In situ study of the formation mechanism of two-dimensional superlattices from PbSe nanocrystals

J. J. Geuchies, C. Van Overbeek, W.H. Evers, B. Goris, A. De Backer, A.P. Gantapara, F.T. Rabouw, J. Hilhorst, J.L. Peters, O. Konovalov, A.V. Petukhov, M. Dijkstra, L.D.A. Siebbeles, S. Van Aert, S. Bals, D. Vanmaekelbergh

Onderzoeksoutput: Bijdrage aan tijdschriftTijdschriftartikelAcademicpeer review

103 Citaten (Scopus)


Oriented attachment of PbSe nanocubes can result in the formation of two-dimensional (2D) superstructures with long-range nanoscale and atomic order. This questions the applicability of classic models in which the superlattice grows by first forming a nucleus, followed by sequential irreversible attachment of nanocrystals, as one misaligned attachment would disrupt the 2D order beyond repair. Here, we demonstrate the formation mechanism of 2D PbSe superstructures with square geometry by using in situ grazing-incidence X-ray scattering (small angle and wide angle), ex situ electron microscopy, and Monte Carlo simulations. We observed nanocrystal adsorption at the liquid/gas interface, followed by the formation of a hexagonal nanocrystal monolayer. The hexagonal geometry transforms gradually through a pseudo-hexagonal phase into a phase with square order, driven by attractive interactions between the {100} planes perpendicular to the liquid substrate, which maximize facet-to-facet overlap. The nanocrystals then attach atomically via a necking process, resulting in 2D square superlattices.

Originele taal-2Engels
Pagina's (van-tot)1248-1254
Aantal pagina's7
TijdschriftNature Materials
Nummer van het tijdschrift12
StatusGepubliceerd - 1 dec 2016


Citeer dit

Geuchies, J. J., Van Overbeek, C., Evers, W. H., Goris, B., De Backer, A., Gantapara, A. P., ... Vanmaekelbergh, D. (2016). In situ study of the formation mechanism of two-dimensional superlattices from PbSe nanocrystals. Nature Materials, 15(12), 1248-1254.