Preparation of sol-gel derived SiO2 and Al2O3 layers with designed nanoporosity

The sol-gel process was used to prepare nanoporous (typically micro and mes oporous) supported layers from silica and alumina sols. The control of agin g time for silica gel layers, the investigations of new alumina hydrosols a nd the general use of removable templating mesophases are crucial parameter s to produce layers exhibiting unconventional porosity. Quasidense micropor ous layers as well as silica layers with a mesoporosity up to 74% were obta ined, All these described methods allow the easy preparation of supported c rack-free layers with several potential applications.