Abstract
We report on the relationship between the degree of reduction of graphene oxide (GO) and its room-temperature methane gas-sensing response by comparing four in situ reducing agents of GO: d-glucose, sodium borohydride, l-ascorbic acid and hydrazine hydrate. We found that gas sensing based on d-glucose and l-ascorbic acid had a higher gas response than that based on sodium borohydride and hydrazine hydrate because the residues contained oxygen functional groups. The poorly conductive GO was successfully reduced in situ by l-ascorbic acid to achieve high electrical conductivity and a high methane gas response. The incorporation of tin dioxide (SnO2) into the reduced GO (RGO) further increased the gas response by the p-n junction effect. The heterostructure of l-ascorbic acid-reduced RGO-SnO2had the highest increase in methane response due to the synergistic effect between dehydroascorbic acid and the SnO2surface. This was inferred from density functional theory calculations with self-consistently determined Hubbard U potentials (DFT+U). Compared with the current room-temperature methane sensing and fabrication technologies, the sensing technology reported here is cheaper to produce and more environmentally friendly while retaining the best sensitivity and wider sensing range.
Original language | English |
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Pages (from-to) | 11131-11142 |
Number of pages | 12 |
Journal | Journal of Materials Chemistry A |
Volume | 5 |
Issue number | 22 |
DOIs | |
Publication status | Published - 1 Jan 2017 |
ASJC Scopus subject areas
- Chemistry(all)
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)