Thin films of thiol-derivatized gold nanocrystals

Thin films of thiol-derivatized gold nanocrystals have been formed on amorphous carbon substrates by air drying toluene solutions of these nanocrystals and studied using transmission electron microscopy (TEM). These nanocrystals form both monolayer and bilayer films. Close-packed regions can be identified in monolayer films while the nanocrystals appear to form network-like structures in bilayer films. Toluene solutions containing bimodal distributions of nanocrystals form, upon drying, films in which the nanocrystals appear to occupy distinct regions of the film on the basis of their size. Electron diffraction of these films in conjunction with particle size measurements from TEM images is used to provide support for the possible interpenetration of the monolayers formed by dodecanethiol on adjacent nanocrystal surfaces in close-packed regions.