Plasmon-exciton coupling by hybrids between graphene and gold nanorods vertical array for sensor

The graphene/gold nanorods vertical array (G/GNRs-VA) hybrid substrate was fabricated by self-assembly and wet-etching method, which demonstrated high performance in surface-enhanced Raman scattering (SERS). By combining the excellent electromagnetic (EM) enhancement of the GNRs-VA and the distinctive physical/chemical properties of graphene, the G/GNRs-VA hybrid substrate has high sensitivity, which can detect Raman signal of Rhodamine 6G (Rh6G) at concentrations as low as 10(-13) M. This phenomenon can be easily reproduced in our experiment. Among these randomly selected points, we calculated the relative standard deviations (RSD) at 1360 cm(-1) and 1650 cm(-1), and got the results as7.2% and 7.3%, respectively. Compared with GNRs-VA, hybrid substrates exhibit stronger Raman signal, which is mainly attributed to chemical enhancement (CM) of graphene. COMSOL software was used to simulate local electromagnetic field of the SERS substrate, which is consistent with experimental result. Moreover, G/GNRs-VA hybrid substrate can simultaneously detect Raman signals of Rh6G and crystal violet (CV) at concentration of 10(-9) M. These indicate that the G/GNRs-VA hybrid substrate could provide reliable support for developing environmental detection and biomedical diagnostics. (C) 2018 Elsevier Ltd. All rights reserved.