Titanium dioxide nanostructures chemical sensor
Authors: Bertuna A., Comini E., Poli N., Zappa D., Sberveglieri G.
Autors Affiliation: Univ Brescia, SENSOR Lab, Via D Valotti 9, I-25133 Brescia, Italy; CNR INO, Via D Valotti 9, I-25133 Brescia, Italy
Abstract: Titanium dioxide (TiO2) nanostructures were grown directly on the sensitive area of the transducer. A titanium thin film was deposited on 2 . 2 mm(2) alumina substrates by RF magnetron sputtering and hydrothermal method was used to achieve TiO2. This method is characterized by the use of different solutions (KOH, NaOH), a not stirred pressure reactor and a heating system. As-prepared samples require an acid treatment followed by a calcination step to obtain pure TiO2 nanostructures. The nanostructured morphology was confirmed by a scanning electron microscope (SEM) and their structural properties were investigated by RAMAN spectroscopy. Obtained samples were used as gas sensors, and their behaviour towards several gaseous species was analysed in a wide range of working temperatures. Measurements were carried out in a test chamber, investigating the change in the electrical conductance due to the surrounding atmosphere.
KeyWords: Titanium dioxide; nanostructures; hydrothermal treatment; chemical sensor; Raman spectroscopy