Synthesis of One Atom Thin, Two-Dimensional Gold Films and Their Novel Properties

TL;DR

This paper reports the first synthesis of one atom thick 2D gold films with novel semiconducting properties, nanoring formations, and a reproducible mirror structure creation process on silicon and sapphire substrates.

Contribution

It introduces a new technique for synthesizing atomically thin gold films and explores their unique electrical and structural properties, including self-assembly and mirror structure formation.

Findings

Gold films are semi-conducting with high turn-on voltage.

Self-assembled nanorings of 2D gold structures were observed.

Mirror structures can be reproducibly created with a finite lifetime.

Abstract

Though significant advances have been made in the field of metal nanostructures, researchers are yet to synthesize one atom thin two-dimensional 2D gold nanostructures. We report, for the first time, a technique to synthesize one atom thin gold films and membrane like porous films on silicon and sapphire. These films were essentially liquid at room temperature. Current-Voltage spectroscopy using atomic force microscopy revealed a typical Schottky behavior with a very high turn on (knee) voltage at 4.15V indicating that these 2D gold structures are semi-conductors. Nanorings comprising self assembled one atom thin gold structures on sapphire were also observed. Subjecting one nanoring in a group of several nanorings to a point force of 2.25 micro newton for 120 seconds resulted in the creation of a mirror structure, accompanied by every nanoring in the group to simultaneously create its individual mirror structures. These mirror structures had an apparent spatial and temporal correlation to each other. They had a finite life time of a few hours and the process was repeatable to a great degree of precision.