文献类型：期刊文献

英文题名：Water Adsorption in Metal-Organic Frameworks with Open-Metal Sites

作者：Peng, Xuan[1,2];Lin, Li-Chiang[2];Sun, Weizhen[2,3,4];Smit, Berend[2,5,6]

机构：[1]Beijing Univ Chem Technol, Dept Automat, Coll Informat Sci & Technol, Beijing 100029, Peoples R China;[2]Univ Calif Berkeley, Dept Chem & Biomol Engn, Berkeley, CA 94720 USA;[3]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[4]E China Univ Sci & Technol, Key Lab Adv Control & Optimizat Chem Proc, Shanghai 200237, Peoples R China;[5]Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA;[6]Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA

年份：2015

卷号：61

期号：2

起止页码：677

外文期刊名：AICHE JOURNAL

收录：;EI(收录号：20145200381772);WOS:【SCI-EXPANDED(收录号:WOS:000348033200025)】；

基金：XP was supported by the Open Project of State Key Laboratory of Chemical Engineering (SKL-Che-12C01). XP and WZS were supported by the China Scholarship Council. LCL and BS were supported as part of the Center for Gas Separations Relevant to Clean Energy Technologies, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001015.

语种：英文

外文关键词：adsorption; molecular simulation; water; metal; organic frameworks

摘要：H2O adsorptions inside porous materials, including silica zeolites, zeolite imidazolate frameworks, and metal-organic frameworks (MOFs) using molecular simulations with different water models are investigated. Due to the existence of coordinately unsaturated metal sites, the predicted adsorption properties in M-MOF-74 (M=Mg, Ni, Co, Zn) and Cu-BTC are found to be greatly sensitive to the adopted H2O models. Surprisingly, the analysis of the orientations of H2O minimum energy configuration in these materials show that three-site H2O models predict an unusual perpendicular angle of H2O plane with respect to the Metal-O-4 plane, whereas those models with more than three sites give a more parallel angle that is in better agreement with the one obtained from density functional theory (DFT) calculations. In addition, the use of these commonly used models estimates the binding energies with the values lower than the ones computed by DFT ranging from 15 to 40%. To correct adsorption energies, simple approach to adjust metal-O(H2O) sigma parameters to reproduce the DFT-calculated binding energies is used. With the refined parameters, the computed water isotherms inside Mg-MOF-74 and Cu-BTC are in reasonable agreement with experimental data, and provide significant improvement compared to the predictions made by the original models. Further, a detailed inspection on the water configurations at higher-pressure region was also made, and observed that there is an interesting two-layer water network formed using three- and four-site models. (c) 2014 American Institute of Chemical Engineers AIChE J, 61: 677-687, 2015