Hybrid Nanocrystals of Small Molecules and Chemically Disordered Polymers
Hybrid Nanocrystals of Small Molecules and Chemically Disordered Polymers
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DOI：
10.1021/acsnano.2c00266
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发表时间：
2022-05-19
期刊：
影响因子：
17.1
通讯作者：
Stupp, Samuel I.
中科院分区：
文献类型：
--
作者：
Bruckner, Eric P.;Curk, Tine;Stupp, Samuel I.
由小分子形成的有机晶体可以是高度功能性的，但通常是脆性或不溶性结构，使用或从液相加工的可能性有限。一个可能的解决方案是将聚合物纳米级集成到有机晶体中，而不牺牲长程有序性和功能。这使得有机晶体能够受益于聚合物组分的有利的机械和化学性质。我们在这里报告的策略，其中小分子共结晶与化学无序聚合物的侧链，以创建混合纳米结构包含一个高度有序的晶格。同步辐射X射线散射，吸收光谱，和粗粒分子动力学模拟表明，聚合物主链形成？？外晶？一层无序的链缠绕在纳米结构上，成为有趣特性的把手。它的形态学？混合粘合聚合物？纳米结构是由聚合物之间的竞争？熵和晶格的焓，允许通过改变聚合物整合的程度来控制晶格的纵横比。我们观察到，具有聚合物外晶层的纳米结构表现出增强的断裂强度、自修复能力和在水中的分散性，这有利于它们作为太阳能电池中的光捕获组件的使用。在计算的指导下，未来的工作可以进一步探索这些混合纳米结构作为功能材料的组件。
Organic crystals formed by smal l molecules can be highly functional but are often brittle or insoluble structures with limited possibilities for use or processing from a liquid phase. A possible solution is the nanoscale integration of polymers into organic crystals without sacrificing long-range order and therefore function. This enables the organic crystals to benefit from the advantageous mechanical and chemical properties of the polymeric component. We report here on a strategy in which smal l molecules cocrystallize with side chains of chemically disordered polymers to create hybrid nanostructures containing a highly ordered lattice. Synchrotron X-ray scattering, absorption spectroscopy, and coarse-grained molecula r dynamics simulations reveal that the polymer backbones form an ???exo-crystalline??? layer of disordered chains that wrap around the nanostructures, becoming a handle for interesting properties. The morphology of this ???hybrid bonding polymer??? nanostructure is dictated by the competition between the polymers??? entropy and the enthalpy of the lattice allowing for control over the aspect ratio of the nanocrystal by changing the degree of polymer integration. We observed that nanostructures with an exo-crystalline layer of polymer exhibit enhanced fracture strength, self-healing capacity, and dispersion in water, which benefits their use as light-harvesting assemblies in photocatalysis. Guided by computation, future work could furthe r explore these hybrid nanostructures as components for functional materials.