the DFT is found to be superior to the mean-field-approximation (MFA)-based theory. The adsorption energies and isosteric heats predicted are also in accord with simulation results. From the predicted density contours, the DFT shows that the preferential adsorption sites are the corners of metal clusters in MOF-5 and the top of organic linkers in ZIF-8, consistent with simulation and experimental observations. ? 2009 American Chemical Society.