作者：Jinlan Li, Xuejie Liu, Jing Jin, Nan Yan, Wei Jiang
关键字：金纳米立方体, 二维单层超晶格, 溶剂退火, 自组装, 表面增强拉曼散射
论文来源：期刊
具体来源：Nanotechnology, 2022, 33(38), 385601
发表时间：2022年

摘要：金属纳米晶体自发自组装成具有高度有序对称性和构型的二维（2D）单层超晶格，为功能材料制造铺平了道路。然而，由于取向和构型一致性要求，各向异性纳米晶体自组装成高质量超晶格仍面临巨大挑战。本文首次开发了一种简便而通用的溶剂退火驱动二维界面组装方法，利用合成的干燥金属纳米晶体，实现具有可调粒子间距和内部构型（面对面和六角排列）的非密排2D单层金纳米立方体（AuNC）超晶格的构建，通过精确控制AuNC上接枝聚合物配体分子量和相邻AuNC间范德华力实现。此外，生成的高度有序内部排列和取向的2D单层AuNC超晶格尺寸可达数百微米，由于强等离激元耦合效应，大规模超晶格具有显著表面增强拉曼散射性能。该策略不仅为制造纳米晶体超晶格结构提供了稳健途径，也为构建功能纳米器件提供了有前景的平台。

Abstract：The spontaneous self-assembly of metal nanocrystals into two-dimensional (2D) monolayer superlattices with highly ordered symmetry and configuration paves the way towards the fabrication of functional materials. However, there remains great challenge for anisotropic nanocrystals to self-assemble into high quality superlattice because of the orientation and configuration consistency. Here, a facile yet universal solvent annealing driven 2D interfacial assembly of synthetic dried metal nanocrystals is firstly developed to realize the construction of the non-close-packing 2D monolayer gold nanocube (AuNC) superlattice with tunable interparticle distance and internal configurations (i.e. face-to-face and hexagonally-packed arrangement), which is achieved by precisely controlling molecular weight of polymer ligands tethered on AuNCs and the van der Waals forces between the adjacent AuNCs. In addition, the scale of the generated 2D monolayer AuNC superlattice with highly ordered internal arrangement and orientation can reach up to hundreds of micrometers, thus acquiring significant surface-enhanced Raman scattering performance of the large scale superlattice due to the strong plasma coupling effect. This strategy not only provides a robust route to fabricate nanocrystal superlattice structures but also offers a promising platform for constructing functional nanodevices.

论文链接：https://doi.org/10.1088/1361-6528/ac7812