Effect of Self-Assembled Monolayers on the Locally Electrodeposited Silver Thin Layers.


Fedorov RG, Mandler D. Effect of Self-Assembled Monolayers on the Locally Electrodeposited Silver Thin Layers. J. Phys. Chem. CJournal of Physical Chemistry C. 2016;120 (29) :15608 - 15617.

Date Published:



The localized electrodeposition of Ag on Au coated with self-assembled monolayers (SAMs) by scanning electrochem. microscopy (SECM) is reported. The SAMs were ω-functionalized alkanethiols X-(CH2)2SH, X = OH, NH2, CO2H, SO3H, as well as 4-mercaptobenzoic acid. The SAMs were characterized by XPS and cycling voltammetry (CV). The anodic dissoln. of a Ag microelectrode, which was held within a few microns from the Au surface, formed a well-controlled flux of Ag+. Deposition of Ag nanostructures was driven by the electrochem. redn. of the Ag+ on the Au surface. The effect of the functional group on the Ag local deposition was studied and compared with bulk deposition on the same SAMs. For bulk deposition, the interaction between Ag+ ions and the functional group of the alkanethiols slowed the kinetics of Ag deposition, shifting the deposition to potential that is more neg. and caused the formation of large, well-faceted Ag crystals. A clear correlation between the potential shift value and the morphol. of deposited Ag was obsd. The local deposition of Ag showed distinct difference compared to bulk deposition. A continuous and homogeneous Ag film was formed locally below the Ag microelectrode in the presence of a 3-mercaptopropionic acid monolayer. This was obsd. when a 120 s delay between the electrogeneration of the Ag ions and the application of a neg. potential to the Au surface was applied. Also, the potential applied to the Au surface also affected deposition. The deposited Ag was recollected by the Ag microelectrode by stripping the Ag from the Au surface while holding the microelectrode in the same position. This enabled calcg. the thickness of the Ag film deposited on the Au coated with 3-mercaptopropionic acid. Addnl. expts. clearly indicated that the mechanism of deposition involved complexation of Ag ions by the SAM and their local redn., which commenced prior to applying a neg. potential to the Au surface. [on SciFinder(R)]


CAPLUS AN 2016:39246(Journal; Online Computer File)