Transistor behavior via Au clusters etched from electrodes in an acidic gating solution: metal nanoparticles mimicking conducting polymers

TL;DR

This study demonstrates a reversible transistor-like switching behavior in gold electrode systems caused by electrochemical etching of Au nanoparticles, which mimics conducting polymer transistors and could affect molecular-electronics interpretations.

Contribution

It reveals that Au nanoparticle etching induces transistor-like conductance switching, highlighting a potential confounding factor in nanoscale electrochemical experiments.

Findings

Conductance switches from off to on to off with gate voltage.

Etched Au nanoparticles cause electrochemical ICI transistor behavior.

Mimics characteristics of acid-gated conducting polymer transistors.

Abstract

We report that the electrical conductance between closely-spaced gold electrodes in acid solution can be turned from off [insulating; I] to on [conducting; C] to off again by monotonically sweeping a gate voltage applied to the solution. We propose that this ICI transistor action is due to an electrochemical process dependent on nanoparticles etched from the surface of the gold electrodes. These measurements mimic closely the characteristics of nanoscale acid-gated polyaniline transistors, so that researchers should guard against misinterpreting this effect in future molecular-electronics experiments.