title: Structural diversity in binary superlattices self-assembled from polymer-grafted nanocrystals.
abstract: Multicomponent nanocrystal superlattices represent an interesting class of material that derives emergent properties from mesoscale structure, yet their programmability can be limited by the alkyl-chain-based ligands decorating the surfaces of the constituent nanocrystals. Polymeric ligands offer distinct advantages, as they allow for more precise tuning of the effective size and 'interaction softness' through changes to the polymer's molecular weight, chemical nature, architecture, persistence length and surrounding solvent. Here we show the formation of 10 different binary nanocrystal superlattices (BNSLs) with both two- and three-dimensional order through independent adjustment of the core size of spherical nanocrystals and the molecular weight of densely grafted polystyrene ligands. These polymer-brush-based ligands introduce new energetic contributions to the interparticle potential that stabilizes various BNSL phases across a range of length scales and interparticle spacings. Our study opens the door for nanocrystals to become modular elements in the design of functional particle brush solids with controlled nanoscale interfaces and mesostructures.
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors.forename: Xingchen
authors.initials: X
authors.lastname: Ye
authors.affiliation: Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Chenhui
authors.initials: C
authors.lastname: Zhu
authors.affiliation: National Center for Electron Microscopy, The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Peter
authors.identifier: http://orcid.org/0000-0002-6762-9976
authors.initials: P
authors.lastname: Ercius
authors.affiliation: Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.|Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Shilpa N
authors.initials: SN
authors.lastname: Raja
authors.affiliation: The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Bo
authors.initials: B
authors.lastname: He
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Jones
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Hauwiller
authors.affiliation: The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.|Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Ting
authors.initials: T
authors.lastname: Xu
authors.affiliation: Department of Chemistry, University of California, Berkeley, California 94720, USA.|Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.|Kavli Energy NanoScience Institute, Berkeley, California 94720, USA.
authors.forename: A Paul
authors.initials: AP
authors.lastname: Alivisatos