Crystallization Kinetics of a Liquid-Forming 2D Coordination Polymer
Crystallization Kinetics of a Liquid-Forming 2D Coordination Polymer
复制标题
液态形成的二维配位聚合物的结晶动力学
DOI：
10.1021/acs.nanolett.2c03207
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发表时间：
2022
期刊：
影响因子：
10.8
通讯作者：
Horike Satoshi
中科院分区：
文献类型：
--
作者：
Das Chinmoy;Nishiguchi Taichi;Fan Zeyu;Horike Satoshi
研究了二维配位聚合物[Ag2(L1)(CF3SO3)2] （1,l1 = 4,4′-联苯二腈）在加热-冷却过程中的结晶熔化机理和结晶行为。结晶在282℃时熔融，随后的温和冷却导致242℃时突然结晶，DSC证实了这一点。通过量热、光谱和机械测量，讨论了温度相关的结构变化。他们发现，在熔体状态下，配位键网络部分保留，但熔体的粘度明显较低，为9.8 × 10-2Pa·s atTm，比ZIF-62 atTm（435℃）低6个数量级。流变学研究提供了对再结晶过程的快速弛豫动力学的理解，以及hightm为成核提供了足够的热能来跨越活化能垒。利用Avrami方程，通过量热法测定等温结晶动力学，确定了核的性质及其晶体生长机理。
We investigated a mechanism of crystal melting and crystallization behavior of a two-dimensional coordination polymer [Ag2(L1)(CF3SO3)2] (1, L1 = 4,4′-biphenyldicarbonitrile) upon heating-cooling processes. The crystal showed melting at 282 °C, and the following gentle cooling induced the abrupt crystallization at 242 °C confirmed by DSC. A temperature-dependent structural change has been discussed through calorimetric, spectroscopic, and mechanical measurements. They indicated that the coordination-bond networks are partially retained in the melt state, but the melt showed a significantly low viscosity of 9.8 × 10–2Pa·s atTmwhich is six orders lower than that of ZIF-62 atTm(435 °C). Rheological studies provided an understanding of the fast relaxation dynamics for the recrystallization process, along with that the highTmprovides enough thermal energy to crossover the activation energy barrier for the nucleation. The isothermal crystallization kinetics through calorimetric measurements with applying the Avrami equation identified the nature of the nuclei and its crystal growth mechanism.