@article {175, title = {Solubility of Gases in Water Confined in Nanoporous Materials: ZSM-5, MCM-41, and MIL-100}, journal = {The Journal of Physical Chemistry C}, volume = {119}, year = {2015}, month = {Sep-17-2015}, pages = {21547 - 21554}, abstract = {
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Oversolubility, which corresponds to large apparent gas solubilities in liquids confined in nanoporous solids, has been proposed as a means to develop novel adsorption, phase separation, or catalytic processes. We report a molecular simulation study to help design such hybrid adsorbents consisting of a solvent confined in host nanoporous materials. Water is selected as the confined solvent because of its ubiquity in industrial applications, while N2, CH4, and CO2 are selected as they allow probing the effect of specific molecular interaction and polarity. For each system, we consider a zeolite, an ordered mesoporous silica, and a metal\–organic framework as the confining host as they present different morphologies, porosities, and surface chemistries. We show that oversolubility is always observed because the apparent solubility in these materials surpasses the bulk solubility. In all cases, oversolubility is an enhanced bulklike solubility in which solubility is favored in the regions of low water density formed by the layering of the solvent. Such an oversolubility mechanism, which arises from the fact that the gas\–solid interactions are weaker than the solvent\–solid interactions, leads to large uptakes as high as a few hundred times that expected from bulk solubility.

}, issn = {1932-7447}, doi = {10.1021/acs.jpcc.5b06660}, author = {Linh Ngoc Ho and Schuurman, Yves and David Farrusseng and Benoit A. Coasne} } @article {91, title = {Role of Silver Nanoparticles in Enhanced Xenon Adsorption Using Silver-Loaded Zeolites}, journal = {Journal of Physical Chemistry C }, volume = {118}, year = {2014}, month = {Oct-06-2014}, pages = {25032-25040}, type = {Article}}, abstract = {
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Molecular simulation is used to unravel the adsorption mechanisms of xenon on Ag-doped ZSM-5 zeolite. We show that silver nanoparticles, which form at the external surface of zeolite crystallites, are responsible for enhanced xenon physisorption at very low pressure. We also propose a simple model of adsorption on such composite materials made up of silver-exchanged zeolites and silver nanoparticles adsorbed at the zeolite surface. This model, which allows predicting the adsorption of other gases without any additional parameters, provides a tool to characterize the amount of reduced silver as well as the silver particle size distribution (in good agreement with transmission electron microscopy images). The presence of a majority of silver nanoparticles is further characterized by means of X-ray diffraction and X-ray Absorption Spectroscopy at the silver K edge.

}, issn = {1932-7447}, doi = {10.1021/jp507590a}, author = {Deliere, Ludovic and Topin, Sylvain and Benoit A. Coasne and Fontaine, Jean-Pierre and De Vito, Sophie and Den Auwer, Christophe and Solari, Pier Lorenzo and Daniel, Cecile and Schuurman, Yves and David Farrusseng} } @article {33, title = {Gas uptake in solvents confined in mesopores: adsorption versus enhanced solubility}, journal = {The Journal of Physical Chemistry Letters}, volume = {4}, year = {2013}, month = {Jun-25-2013}, pages = {2274{\textendash}2278}, abstract = {
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Three molecular mechanisms for gas uptake in a solvent confined in mesopores are identified. On the one hand, CO2 uptake is an adsorption-driven phenomenon that arises from the strong interaction between the gas molecules and the pore surface. On the other hand, H2 uptake is a confinement-induced enhanced solubility in which solubility is favored in the regions of low solvent density formed by the layering of the solvent. In partially filled pores, adsorption at the gas/liquid solvent interface is a third mechanism that leads to large gas uptakes. This study, which sheds light on previously reported yet unclear oversolubility in pores, provides a guide to design hybrid porous catalysts consisting of a solvent confined in a porous solid.

}, doi = {10.1021/jz401143x}, author = {Linh Ngoc Ho and St{\'e}phanie Clauzier and Schuurman, Yves and David Farrusseng and Benoit A. Coasne} }