近日，研究院刘雪杰博士在纳米科学领域顶级期刊Nano Letters（自然指数期刊，中科院一区TOP，影响因子10.8），发表了题为“Polyhedral Colloidal Clusters Assembled from Amphiphilic Nanoparticles in Deformable Droplets)”的研究论文。该论文第一作者为刘雪杰博士，通讯作者为中国科学院长春应用化学研究所姜伟研究员。

如何实现纳米粒子内部排列和外部形态的同时可控是纳米技术领域的关键问题。本论文提出了一种通过触发乳液液滴界面变形构筑多面体超晶格的新方法。实验结果表明，表面活性剂浓度和纳米粒子组装基元亲疏水性是影响液滴界面变形程度的关键因素，也是组装体的结构和形态的决定因素。研究发现，增加纳米粒子组装基元的亲水性，基元更倾向于迁移到液滴界面上。在表面活性剂分子和组装基元的协同作用下，界面张力得到进一步降低，液滴界面变形程度更加明显，组装体从麦凯二十面体转变为正四面体面心立方超晶格。此外，通过记录不同挥发阶段的液滴形态，实验还揭示了正四面体超晶格的动力学过程和形成机理。该研究结果为设计纳米粒子组装体的结构和形态提供了一种新的策略，为制备相关性功能器件提供了重要途径。

Fig.1 Clusters assembled from the AuNPs@PS/P2VP building blocks with a P2VP to PS grafting ratio of 5:5 in emulsion droplets for different concentrations of surfactant CTAB and molecule weights of PS. (A) SEM image of Mackay icosahedral clusters for 4 mg/mL CTAB content and PS_2k; (B-C) TEM and TEMT reconstruction image of Mackay icosahedral clusters, respectively；(D) Variation of the interfacial tension between chloroform and water withdifferent CTAB concentrations, and the corresponding SEM imagesof the colloidal clustersfor PS_2k；The scale bars for all SEM images are 100 nm；(E-F) SEM images of colloidal clusters assembled from AuNPs@PS/P2VP building blocks with PS_5kand PS_12kat 4 mg/mL CTAB (γ= 6.4 mN/m)，respectively.

Fig.2 Clusters assembled fromthe AuNPs@PS/P2VP building blocks with different grafting ratios of P2VP to PS for 1 mg/mL CTAB (γ= 10.2 mN/m) and PS_2k. (A-D) SEM, TEM and TEMT reconstruction image of the regular tetrahedral cluster at a ratioof P2VP to PSof 8:2, respectively; (E) SAXS pattern and magnified TEM image of a regular tetrahedral cluster; (F-H) SEM images of colloidal clusters self-assembled from the AuNPs@PS/P2VP building blocks at various ratios of P2VP to PS (F: 5:5, G: 6:4, and H: 8:2).

该研究成果得到了国家自然科学基金和国家重点研发展计划的大力支持。

论文DOI (https://doi.org/10.1021/acs.nanolett.3c01995)