Abstract
Oxygen plasma treatment has been reported as an effective way of improving the response of graphene gas sensors. In this work, a gas sensor based on a composite graphene channel with a layer of pristine graphene (G) at the bottom and an oxygen plasma-treated graphene (OP-G) as a covering layer was reported. The OP-G on top provided oxygen functional groups and serves as the gas molecule grippers, while the as-grown graphene beneath serves as a fast carrier transport path. Thus, the composite channel (OP-G/G) demonstrated significantly improved response in NH3 gas sensing tests compared with the pristine G channel. Moreover, the OP-G/G channel showed faster response and recovering process than the OP-G channel. Since this kind of composite channel is fabricated from chemical vapor deposited graphene and patterned with standard photolithography, the device dimension was much smaller than a gas sensor fabricated from reduced graphene oxide and it is favorable for the integration of a large number of sensing units.
Highlights
Gas detection and recognition is very important in both industry and daily life applications.Especially with the development of the Internet of things (IoT), the demand for miniaturized gas sensors with low power consumption will increase dramatically
The results of our work show the oxygen plasma-treated graphene (OP-G)/G composite channel has significantly improved sensitivity compared with pristine G and much faster response and recovering process compared with a mono layer OP-G channel
Both as-grown oxygen plasma-treated graphene were transferred with Polymethyl Methacrylate (PMMA) as transfer and oxygen plasma-treated graphene were transferred with Polymethyl Methacrylate (PMMA) as vehicle and a (NH4 )2 S2 O8 solution as copper foil etching agent
Summary
Gas detection and recognition is very important in both industry and daily life applications. Nanoparticle decoration and chemical treatment are widely explored to enhance both the sensitivity and specificity in gas sensing [10,11,18,19,20,21] Those procedures introduce functional groups or defects on the graphene surface and provide effective molecule adsorption sites. Increasing the effective adsorption sites while maintaining high carrier mobility is one of the major challenges, we are facing in the development of a graphene gas sensor To address this challenge, here we propose a gas sensing channel with composite double layer graphene: a layer of pristine graphene at the bottom and a layer of functionalized graphene on the top. The results of our work show the OP-G/G composite channel has significantly improved sensitivity compared with pristine G and much faster response and recovering process compared with a mono layer OP-G channel
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
