Formation of rectifier with gold nanoclusters

TL;DR

This paper demonstrates that gold nanocluster films with controlled asymmetry can function as diodes, with their rectification properties characterized by electrical measurements and surface analysis techniques.

Contribution

It introduces a method to create rectifying nanostructures using gold nanoclusters with engineered spatial asymmetry, advancing molecular electronics.

Findings

Gold nanocluster films exhibit diode-like rectification.

Controlled asymmetry is key to rectification in these nanostructures.

Surface characterization confirms the structural basis for electrical behavior.

Abstract

Gold nanoclusters encapsulated with organic molecules are of great interest for its possible applications in the fields of molecular electronics, catalysis and medical science. Here we demonstrate that monolayer and bilayer films of thiol-capped gold nanoclusters can exhibit diode-like properties provided controlled spatial asymmetry exist between two tunnel junctions used to connect a thiol capped gold nanoclusters. Current-voltage characteristics of this rectifier were obtained from conducting probe atomic force microscopy measurements and also from conventional two probe resistance measurements. Systematic x-ray reflectivity and atomic force microscopy measurements were carried out to characterize the spatial asymmetry introduced by a monolayer of fatty acid salt gadolinium stearate used to deposit thiol-capped gold nanocluster molecules on hydrophilic SiO2-Si(001) substrate by Langmuir Blodgett technique. This information was used to explain prominent rectification observed in these nano-structured films.