Low-cost and fast synthesis of nanoporous silica cryogels for thermal insulation applications.

Nanoporous silica cryogels with a high specific surface area of 1095 m g were fabricated using tert-butyl alcohol as a reaction solvent, via a cost-effective sol-gel process followed by vacuum freeze drying. The total time of cryogel production was reduced markedly to one day. The molar ratio of solvent/precursor, which was varied from 5 to 13, significantly affected the porous structure and thermal insulating properties of the cryogels.