@article {181, title = {Predicting Adsorption on Bare and Modified Silica Surfaces}, journal = {The Journal of Physical Chemistry C}, volume = {119}, year = {2015}, month = {Mar-19-2015}, pages = {6009 - 6017}, abstract = {
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We show that Derjaguin\’s theory of adsorption can be used to predict adsorption on bare and modified surfaces using parameters available to simple experiments. Using experiment and molecular simulation of adsorption of various gases on hydroxylated, methylated, and trifluoromethylated silica, this simple parametrization of Derjaguin\’s model allows predicting adsorption on any functionalized surface using a minimum set of parameters such as the heat of vaporization of the adsorbate and the Henry constant of the adsorption isotherm. This general yet simple scheme constitutes a powerful tool as it avoids having to carry out tedious and complex adsorption measurements.

}, issn = {1932-7447}, doi = {10.1021/jp511726a}, author = {L{\'e}pinay, Matthieu and Broussous, Lucile and Licitra, Christophe and Bertin, Fran{\c c}ois and Rouessac, Vincent and Ayral, Andre and Benoit A. Coasne} } @article {174, title = {Probing the microporosity of low-k organosilica films: MP and t-plot methods applied to ellipsometric porosimetry data}, journal = {Microporous and Mesoporous Materials}, volume = {217}, year = {2015}, month = {Nov-15-2015}, pages = {119 - 124}, abstract = {

Ellipsometric porosimetry (EP) experiments are performed to obtain the adsorption isotherms of water, methanol, and toluene on pristine and damaged SiOCH porous materials. The use of gaseous adsorbates with different polarities, sizes, and surface tensions enables us to probe their affinity with such organosilica surfaces. Using reference t-curves obtained from Statistical Mechanics molecular simulations, we discuss the ability of the MicroPore analysis (MP) method to accurately estimate micropore sizes from EP measurements by comparing them with the mean pore sizes obtained using positron annihilation lifetime spectroscopy (PALS) and grazing incidence small angle X-ray scattering (GISAXS). We also report accessible microporous volumes estimated from the t-plot method used with the reference t-curves obtained by means of molecular simulation. We show that EP characterization of microporous films combined with the MP and t-plot methods can be improved by taking into account the effect of the chemical nature of the pore surface on the variation of the adsorbed thickness (t-curve).

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}, issn = {13871811}, doi = {10.1016/j.micromeso.2015.05.050}, author = {L{\'e}pinay, Matthieu and Broussous, Lucile and Licitra, Christophe and Bertin, Fran{\c c}ois and Rouessac, Vincent and Ayral, Andre and Benoit A. Coasne} }