Functionalization of glassy carbon with diazonium salts in ionic liquids.
The paper reports on the chemical functionalization of glassy carbon electrodes with 4-bromobenzene (4-BBDT) and 4-(4'-nitrophenylazo)benzene diazonium tetrafluoroborate (4-NAB) salts in ionic liquids. The reaction was carried out at room temperature in air without any external electrical bias in either hydrophobic (1-butyl-3-methylimidazolium hexafluorophosphate) or hydrophilic (1-butyl-3-methylimidazolium methyl sulfate) ionic liquids. The resulting surfaces were characterized using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and electrochemical measurements. Electrochemical reduction of the terminal nitro groups allowed the determination of surface coverage and formation of an amine-terminated carbon surfaces. The results were compared to glassy carbon chemically modified in an aqueous solution in the presence of 1% sodium dodecyl sulfate (SDS) with the same diazonium salt. Furthermore, Raman spectroscopy coupled with electrochemical measurements allowed to distinguish between the reduction of -NO2 to -NH2 group and the -N=N- to -NH-NH- bond.
Actis
Paolo
P
Laboratoire d'Electrochimie et de Physicochimie des Matériaux et des Interfaces, CNRS-INPG-UJF, 1130 Rue de la Piscine, BP 75, 38402 St. Martin d'Hères Cedex, France.
Caulliez
Guilain
G
Shul
Galyna
G
Opallo
Marcin
M
Mermoux
Michel
M
Marcus
Bernadette
B
Boukherroub
Rabah
R
Szunerits
Sabine
S