Graphene–silver nanohybrids for ultrasensitive surface enhanced Raman spectroscopy: size dependence of silver nanoparticles

摘要: The surface-enhanced Raman scattering (SERS) mechanism of graphene–silver (GE–Ag) nanohybrids was investigated by studying the signals rhodamine 6G (R6G) adsorbed onto with different sizes Ag nanoparticles (NPs). results showed that SERS intensity ratios between GE–Ag NPs 9, 25 and 35 nm pure substrate were estimated to be 2.7, 5.0 8.9 respectively. GE sheets did improve activity due their high adsorption ability, strong fluorescence quenching additional chemical enhancement (CM)-based effect. However, relatively larger size (∼nm) play a major role in molecules on nanohybrids. Furthermore, free-standing NP nanohybrid film fabricated through vacuum filtration optimized composite suspension followed thermal annealing. as-prepared has narrower interparticle distance, which provides more “hot spots” for sensitive detection R6G molecules, limit at 1 × 10−12 M. Additionally, relative standard deviation (RSD) values are measured below 0.13, revealing good consistency reproducibility across entire area film, suggesting this holds promise routine detection.