Graphene Oxide based Gas Sensor for Triethylamine Detection at Room Temperature

Abstract

We have developed a graphene oxide (GO) based sensor to detect triethylamine at room temperature. GO is synthesized by modified Hummer’s method and spin-coated on fluorine-doped tin oxide (FTO) substrate. Structural and morphological characterizations of GO are done by XRD and FE-SEM. Sheet-like morphology of GO is observed in FESEM images. The existence of defects is confirmed by Raman spectra with a ID/IG ratio ∼ 0.94. Gas adsorption studies are carried out using scanning Kelvin probe system with various volatile organic compounds (VOCs) like ethanol, acetone, n-hexane and triethylamine. Among them, GO shows more contact potential difference (CPD) response towards triethylamine. Then, a gas sensor device is fabricated using GO and its electrical characterization is done by I-V measurements. The device shows ohmic behavior with a resistance of ∼ 50 MΩ. Thereafter, the sensor is exposed to triethylamine from 19 to 151 ppm and the sensitivity is 1.39 x 10−4 ppm−1. Interestingly, a fast response time of 11 sec is achieved at room temperature.