Adsorption-induced deformation of mesoporous solids.
نویسندگان
چکیده
The Derjaguin-Broekhoff-de Boer theory of capillary condensation is employed to describe deformation of mesoporous solids in the course of adsorption-desorption hysteretic cycles. We suggest a thermodynamic model, which relates the mechanical stress induced by the adsorbed phase to the adsorption isotherm. Analytical expressions are derived for the dependence of the solvation pressure on the vapor pressure. The proposed method provides a description of nonmonotonic hysteretic deformation during capillary condensation without invoking any adjustable parameters. The method is showcased drawing on the examples of literature experimental data on adsorption deformation of porous glass and SBA-15 silica.
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ورودعنوان ژورنال:
- Langmuir : the ACS journal of surfaces and colloids
دوره 26 16 شماره
صفحات -
تاریخ انتشار 2010