Institute of Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich 8093, Switzerland.
Instituto de Ciencia Molecular (ICMol), Universidad de Valencia, c/Catedrático José Beltrán, 2, 46980 Paterna, Spain.
J Am Chem Soc. 2020 May 20;142(20):9372-9381. doi: 10.1021/jacs.0c01935. Epub 2020 Apr 28.
Controlling and understanding the mechanisms that harness crystallization processes is of utmost importance in contemporary materials science and, in particular, in the realm of reticular solids where it still remains a great challenge. In this work, we show that environments mimicking microgravity conditions can harness the size and shape of functional biogenic crystals such as peptide-based metal-organic frameworks (MOFs). In particular, we demonstrate formation of the largest single crystals with controlled nonequilibrium shapes of peptide-based MOFs reported to date (e.g., those featuring curved crystal habits), as opposed to the typical polyhedral microcrystals obtained under bulk crystallization conditions. Such unique nonequilibrium morphologies arise from the interplay between the diffusion-controlled supply of precursors in simulated microgravity environments and the physical constraints imposed during crystal growth. In fact, our method mimics two main strategies of morphogenesis in biomineralization, i.e., spatial and morphological control, both being largely unexplored in the field of self-assembled functional materials. The presented results may open new opportunities to study and understand fundamental questions of relevance to materials science, such as how the size and shape of artificial crystals can influence their properties and functions while providing a strategy to tailor the size and shape of peptide-based MOF single crystals to specific applications.
控制和理解利用结晶过程的机制在当代材料科学中至关重要，特别是在网状固体领域，这仍然是一个巨大的挑战。在这项工作中，我们表明，模拟微重力条件的环境可以利用功能生物晶体的大小和形状，例如基于肽的金属有机骨架（MOFs）。特别是，我们展示了迄今为止报道的基于肽的 MOFs 的最大单晶的形成，其具有受控的非平衡形状（例如，具有弯曲晶体习性的那些），而不是在体相结晶条件下获得的典型多面体微晶。这种独特的非平衡形态源于在模拟微重力环境中前驱体的扩散控制供应与晶体生长过程中施加的物理限制之间的相互作用。事实上，我们的方法模拟了生物矿化中两种主要的形态发生策略，即空间控制和形态控制，这两者在自组装功能材料领域都很大程度上尚未得到探索。所提出的结果可能为研究和理解与材料科学相关的基本问题提供新的机会，例如人工晶体的大小和形状如何影响它们的性质和功能，同时为基于肽的 MOF 单晶的大小和形状提供特定应用的定制策略。
