Pressure induced liquid infiltration in nanopores

In this article, we report the results of an infiltration∕defiltration experiment of a hydrophobic nanoporous silica gel. As the pressure is increased to the critical value, water can be forced into the nanopores. When the pressure is reduced, however, the “outflow” is difficult, leading to a significant hysteresis of sorption isotherm. A first-order thermodynamics analysis is performed to capture the confinement effect of nanopore walls and the mass and energy exchanges between liquid and gas phases in nanopores.