Influence of the substrate on the self-assemblies of silver sulfide nanocrystals

The influence of the substrate on the morphology of 2D and 3D superlattices made of 5.8 run silver sulfide nanocrystals coated with dodecanethiol is r eported. Two substrates, highly oriented pyrolytic graphite (HOPG) and moly bdenum disulfide (MoS2), are used. Self-assemblies of nanocrystals are char acterized with scanning electron microscopy (SEM), transmission electron mi croscopy (TEM) and atomic force microscopy (AFM) techniques. It is proposed that the different behaviors observed on the two substrates are related to van der Waals interactions between particles and between particle-substrat e as well as to capillary forces. (C) 2000 Elsevier Science B.V. All rights reserved.