Surface enhanced Raman spectroscopy of polycyclic aromatic hydrocarbons and molecular asphaltenes

• Published in: Chemical physics letters 2015-01, Vol.620, p.139-143
• Main Authors: Andrews, A. Ballard, Wang, Dongxing, Marzec, Katarzyna M., Mullins, Oliver C., Crozier, Kenneth B.
• Format: Article
• Language: English
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2014.12.014

•SIOM substrates enable rapid acquisition of SERS spectra of complex mixtures.•SERS is critical to obtain Raman spectra from asphaltenes because of fluorescence.•We present the first known SERS spectra of individual asphaltene molecules.•DFT calculations attempt to match spectra with corresponding PAH structures.•The combination of theory and experiment advances asphaltene characterization. We describe, for the first time to the best of our knowledge, the acquisition of surface enhanced Raman spectra (SERS) of asphaltenes. SERS is an especially sensitive probe for aromatic carbon making it ideal to investigate the enigmatic polycyclic aromatic hydrocarbons (PAHs) of asphaltenes, the heaviest, most aromatic components of crude oil. SERS spectra of a known PAH model compound and of asphaltene samples are compared to density functional theory (DFT) calculations of PAH structures. This combination of experimental and theoretical methods represents an advance in the characterization of asphaltenes and other complex mixtures.