Rapid synthesis of dual-mesoporous silica aerogel with excellent adsorption capacity and ultra-low thermal conductivity

Abstract In this paper, using methyltriethoxysilane (MTES) and tetraethoxysilane (TEOS) as co-precursor, dual-mesoporous silica aerogel was rapidly prepared within 20 h by ambient pressure drying. The dual-mesoporous structure can be obtained just by control the amount of TEOS. The skeleton structure of the dual-mesoporous aerogel is composed of small mesopores (3-6 nm) and large mesopores (17-30 nm). Moreover, the thermal conductivity (as low as 0.0223 W/(mK)) of the dual-mesoporous aerogel is much lower than most of MTES-based aerogels. More importantly, the obtained dual-mesoporous aerogel can separate oil from surfactant-stabilized oil-in-water emulsion, the separation efficiency as high as 97.6%. In addition, the aerogel exhibits superhydrophobic with a contact angle of 157.4°, thermally stable reaching up to 489.5°C and outstanding sorption capacity reaching up to 8.4-17.1 g/g. The dual-mesoporous silica aerogel have potential application in thermal insulating and organic pollutants sorption.