Nanofabrication and Electrochemical Characterization of Self-Assembled Monolayers Sandwiched between Metal Nanoparticles and Electrode Surfaces

Abstract

Nanoscience and nanotechnology have reached the syllabi of many upper-division undergraduate and master-level courses all over the world. There is therefore a growing need for practical exercises that illustrate the fabrication, characterization, properties and applications of nanomaterials. Here we describe an advanced-level laboratory experiment in which students had the opportunity to fabricate surfaces modified by ordered monolayers and nanostructured materials. The surface modification was quantified by means of a quartz crystal microbalance, whilst the electrochemical properties of the nanoarchitectures were assessed using cyclic voltammetry experiments. Electron transfer across self-assembled monolayers mediated by gold nanoparticles was presented as a topic for discussion, and consideration of potential practical applications of the observed phenomena (catalytic and electrocatalytic processes as well as development of optical, (opto)electronic and photovoltaic devices with enhanced properties) was proposed as a further reading exercise.

Electrically transmissive alkyne-anchored monolayers on gold

“…Such behavior has been reported for gold electrodes modified by aryl-monolayer 74,75 or by oligo(phenylene ethynylene) derivatives anchored through various groups including thiols, amines and carboxylic acids. 12,14,31,60,61,76,77 The reversible two-peaked diffusion-controlled electrochemical response of the 2b). Therefore on the timescale of these voltammetric determinations the monolayer of 1 is nearly transparent to the electron transfer process, which is in stark contrast with other monolayers of other OPE compounds that significantly or completely block the electrode.…”

“…The working electrode was a gold substrate from Arrandee™ (either the bare gold electrode or the gold electrode covered by a SAM of 1) connected to the potentiostat by means of a cable terminated in a metallic crocodile clip that held the electrode. 60 The reference electrode was Ag/AgCl, KCl (3M), and the counter electrode was a Pt sheet.…”

Hydrogen Peroxide Oxidation Reaction on a 4-Mercaptopyridine Self-Assembled Monolayer on Au(111) Metallized by Platinum Nanoislands

“…Besides the reactivation of the Au substrate for HPOR, the Pt islands seem also to contribute to the overall electrocatalytic activity. It is known that metal nanoparticles on top of an SAM can restore the electron transfer through the adsorbed molecules to the underlying electrode [37,38]. In the presence of metal nanoparticles, electrons can hop to the Au(111) surface and vice versa.…”

Remediating Polluted Soils Using Nanotechnologies: Environmental Benefits and Risks

“…This technology has been reported to be beneficial in medicine [136][137][138][139][140], physics [136,141], genetics [142][143][144], and, most recently, in environmental sciences, among many other areas [123,[145][146][147]. We must highlight the fact that nanotechnologies have been reported as reliable [148], feasible [140], promising [149], practical [150], precise [151], cheap and effective [152], emerging [153], powerful [154], and economically feasible [155].…”