A facile method to prepare noble metal nanoparticles modified Self-Assembly (SAM) electrode

Abstract

Noble metal nanoparticles (NPs) modified electrodes have shown promising applications in the areas of catalysis, (electro)chemical analysis and biosensing due to their unique characters. In this paper, we introduced a so-called ligand exchange method to prepare self-assembly (SAM) electrode modified with noble metal nanoparticles. The noble metal nanoparticles protected by weakly adsorbed tetraoctylammonium bromide (TOAB) were synthesized firstly, then self-assembly (SAM) dithiol-modified Au electrode (Au-SH SAM ) was immersed into the solutions containing TOAB-protected nanoparticles. Due to the strong interaction between the dithiol groups on the electrode and noble metal nanoparticles, the weakly adsorbed TOAB on the surface of noble metal NPs were replaced by dithiol groups. As a result, the TOAB protected NPs were anchored on the Au-SH SAM template electrode surface by ligand exchange, obtaining noble metal NPs modified electrode with high quality and stability. By adjusting the soaking time, the coverage of nanoparticles on the Au-SH SAM electrode surface could be controlled. The morphology and distribution of noble metal NPs on Au-SH SAM surface was analysis by scanning tunneling microscope (STM), and their electrochemical property was studied by cyclic voltammetry (CV) in H 2 SO 4 solution. The approach is proved as a universal way to prepare noble metal NPs modified SAM electrode.

Effect of Supporting Background Electrolytes on the Nanostructure Morphologies and Electrochemical Behaviors of Electrodeposited Gold Nanoparticles on Glassy Carbon Electrode Surfaces

“…11 In the case of the electrodeposition of metal nanomaterials onto the electrode surfaces, the reduction peak is an indicator of the electrodeposition process, in which metal ions in the electrolyte solution are reduced to metal nanoparticles under the potential cycles by accepting the electron(s), thus producing electrodeposited metal nanoparticle films on the electrode surface. 12 Among the metal nanoparticles [such as platinum (Pt), gold (Au), silver (Ag), and palladium (Pd)], Au nanoparticles are the most commonly used metal nanomaterials in electroanalysis (electrochemical sensors and biosensors) and electro-catalysis due to their unique characteristics, such as high biocompatibility for the immobilization of biomolecules, in particular, via a self-assembly monolayer technique, 6,13 electrocatalytic properties, high electroactive surface areas (ECSAs), and mass transport enhancement. 2,10,14 Thus, gold-nanostructured forms offer enhanced electrochemical responses compared to the bulk Au electrodes as each Au nanoparticle electrodeposited at the modified electrode can perform as a tiny electrode, improving the electrical conductivity of the electrode surface.…”

“…The CV technique can also provide us with a cyclic voltammogram for the electrodeposition of metals onto the electrode surface, which allows us to monitor both the oxidation and reduction peaks for dissolution and electrodeposition processes of metals and metal ions from the electrode surface . In the case of the electrodeposition of metal nanomaterials onto the electrode surfaces, the reduction peak is an indicator of the electrodeposition process, in which metal ions in the electrolyte solution are reduced to metal nanoparticles under the potential cycles by accepting the electron(s), thus producing electrodeposited metal nanoparticle films on the electrode surface …”

Surface Plasmon Resonance-Based Immunosensor for Igm Detection with Gold Nanoparticles

“…In the first step, the gold surface of the SPR chip was washed with acidic piranha solution [sulfuric acid/hydrogen peroxide (3:1 v/v )] for nearly 3 min, then was rinsed with DW, and dried in a vacuum oven (200 mmHg, 40 °C). After that, the gold sensing surface was modified according to a previous study [ 26 ] by using an ethanol solution containing 1,8-octanedithiol (4.3 mM) for 12 h, and the excess of 1,8-octanedithiol on the sensing surface was removed with an ethanol solution and rinsed with DW.…”

Stimuli‐triggered Self‐Assembly of Gold Nanoparticles: Recent Advances in Fabrication and Biomedical Applications

“…Moreover, the 3D structure of AuNPs superlattices was determined by small-angle X-ray scattering. Liu et al [44] introduced a ligand exchange method to prepare self-assembly electrode-modified gold nanoparticles that exhibit great quality and stability. This prepared AuNPs with the modification of SAM electrode showed great potential in biosensing application.…”