Lyu Dengping, Xu Wei, Payong Jae Elise L, Zhang Tianran, Wang Yufeng
Department of Chemistry, The University of Hong Kong, Pokfulam Road, 999077, Hong Kong SAR, China.
Nat Commun. 2022 Jul 9;13(1):3980. doi: 10.1038/s41467-022-31651-3.
Assembling metal-organic framework (MOF)-based particles is an emerging approach for creating colloidal superstructures and hierarchical functional materials. However, realization of this goal requires strategies that not only regulate particle interactions but also harness the anisotropic morphologies and functions of various frameworks. Here, by exploiting depletion interaction induced by ionic amphiphiles, we show the assembly of a broad range of low-dimensional MOF colloidal superstructures, including 1D straight chains, alternating or bundled chains, 2D films of hexagonal, square, centered rectangular, and snowflake-like architectures, and quasi-3D supercrystals. With well-defined polyhedral shapes, the MOF particles are mutually oriented upon assembly, producing super-frameworks with hierarchically coordinated crystallinity and micropores. We demonstrate this advantage by creating functional MOF films with optical anisotropy, in our cases, birefringence and anisotropic fluorescence. Given the variety of MOFs available, our technique should allow access to advanced materials for sensing, optics, and photonics.
组装基于金属有机框架（MOF）的颗粒是一种用于创建胶体超结构和分级功能材料的新兴方法。然而，要实现这一目标，需要的策略不仅要调节颗粒间的相互作用，还要利用各种框架的各向异性形态和功能。在这里，通过利用离子型两亲物诱导的耗尽相互作用，我们展示了多种低维MOF胶体超结构的组装，包括一维直链、交替或束状链、二维六边形、正方形、中心矩形和雪花状结构的薄膜以及准三维超晶体。具有明确多面体形状的MOF颗粒在组装时相互取向，产生具有分级协调结晶度和微孔的超框架。我们通过创建具有光学各向异性（在我们的例子中为双折射和各向异性荧光）的功能性MOF薄膜来证明这一优势。鉴于现有MOF的多样性，我们的技术应该能够获得用于传感、光学和光子学的先进材料。
