Characterization of three-dimensional reduced graphene oxide/copper oxide heterostructures for hydrogen sulfide gas sensing application

• Published in: Journal of alloys and compounds Vol. 740; pp. 1024 - 1031
• Main Authors: Mirmotallebi, Mona, Iraji zad, Azam, Hosseini, Zahra Sadat, Jokar, Effat
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 05.04.2018; Elsevier BV
• Subjects: Additives; Adsorption; Chemical synthesis; Copper oxide; Copper oxides; Detection; Gas sensing; Gas sensors; Graphene; Heterostructures; Humidity; Hydrogen sulfide; Relative humidity; Three-dimensional structure; Hydrogen sulfide; Gas sensing; Three-dimensional structure; Copper oxide; Graphene
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2018.01.041

Three-dimensional reduced graphene oxide (3D-rGO) structures decorated with CuO particles (GCu) are synthesized through a simple and scalable method for detection of hydrogen sulfide (H2S) gas. For characterization and investigation of porous structure various techniques were employed. Decorated 3D structures demonstrated higher sensitivity and selectivity in comparison to pure structure. Optimized structure for sensing was obtained through introducing different amounts of CuO. The GCu heterostructures containing 35 μmol of CuO powder demonstrated reproducible response of about 30% to the concentration of 10 ppm at room temperature, while complete recovery was obtained through heating to 150 °C. Sensing behaviour of the samples to H2S gas was investigated at temperatures in the range of 25–150 °C and in different relative humidity levels from 3 to 80%. We discussed the sensing model based on the adsorption of H2S molecules on the additives, and electron injection to the sample, resulting in the electrical resistance enhancement. [Display omitted] •3D porous structures of rGO/CuO were synthesized through a simple chemical method.•Optimized concentration of CuO for gas sensing was found to be 35 μmol, labelled as GCu-3.•The structure is a room temperature, sensitive and selective H2S gas sensor.•Sensing behaviour was attributed to chemical doping of the sensor by H2S adsorption.