| Popis: |
This work demonstrated the synthesis of SiO2-P2O5-SnO2-ZnO quaternary porous aerogel by sol-gel followed supercritical carbon dioxide drying, starting from tetraethoxysilane (TEOS) as precursor for SiO2and triethyl phosphate, tin (iv) chloride pentahydrate and zinc nitrate hexahydrate as precursor for P2O5-SnO2-ZnO. It has been recorded that prepared P2O5-SnO2-ZnO sol was added to silica sol, then formed the quaternary aerogel by base catalyst. The microstructure, morphology and properties of the quaternary aerogel were studied by TG/DTA, FTIR, solid-state29Si NMR, BET, scanning electron microscopy (SEM) measurement and BJH nitrogen gas adsorption. The silica aerogels tetrahedral subunit structure and the influence of the loaded oxide have been observed. The results indicated that the quaternary aerogel exhibited average pore diameter of 14.15 nm, cumulative pore volume of 2.31 ml/g, the specific surface area as high as 796.29 m2/g and bulk density of 0.275g/cm3. There were four types of Si (O1/2)4tetrahedral unit structure in the quaternary aerogel. From this study, different chemical bond of P2O5-SnO2-ZnO penetrated into the silica network structure. |
