Li Gang, Gan Zhanhui, Liu Yuchu, Wang Shuai, Guo Qing-Yun, Liu Zhongguo, Tan Rui, Zhou Dongdong, Kong Deyu, Wen Tao, Dong Xue-Hui
South China Advanced Institute for Soft Matter Science and Technology, School of Molecular Science and Engineering, South China University of Technology, Guangzhou 510640, China.
Department of Polymer Science, The University of Akron, Akron, Ohio 44325, United States.
ACS Nano. 2020 Oct 27;14(10):13816-13823. doi: 10.1021/acsnano.0c06189. Epub 2020 Sep 23.
Anisotropic patchy particles with molecular precision are exquisite building blocks for constructing diverse meso-structures of high complexity. In this research, a library of molecular patchy clusters consisting of a collection of functional polyhedral oligomeric silsesquioxane cages with exact regio-configuration and composition were prepared through a robust and modular approach. By meticulously tuning the composition, molecular symmetry, and other parameters, these patchy clusters could assemble into diverse nanostructures, including unconventional complex spherical phases (., Frank-Kasper σ phase and dodecagonal quasicrystalline phase). As the size of the hydrophilic patch expands, a transition sequence from disorder to hexagonally packed cylinders and then to double gyroids was recorded, corresponding to a progressive decrease of interfacial curvature. On the other hand, regioisomers with the same composition but different regio-configuration adopt similar molecular packing but varied phase stability, as a result of the local self-sorting process to alleviate excess unfavorable interfacial contact. These precisely defined molecular patchy clusters provide a model system for a general understanding of the hierarchical structure formation and evolution based on anisotropic spherical building blocks at the nanoscale.
具有分子精度的各向异性补丁状颗粒是构建各种高复杂性介观结构的精美构建块。在本研究中，通过一种稳健且模块化的方法，制备了一个由一系列具有精确区域构型和组成的功能性多面体低聚倍半硅氧烷笼组成的分子补丁状簇库。通过精心调整组成、分子对称性和其他参数，这些补丁状簇可以组装成各种纳米结构，包括非常规的复杂球形相（如Frank-Kasper σ相和十二边形准晶相）。随着亲水性补丁尺寸的扩大，记录到从无序到六方堆积圆柱再到双螺旋体的转变序列，这对应于界面曲率的逐渐减小。另一方面，具有相同组成但不同区域构型的区域异构体由于局部自分类过程以减轻过多不利的界面接触，采用相似的分子堆积但具有不同的相稳定性。这些精确界定的分子补丁状簇为在纳米尺度上基于各向异性球形构建块全面理解层次结构的形成和演化提供了一个模型系统。
