Preparation and characterization of mesoporous silica–polyvinyl butyral hybrid coatings by electrophoretic deposition

Abstract

Abstract Thick mesoporous silica (MPS) films with sufficient mechanical strength and high porosity were prepared on aluminum plates by using electrophoretic deposition (EPD) with the addition of a small amount of polyvinylbutyral (PVB, 3.5–8.0 wt%) as binder. The porosity of the MPS films was approximately 50 vol%. The film thickness could be controlled by the deposition conditions, and a thickness of ca. 50 μm is reasonable for effectively using the whole MPS film. These MPS films exhibited good water vapor adsorption-desorption properties and sufficient stability for more than 150 adsorption-desorption cycles. When used in dehumidification applications, these MPS films had a dehumidification rate of 6.3 g-H2O/g-MPS per hour, with an adsorption-desorption cycle as short as 2 min even when a low temperature of 60 °C was used to regenerate the adsorbent.