Vacca A., Mascia M., Rizzardini S., Palmas S., Lai S., Napoli C., Barbaro M., 2014, Functionalization of Polycrystalline Gold Through the Electroreduction of Aryldiazonium Salts in Ionic Liquids, Chemical Engineering Transactions, 41, 79-84.
In this work the electrochemical functionalization of polycrystalline gold with a nitro-phenyl layer has been studied. The surface modification has been performed by cyclic voltammetries through the electroreduction of 4-nitrobenzenediazonium salt (NBD) using as solvent the ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl) imide ([BMP][TFSA]). The presence of phenyl groups on the electrode surface was studied by cyclic voltammetry and electrochemical impedance spectroscopy (EIS). The barrier propriety of nitro-phenyl modified gold surfaces were characterized by EISusing Fe(CN)63- / Fe(CN)64- as a redox probe. The results indicate that nitro-phenyl groups are present ongold surface. The increase in the scan rate during the reduction of NBD in ionic liquid leads to a less covered surface as indicated by a decrease in the charge transfer resistance for the redox probe. Moreover, using the ionic liquid as solvent, lower amount of the attached molecules and a less dense layer are obtained.
