title: Dipolar structures in colloidal dispersions of PbSe and CdSe quantum dots.
abstract: We show by cryogenic transmission electron microscopy that PbSe and CdSe nanocrystals of various shapes in a liquid colloidal dispersion self-assemble into equilibrium structures that have a pronounced dipolar character, to an extent that depends on particle concentration and size. Analyzing the cluster-size distributions with a one-dimensional (1D) aggregation model yields a dipolar pair attraction of 8-10 kBT at room temperature. This accounts for the long-range alignment of the crystal planes of individual nanocrystals in self-assembled superstructures and for anisotropic nanostructures grown via oriented attachment.
authors: Van 't Hoff Laboratory for Physical and Colloid Chemistry, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
authors: Mark
authors: M
authors: Klokkenburg
authors: Arjan J
authors: AJ
authors: Houtepen
authors: Rolf
authors: R
authors: Koole
authors: Julius W J
authors: JW
authors: de Folter
authors: Ben H
authors: BH
authors: Erné
authors: Ernst
authors: E
authors: van Faassen
authors: Daniël
authors: D
authors: Vanmaekelbergh
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D003102:Colloids / Q000737:chemistry*; D003460:Crystallization / Q000379:methods*; D007854:Lead / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D019187:Cadmium Compounds; D003102:Colloids; D046911:Macromolecular Substances; D018036:Selenium Compounds; C088065:lead selenide; D007854:Lead; C058667:cadmium selenide