Mesoporous thin films as versatile sensitive matrices on Love wave sensors for fast sub-ppm vapor detection

Love wave gas sensors with mesoporous thin film as sensitive layers are presented. They are dedicated to volatile organic compound vapor detection. Mesoporous films of SiO
₂
were prepared using the sol-gel process and deposited on the devices acoustic path. The obtained films have been characterized by ellipsometry resulting in the determination of porosity and pore size distribution in the film and of water adsorption isotherms. Ethanol (130-2000 ppm) and toluene (70-1000 ppm) exposures resulted in frequency shifts up to 20 kHz, showing the high sensitivity of the mesoporous-based Love wave devices.