Ye Xingchen, Zhu Chenhui, Ercius Peter, Raja Shilpa N, He Bo, Jones Matthew R, Hauwiller Matthew R, Liu Yi, Xu Ting, Alivisatos A Paul
Department of Chemistry, University of California, Berkeley, California 94720, USA.
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Nat Commun. 2015 Dec 2;6:10052. doi: 10.1038/ncomms10052.
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.
多组分纳米晶体超晶格是一类有趣的材料，它从介观结构中获得新兴特性，然而其可编程性可能会受到修饰在组成纳米晶体表面的基于烷基链的配体的限制。聚合物配体具有明显优势，因为它们可以通过改变聚合物的分子量、化学性质、结构、持久长度和周围溶剂，更精确地调节有效尺寸和“相互作用柔软度”。在这里，我们展示了通过独立调节球形纳米晶体的核尺寸和密集接枝的聚苯乙烯配体的分子量，形成了10种具有二维和三维有序结构的不同二元纳米晶体超晶格（BNSL）。这些基于聚合物刷的配体为粒子间势能引入了新的能量贡献，从而在一系列长度尺度和粒子间距上稳定了各种BNSL相。我们的研究为纳米晶体成为具有可控纳米级界面和介观结构的功能性粒子刷固体设计中的模块化元素打开了大门。
