Can graphene be used as a substrate for Raman enhancement?
By X. Ling, Liming Xie, Yuan Fang, Hua Xu, Haoli Zhang, Jing Kong, Mildred S. Dresselhaus, Jin Zhang, Zhongfan Liu. Nano letters (Print), 2010
981 citations recorded by the source corpus.
Graphene is a monolayer of carbon atoms packed into a two-dimensional (2D) honeycomb crystal structure, which is a special material with many excellent properties. In the present study, we will discuss the possibility that graphene can be used as a substrate for enhancing Raman signals of adsorbed molecules. Here, phthalocyanine (Pc), rhodamine 6G (R6G), protoporphyin IX (PPP), and crystal violet (CV), which are popular molecules widely used as a Raman probe, are deposited equally on graphene and a SiO(2)/Si substrate using vacuum evaporation or solution soaking. By comparing the Raman signals of molecules on monolayer graphene and on a SiO(2)/Si substrate, we observed that the intensities of the Raman signals on monolayer graphene are much stronger than on a SiO(2)/Si substrate, indicating a clear Raman enhancement effect on the surface of monolayer graphene. For solution soaking, the Raman signals of the molecules are visible even though the concentration is low to 10(-8) mol/L or less. What's more interesting, the enhanced efficiencies are quite different on monolayer, few-layer, multilayer graphene, graphite, and highly ordered pyrolytic graphite (HOPG). The Raman signals of molecules on multilayer graphene are even weaker than on a SiO(2)/Si substrate, and the signals are even invisible on graphite and HOPG. Taking the Raman signals on the SiO(2)/Si substrate as a reference, Raman enhancement factors on the surface of monolayer graphene can be obtained using Raman intensity ratios. The Raman enhancement factors are quite different for different peaks, changing from 2 to 17. Furthermore, we found that the Raman enhancement factors can be distinguished through three classes that correspond to the symmetry of vibrations of the molecule. We attribute this enhancement to the charge transfer between graphene and the molecules, which result in a chemical enhancement. This is a new phenomenon for graphene that will expand the application of graphene to microanalysis and is good for studying the basic properties of both graphene and SERS.
Subfields: Electronic, Optical and Magnetic Materials, Materials Chemistry
View Paper: https://www.semanticscholar.org/paper/537432e9914856d7a90b65000a76e0b088202790
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Electronic, Optical and Magnetic Materials
In Materials Chemistry
Citations in the corpus
- UV light exposure of aqueous graphene oxide suspensions to promote their direct reduction, formation of graphene–metal nanoparticle hybrids and dye degradation (2012, background): “[55] Ling X, Xie L, Fang Y, Xu H, Zhang H, Kong J, et al.”
- Graphene: A Rising Star on the Horizon of Materials Science (2012, background): “They found that graphene has the potential as a substrate for Raman enhancement [72].”