Self-Assembly in Size-Disperse Binary Systems

Binary systems of nanoparticles are promising targets for self-assembled materials due to their great potential for structural diversity (compared with one-component systems). Hard particle models often fail to capture the phase behavior of binary systems [1]. Previously, the effect of particle size dispersity on structural stability has been examined almost exclusively in nanosphere and disk phases, with only a few studies investigating particles with, e.g., diverse anisotropic properties [2,3]. We investigate molecular dynamics simulations of binary systems of particles interacting via attractive isotropic potentials that assemble structures of various symmetries and complexities. We report different crystal phases that are more or less sensitive to the introduction of differently-sized particles, and we discuss the use of this study to predict robust systems for improved self-assembly experiments on the mesoscale.

References:

[1] X. Ye, C. Zhu, P. Ercius, S. N. Raja, B. He, M. R. Jones, M. R. Hauwiller, Y. Liu, T. Xu, A. P. Alivisatos, "Structural diversity in binary superlattices self-assembled from polymer-grafted nanocrystals", Nat. Commun. 6, 10052 (2015).

[2] C. L. Phillips, C. R. Iacovella, S. C. Glotzer, "Stability of the double gyroid phase to nanoparticle polydispersity in polymer-tethered nanosphere systems", Soft Matter 6, 1693-1703 (2010).

[3] C. L. Phillips, S. C. Glotzer, "Effect of nanoparticle polydispersity on the self-assembly of polymer tethered nanospheres", J. Chem. Phys. 137, 104901 (2012).