The gas sensor based on carbon nanotubes are presently receiving considerable attention because of the outstanding
properties, such as faster response, higher sensitivity, lower operating temperature and robustness of the nanotubes in
comparison with the other types of sensing materials.
In the present research, we demonstrate detection of hydrogen at room temperature using a Quartz Crystal Nano-balance
(QCN) and as sensing material, Single-Walled Carbon Nanotubes (SWCNTs) dispersed in a polythiophene matrix. The
experimental determination of H2 in H2/N2 mixtures has been performed by using a counter frequency and observing the
frequency shifts induced in a quartz crystal resonator by H2 adsorption and consequent mass variation of the active layer
deposited on the quartz.
The high sensitivity of the realized nano-balance allows us to observe mass variations up to few nanograms /Hertz and to
detect up to 1% of H2. The good sensing performances of the nanotube-based material make unnecessary the use of any
catalyst species for H2 detection. Moreover this QCN device is able to work with good efficiency at 23 °C and 1 Atm.
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