Raman spectroscopy of active-carbon electrodes when Au colloids are placed at the electrolyte/electrode interface

TL;DR

This study employs surface-enhanced Raman spectroscopy to investigate how gold nanoparticle interfaces influence the electrochemical properties of active-carbon super-capacitors, revealing resonance effects and capacitance enhancements.

Contribution

It demonstrates the use of SERS to analyze Au nanoparticle effects at the electrolyte/electrode interface in super-capacitors, a novel application in this context.

Findings

Resonance-like enhancement in the G-line of A-C electrodes

Capacitance increases with AuNPs concentration

Formation of a quasi-2D AuNP array at the interface

Abstract

We use surface enhanced Raman spectroscopy (SERS) in studying functionalized Au nanoparticles (AuNPs) when incorporated in active-carbon (A-C) based super-capacitor cells. We observe a resonance-like enhancement in the graphitic line (G-line) vs the D-line (defect line) of the A-C electrode. We also observed an enhancement in the specific capacitance of super-capacitor cell as a function of AuNPs concentration. All of these may be explained by the formation of a quasi-2D array of AuNPs at the interface between electrolyte and the electrode.