Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
Department of Chemistry, Columbia University, New York, NY, 10027, USA.
Nat Commun. 2018 Sep 24;9(1):3871. doi: 10.1038/s41467-018-06395-8.
The ability to modulate nanoparticle (NP) assemblies with atomic precision is still lacking, which hinders us from creating hierarchical NP organizations with desired properties. In this work, a hierarchical fibrous (1D to 3D) assembly of Au NPs (21-gold atom, Au) is realized and further modulated with atomic precision via site-specific tailoring of the surface hook (composed of four phenyl-containing ligands with a counteranion). Interestingly, tailoring of the associated counterion significantly changes the electrical transport properties of the NP-assembled solids by two orders of magnitude due to the altered configuration of the interacting π-π pairs of the surface hooks. Overall, our success in atomic-level modulation of the hierarchical NP assembly directly evidences how the NP ligands and associated counterions can function to guide the 1D, 2D, and 3D hierarchical self-assembly of NPs in a delicate manner. This work expands nanochemists' skills in rationally programming the hierarchical NP assemblies with controllable structures and properties.
目前，我们仍然缺乏对纳米粒子（NP）组装体进行原子精度调控的能力，这限制了我们创造具有所需性质的分层 NP 组织。在这项工作中，实现了金纳米粒子（Au）的分级纤维状（1D 至 3D）组装体，并通过对表面钩（由四个含苯基的配体和抗衡阴离子组成）进行特定位置的修饰，进一步实现了原子精度的调控。有趣的是，由于表面钩相互作用的π-π 对的构型发生改变，相关抗衡离子的修饰显著改变了 NP 组装固体的电输运性质，变化幅度达到两个数量级。总的来说，我们在原子级调控分层 NP 组装体方面的成功直接证明了 NP 配体和相关抗衡离子如何能够以精细的方式引导 NP 的 1D、2D 和 3D 分层自组装。这项工作扩展了纳米化学家在具有可控结构和性能的层次 NP 组装体上进行合理编程的技能。
