西班牙巴塞罗那大学Josep Puigmartí-Luis团队的最新研究，揭示了利用反应扩散条件触发MOF生长过程中的路径复杂性。 相关研究成果于2021年3月17日发表在《德国应用化学》。

配位聚合物（CPs），包括金属有机骨架（MOFs），是一种在电子学、磁学、催化和气体存储/分离等领域有着广阔应用前景的晶体材料。然而，其形成机制和途径基本上还不清楚。

该文中，研究人员证明了在结晶过程的早期阶段（即40 ms内），通过使用连续流动微流控装置实现的试剂扩散控制混合，可用于实现原型自旋交叉MOF向其热力学产物的新型结晶路径。特别是在微流控混合条件下触发结晶时，实验观察到了两条不同且前所未有的成核-生长路径。

全原子分子动力学模拟也证实了晶体生长过程中这两条不同路径的发生。与此形成鲜明对比的是，在体（湍流）混合条件下观察到颗粒附着结晶。

这些史无前例的结果为理解CPs的生长提供了良好的基础，并为利用非平衡条件进行多孔材料工程开辟了新的途径。

附：英文原文

Title: Exploiting reaction‐diffusion conditions to trigger pathway complexity in the growth of a MOF

Author: Josep Puigmartí, N, Afshin Abrishamkar, Alessandro Sorrenti, Lorenzo Di Rienzo, Mauro Satta, Marco DAbramo, Eugenio Coronado, Andrew J. deMello, Guillermo Mí

Issue&Volume: 2021-03-17

Abstract: Coordination polymers (CPs), including metal‐organic frameworks (MOFs), are crystalline materials with promising applications in electronics, magnetism, catalysis, and gas storage/separation. However, the mechanisms and pathways underlying their formation remain largely undisclosed. Herein, we demonstrate that diffusion‐controlled mixing of reagents at the very early stages of the crystallization process (i.e., within 40 ms), achieved by using continuous‐flow microfluidic devices, can be used to enable novel crystallization pathways of a prototypical spin‐crossover MOF towards its thermodynamic product. In particular, two distinct and unprecedented nucleation‐growth pathways were experimentally observed when crystallization was triggered under microfluidic mixing. Full‐atom molecular dynamics simulations also confirm the occurrence of these two distinct pathways during crystal growth. In sharp contrast, a crystallization by particle attachment was observed under bulk (turbulent) mixing. These unprecedented results provide a sound basis for understanding the growth of CPs and open up new avenues for the engineering of porous materials by using out‐of‐equilibrium conditions.

DOI: 10.1002/anie.202101611

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202101611