A High-Sensitivity Hydrogen Gas Sensor Based on Carbon Nanotubes Fabricated on Glass Substrate

Abstract

A hydrogen (H2) gas sensor had been fabricated using a carbon nanotube (CNT) which was produced via a conventional microwave oven. It was deposited onto a glass substrate between two Palladium (Pd) electrodes using the dielectrophoretic deposition method. The hydrogen sensing capability of the multiwall carbon nanotube (MWCNT) gas sensor was determined at different operating temperatures and gas concentrations, ranging from 20 ppm to 1000 ppm. The results indicate that the gas sensor exhibits high sensitivity, up to 240% upon exposure to 1000 ppm of H2 at room temperature (RT). Additionally, at room temperature, the sensor shows an excellent sensitivity of 31% when exposed to a very low H2 gas concentration of 20 ppm. The fabricated MWCNT sensors displayed excellent reproducible and reversible responses towards hydrogen at room temperature. Furthermore, MWCNTs were fabricated onto a glass substrate for the detection of H2 gas without the supplementary assistance of metal decoration, vacuum system, or additional film coatings. The high response, low cost, fast recovery, and low power consumption of the fabricated MWCNTs gas sensor validates its superior potential for H2 gas sensing ability at low temperatures.