DC Magnetron sputtered V2O5 thin films for sensitive detection of hydrogen gas at room temperature

Abstract

Abstract Hydrogen (H2) gas sensing studies of direct current magnetron sputtered vanadium oxide (V2O5) thin films were sputtered at different partial pressures of oxygen to modify their stoichiometry, morphology, and grain size for efficient H2 detection at room temperature. This drastically enhanced the H2 adsorption sites of improved responsivity. The sample also showed good selectivity to H2 and ammonia, acetone, ethanol, and toluene. The microstructure and morphology studies of materials were analyzed by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and Raman analysis. Structural study of pure V2O5 thin films showed amorphous nature with the (100) direction orientation. SEM image surface morphology explored the small flower-like morphology. From the optical study, the transmittance and band gap has decreased due to increasing substrate temperature. Specifically, H2 was measurable with concentrations ranging from 50–500 sccm (standard cubic centimeter) at room temperature in 1000 sccm dry N2. The results showed that a good sensitivity towards H2 was obtained with a thin film sensor at the optimal operating temperature of room temperature (27°C) and also showed good selectivity. The gas response, response time, and recovery time were measured.