Nature Commun. 6, 10052 (2015)

Credit: NPG

The potential functional applications of multicomponent nanocrystal superlattices depend largely upon the level of control that can be achieved through the combination of their constituent building blocks. Although it is possible to control lattice structure by modifying the chemical/structural arrangements of the individual crystals, or through ligand attachment, it can still be difficult to achieve stable and larger-scale nanocrystal lattices. Ting Xu, A. Paul Alivisatos and their colleagues now present a method for the controllable formation of long-range-ordered two- and three-dimensional binary nanocrystal superlattices. Their structures were composed of spherical nanocrystals modified on their surface with polymeric ligands. They found that these surface polymers offered significant benefits for the stabilization of precise (and large) interparticle separations. By tailoring the sizes of the nanocrystals and the appended polymers, the researchers were able to generate a variety of well-ordered superlattices over different length scales.