Self-assembled thiolate functionalized gold nanoparticles template toward tailoring the morphology of electrochemically deposited silver nanostructure

The evolution of silver particles' morphologies synthesized by electrochemical deposition on highly oriented pyrolytic graphite (HOPG) substrate modified by self-assembled gold nanoparticle (Au NP) was studied. It was found that for a convenient potential, controlling only the temperature causes a change in the deposited silver morphology from dendrite to plate. Interestingly, different average sizes of plate were obtained by varying the deposition time. X-ray diffraction (XRD) measurements show that plates grow preferentially along the (1 1 1) direction. The surface mobility of thiolate covered Au NP surfaces was believed to be the cause of the temperature-induced morphology evolution of deposited silver. Scanning electrochemical microscopy (SECM) was used to probe charge transfer between ferricyanide electroactive ionic species and electrodeposited silver particles modified by self-assembled monolayer (SAM) of dodecanethiol. The observed phenomena indicate that the electron transfer (ET) process is affected by the properties of the dodecanethiol SAM on deposited silver particles. (C) 2012 Elsevier Ltd. All rights reserved.