Abstract
The chemical vapour sensing behaviour of pristine gallium nitride (GaN) and variously carbon coated GaN (C-GaN) nanostructures towards polar protic (methanol, lactic acid, ammonia, water), polar aprotic (acetone) and apolar (toluene) analytes is investigated. The thickness of the carbon layer on GaN was controlled by using argon or nitrogen as carrier gases for toluene. TEM micrographs revealed dependence of the carbon layer on the carrier gas; with nitrogen (~2.6 ± 0.6 nm) leading to a thinner layer than argon (~3.4 ± 0.7 nm). Interestingly, chemical sensing performance studies showed that the carbon coating improved the sensitivity of GaN to polar protic analytes, especially to the toxic ammonia. Most importantly, enhanced sensitivity was observed for water molecules on the C-GaN based devices in comparison to water sensitivity on bare GaN devices. In contrast, the carbon coating was observed to have little or no influence on the sensitivity towards polar aprotic and apolar analytes. In summary, the study demonstrates the importance of coating GaN nanoparticles with a thin carbonaceous layer for enhanced room temperature sensitive and selective detection of chemical vapour analytes. • GaN and carbon coated GaN nanostructured resistive sensors were studied • Studied analytes were methanol, lactic acid, ammonia, water, acetone and toluene • Carbon coating improves sensitivity of GaN nanostructures to polar protic analytes • The sensors operate at room temperature
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.