Sensoristic applications of self-assembled mesostructured silica films

Electrochemical sensors developed from mesostructured silica film have been fabricated through evaporation-induced self-assembly via dip-coating on various substrates with interdigitated electrodes. The silica films exhibited ordered mesoporous phases that were maintained after the copolymer removal. A large current variation (up to four orders of magnitude) has been observed during relative humidity changes in the testing chamber. The performance of the sensors has been found to be dependent on the film preparation method, especially on the calcination temperature and the length of time it is maintained. A different response as a function of the surfactant used as templating agent has been obtained. The electrical response of the devices was studied at various concentrations of alcohol vapor (methanol, ethanol, isopropanol, and n-butanol).