A hydrogen gas sensor using a Pt-sputtered MWCNTs/ZnO nanostructure

In the present work, a hydrogen gas sensor of moderate sensitivity utilizing multiwalled carbon nanotubes partially decorated with zinc oxide nanoparticles (MWCNTs/ZnO) has been fabricated. To further enhance its sensitivity, nanoparticles of platinum (Pt) metal have been deposited via a sputtering technique on the MWCNTs/ZnO layer. The sensing materials were characterized by scanning electron microscopy (SEM), Raman and x-ray diffraction (XRD) spectroscopy. The MWCNTs/ZnO/Pt sensor shows a low recovery time of ~78 s and good repeatability when exposed to a 0.05% concentration of H2 gas at room temperature. Moreover, the sensitivity achieved for the MWCNTs/ZnO/Pt sensor is 4.2% as compared to 1.6% for MWCNTs/ZnO for 1% concentration of H2 gas. To the best of our knowledge, such a low concentration of H2 gas detection is reported for the first time using a MWCNTs/ZnO/Pt hybrid nanostructure at room temperature.