title: Improved Selectivity and Sensitivity of Gas Sensing Using a 3D Reduced Graphene Oxide Hydrogel with an Integrated Microheater.
abstract: Low-cost, one-step, and hydrothermal synthesized 3D reduced graphene oxide hydrogel (RGOH) is exploited to fabricate a high performance NO2 and NH3 sensor with an integrated microheater. The sensor can experimentally detect NO2 and NH3 at low concentrations of 200 ppb and 20 ppm, respectively, at room temperature. In addition to accelerating the signal recovery rate by elevating the local silicon substrate temperature, the microheater is exploited for the first time to improve the selectivity of NO2 sensing. Specifically, the sensor response from NH3 can be effectively suppressed by a locally increased temperature, while the sensitivity of detecting NO2 is not significantly affected. This leads to good discrimination between NO2 and NH3. This strategy paves a new avenue to improve the selectivity of gas sensing by using the microheater to raise substrate temperature.
authors.affiliation: School of Mechanical and Aerospace Engineering, Nanyang Technological University , Singapore 639798, Singapore.
authors.forename: Jin
authors.initials: J
authors.lastname: Wu
authors.affiliation: School of Mechanical and Aerospace Engineering, Nanyang Technological University , Singapore 639798, Singapore.
authors.forename: Kai
authors.initials: K
authors.lastname: Tao
authors.affiliation: School of Mechanical and Aerospace Engineering, Nanyang Technological University , Singapore 639798, Singapore.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Miao
authors.affiliation: Center for Environmental Sensing and Modeling (CENSAM), Singapore-MIT Alliance for Research and Technology (SMART) Centre, Singapore 117543, Singapore.|Department of Architecture, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors.forename: Leslie K
authors.initials: LK
authors.lastname: Norford
keywords: NO2; gas sensor; microheater; reduced graphene oxide hydrogel; selectivity; three-dimensional structures