A DRIFTS study of moisture adsorption on hexagonal mesoporous (HMS) silica supported composites

摘要

Hexagonal Mesoporous Silica (HMS) materials supported composite materials were synthesized to remove trace moisture in the gas insulated switchgear (GIS) in this work. And an infrared study has been performed on the adsorption-desorption process of water vapor on these composites before and after polyethyleneimine (PEI) loading. It was found that the amino groups of PEI at high loading amounts functioned as the main active sites for H2O capture. These adsorbed water clusters tended to associate with composite materials through weak hydrogen-bonding interactions and could be easily regenerated under nitrogen flow. The three-dimensionally interconnected pores of HMS and the maintained alkylamine surfactants facilitated the dispersion of loaded PEI, improving the diffusion and adsorption properties of moisture. The results herein implied that PEI/HMS composites would be a kind of appealing materials for moisture capture in GIS due to its superior moisture adsorption capacity and excellent cyclic performance.