Observation of Electrochemical Single‐Electron‐Transfer Events of Gold Nanoparticles in Aqueous Solution in the Presence of Both Ammonium and Sulfonate Surface‐Active Agents

The synergistic effect of the two surfactants hexyltrimethylammonium bromide and sodium dodecylbenzenesulfonate allows the redox peaks of Au nanoparticles (AuNPs) to be observed in the differential pulse voltammogram of an AuNP-modified Au electrode in aqueous solution (b), whereas in the presence of Et4NClO4 alone no significant peaks ascribable to AuNP redox processes appear due to the high dielectric constant of water (a).