Electrochemical and quartz crystal microbalance (EQCM) methods are used to probe the redox behavior of self-assembled monolayers of viologen derivatives with long alkyl chains and disulfide or thiol groups that provide for attachment to gold electrodes. The EQCM measurements revealed that cations exit and enter the viologen monolayer during reduction and oxidation, respectively. In this study, the self-assembly process of viologen was monitored using resonant frequency (ΔF) and resonant resistance (ΔR). The QCM measurements indicated a mass adsorption for viologen assembling on the gold surface with a frequency change of approximately 135 Hz and calculated its surface coverage (Γ) to be 3.5273×10-9 mol/cm2. Also, a reversible redox process was observed and analyzed with an ionic interaction at the viologen/solution interface using ΔF.

No abstract

No abstract