title: Self-assembly of colloidal hexagonal bipyramid- and bifrustum-shaped ZnS nanocrystals into two-dimensional superstructures.
abstract: We present a combined experimental, theoretical, and simulation study on the self-assembly of colloidal hexagonal bipyramid- and hexagonal bifrustum-shaped ZnS nanocrystals (NCs) into two-dimensional superlattices. The simulated NC superstructures are in good agreement with the experimental ones. This shows that the self-assembly process is primarily driven by minimization of the interfacial free-energies and maximization of the packing density. Our study shows that a small truncation of the hexagonal bipyramids is sufficient to change the symmetry of the resulting superlattice from hexagonal to tetragonal, highlighting the crucial importance of precise shape control in the fabrication of functional metamaterials by self-assembly of colloidal NCs.
authors.affiliation: Condensed Matter and Interfaces and §Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University , 3508 TA Utrecht, The Netherlands.
authors.forename: Ward
authors.initials: W
authors.lastname: van der Stam
authors.forename: Anjan P
authors.initials: AP
authors.lastname: Gantapara
authors.forename: Quinten A
authors.initials: QA
authors.lastname: Akkerman
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Soligno
authors.forename: Johannes D
authors.initials: JD
authors.lastname: Meeldijk
authors.forename: René
authors.initials: R
authors.lastname: van Roij
authors.forename: Marjolein
authors.initials: M
authors.lastname: Dijkstra
authors.forename: Celso
authors.initials: C
authors.lastname: de Mello Donega