Novel single phase vanadium dioxide nanostructured films for methane sensing near room temperature

TL;DR

This study introduces novel vanadium dioxide nanostructured films that demonstrate effective methane sensing capabilities near room temperature, with potential for low-temperature gas detection applications.

Contribution

First report of methane sensing using VO_2 nanostructured films synthesized via pulsed dc-magnetron sputtering and oxidation, highlighting their low-temperature sensing performance.

Findings

Films respond well at 50°C in semiconducting state

Nanostructures exhibit reversible semiconductor-metal transition

Crystalline VO_2 with rod-shaped nano-architectures achieved

Abstract

Methane (CH_4) gas sensing properties of novel vanadium dioxide (VO_2) nanostructured films is reported for the first time. The single phase nanostructures are synthesized by pulsed dc-magnetron sputtering of V target followed by oxidation in O_2 atmosphere at 550 ^oC. The partial pressure of O_2 is controlled to obtain stoichiometric VO_2 with the samples showing rutile monoclinic crystalline symmetry and regions of rod shaped nano-architectures. These nanostructured films exhibit a reversible semiconductor to metal transition in the temperature range of 60-70 ^oC. Gas sensing experiments are carried out in the temperature span from 25 ^oC to 200 ^oC in presence of CH_4. These experiments reveal that the films respond very well at temperatures as low as 50 ^oC, in the semiconducting state.