Green synthesis of thermally stable Ag-rGO-CNT nano composite with high sensing activity

• Published in: Composites. Part B, Engineering Vol. 86; pp. 27 - 35
• Main Authors: Khan, Anish, Khan, Aftab Aslam Parwaz, Asiri, Abdullah M., Abu-Zied, Bahaa M.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2016
• Subjects: A. Carbon fibre; A. Nano-structures; A. Polymer-matrix composites (PMCs); B. Electrical properties; Direct current; Dopamine; Electrical resistivity; Fourier transforms; Graphene; Graphene oxide; Nanostructure; Oxides; Silver; A. Polymer-matrix composites (PMCs); B. Electrical properties; A. Nano-structures; Graphene oxide; A. Carbon fibre
• ISSN: 1359-8368; 1879-1069
• DOI: 10.1016/j.compositesb.2015.09.018

Advanced nano composite, containing Ag, was synthesized by coating on reduced graphene oxide (rGO)-carbon nanotube (CNT). Ag-rGO-CNT nanocomposite obtained by hydrothermal treatment of an aqueous dispersion of graphene oxide (GO) and CNTs. After the rGO-CNT composites have been dipped in silver salt solution, the spontaneous redox reaction between these two leads to the formation of nanohybrid materials consisting of rGO-CNT decorated with Ag NPs. Physicochemical characterization of Ag-rGO-CNT was carried out by scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS), fourier transform infrared spectroscopy (FT-IR) and TGA. Electrical resistivity measurements and thermal effect on resistivity of Ag-rGO-CNT was also studied after acid treatment. The dc conductivity was found within the range of 0.08–0.4 Ω cm for pure composite, measured by 4-in line–probe dc electrical conductivity measuring technique. Thermal conductivity is stable with all temperatures in isothermal studies showing excellent stability of Ag-rGO-CNT material. Graphene is attributed to its unique physical and chemical properties, e.g., subtle electronic characteristics, attractive π–π interaction, and strong adsorptive capability. This is used for in-vitro studies of dopamine on carbon fibre microelectrode that shows an excellent performance for dopamine with a detection limit of 0.033 μM and response time of 12s.