120th General Meeting of the KCS

Type Poster Presentation
Area Electrochemistry
Room No. Exhibition Hall 2+3
Time 10월 20일 (금요일) 13:00~14:30
Code ELEC.P-486
Subject Sensitive chemiresistive H2O2 gas detection on the ppb level based on graphene decorated with Ag nanowires
Authors Oleksandr Tsymbalenko, Yun Sik Nam1, Kang-Bong Lee2,*
Korea Institute of Science and Technology, Korea
1Advanced Analysis Center, Korea Institute of Science and Technology, Korea
2Green City Technology Institute, Korea Institute of Science and Technology, Korea
Abstract In this study, we demonstrate single-layer graphene decorated with Ag nanowires (AgNWs) for sensitive and selective H2O2 gas sensing. The AgNWs were synthesized by typical polyol method. Single-layered graphene was grown using chemical vapor deposition (CVD) technique and doping with AgNWs was achieved using simple spin-coating pathway. The developed composite have been intensively studied using various characterization methods (SEM, EDS, XPS, and XRD). Our study revealed uniform distribution of AgNWs throughout the graphene substrate. The average diameter of AgNWs is 45 nanometers, with (111), (200) and (220) crystallographic planes. The doping changed the electronic properties of graphene, achieving a drastic resistivity change in the presence of H2O2 gas by converting metallic silver (Ag) to silver oxide (Ag2O), which is a p-type semiconductor. This conversion changes the concentration of charge carriers in the conduction channel of graphene and thus allows to provide real-time H2O2 level monitoring at ambient temperature with a fast response and recovery under UV radiation. Doped graphene has demonstrated the ability to simultaneously, selectively and repeatedly sense H2O2 gas with the saturation time of around 4 min, and with the limit of detection being below 500 ppb.
E-mail t17619@kist.re.kr