An Easy Way To Prepare Monolithic Inorganic Oxide Aerogels

Inorganic oxide aerogels have unique thermal, optical, electrical, magnetic, and chemical properties, which result in them potentially having a broad range of applications. However, their preparation is commonly based on a supercritical drying method, which greatly limits real applications of aerogels and their commercialization. Here we demonstrate a general method for drying wet gels to form aerogels that is based on the sublimation of organic solvent. The organic solvent must have a low surface tension, undergo sublimation easily, and have a high freezing point to allow the rapid synthesis of monolithic inorganic oxide aerogels under vacuum conditions. This cost-effective process will facilitate application of aerogel materials. This approach may also be used for the preparation of other porous materials, whose theoretical and practical applications should be investigated. Graphical Not cracking up : A drying method based on the sublimation of organic solvent allows the rapid synthesis of the monolithic inorganic oxide aerogels without cracks from wet gels. The method proceeds by endothermic evaporation of organic solvent at the outer surface followed by sublimation of solidified solvent (see picture).