Reactions of organic monolayers on carbon surfaces observed with unenhanced Raman spectroscopy

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:466472

Liu, Yi-chun; McCreery, R L ^[1]

---

1. Ohio State Univ., Columbus, OH (United States)

High sensitivity surface Raman spectroscopy was used to study a covalently bonded monolayer film and its reaction products. The surface modification is based on reductive formation of nitrophenyl radical from a diazonium derivative, followed by covalent binding to the carbon surface. If the electrolysis is allowed to continue for a long enough time, the surface will be nearly covered by a closed-packed monolayer of {open_quotes}aryl{close_quotes} groups. The grafting of the nitrophenyl group was investigated on various carbon surfaces including glassy carbon (GC), and highly ordered pyrolytic graphite (HOPG). Raman spectroscopy with a 488nm laser and a CCD spectrograph revealed spectral features characteristic of the nitrophenyl group. Isotherm data confirms the existence of the monolayers and their stability to vigorous sonication. In addition, spectral changes of the Raman bands were observed upon the reduction of the attached nitro group to an amino group. Vibrational assignments of the Raman spectra along with supplementary XPS data confirmed that the nitrobenzene was chemisorbed on the carbon surfaces studied.

• OSTI ID: 466472
• Report Number(s): CONF-951017--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
CARBON
CHEMISORPTION
NITROBENZENE
RAMAN SPECTRA
SURFACE PROPERTIES