Long range self-organisations of small metallic nanocrystals for SERS detection of electrochemical reactions - Archive ouverte HAL Access content directly
Journal Articles Journal of Electroanalytical Chemistry Year : 2020

Long range self-organisations of small metallic nanocrystals for SERS detection of electrochemical reactions

(1) , (1) , (1) , (2, 3) , (2, 3) , (3) , (3) , (3) , (2) , (3)
1
2
3

Abstract

Gold electrodes were modified by silver and gold nanocrystals (NCs) that self-organize onto the surface. Their optical properties were explored by measuring electroreflectance spectra as a function of electrode potential. Below their oxidation potential, no shift of the reflectance maximum was observed for Ag NCs. This can be explained by a low inter-facial capacitance resulting from the impossibility for the electrolyte to penetrate into the hydrophobic layer created by the NCs dodecanethiol ligands. Conversely, a non-monotonous evolution was observed with the electrode potential for oleylamine capped Au NCs. This behavior is suggesting a less dense hydrophobic layer, allowing significant electrolyte penetration. Next, electroactive compounds were adsorbed on the the Au NCs assemblies and characterized by Raman spectroelectrochemistry. In the first system displaying a single electron transfer with no coupled chemical reaction, only the spectrum intensity changed, because oxidation generated a Raman resonant radical cation. The second study considered 4-nitrothiophenol, for which up to 6 electrons and 6 protons may be transferred. In this case, the nitro band disappeared upon reduction, and the spectrum displayed typical features of the formed 4-aminothiophenol.
Fichier principal
Vignette du fichier
SERS_NPs_2020_HAL.pdf (429.26 Ko) Télécharger le fichier
Origin : Files produced by the author(s)
Loading...

Dates and versions

hal-02954128 , version 1 (30-09-2020)

Identifiers

Cite

Sihem Groni, Claire Fave, Bernd Schöllhorn, Lionel Chapus, Pierre Aubertin, et al.. Long range self-organisations of small metallic nanocrystals for SERS detection of electrochemical reactions. Journal of Electroanalytical Chemistry, 2020, 872, pp., 114322. ⟨10.1016/j.jelechem.2020.114322⟩. ⟨hal-02954128⟩
229 View
115 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More