Dipartimento di Fisica e Chimica, Viale delle Scienze, Ed. 17, 90128 Palermo, Italy.
ENEA, Laboratory SSPT-PROMAS-MATPRO, Rome 00123, Italy.
J Chem Phys. 2018 May 21;148(19):193816. doi: 10.1063/1.5016236.
Fluorinated Room Temperature Ionic Liquids (FRTILs) are a branch of ionic liquids that is the object of growing interest for a wide range of potential applications, due to the synergic combination of specifically ionic features and those properties that stem from fluorous tails. So far limited experimental work exists on the micro- and mesoscopic structural organization in this class of compounds. Such a work is however necessary to fully understand morphological details at atomistic level that would have strong implications in terms of bulk properties. Here we use the synergy between X-ray and neutron scattering together with molecular dynamics simulations to access structural details of a technologically relevant FRTIL that is characterised by an anion bearing a long enough fluorinated tail to develop specific morphological features. In particular, we find the first experimental evidence that in FRTILs bearing an asymmetric bis(perfluoroalkyl)sulfonyl-imide anion, fluorous side chains tend to be spatially segregated into nm-scale spatial heterogeneities. This feature together with the well-established micro-segregation of side alkyl chains in conventional RTILs leads to the concept of triphilic ILs, whose technological applications are yet to be fully developed.
氟化室温离子液体（FRTILs）是离子液体的一个分支，由于其特定的离子特性和源自氟尾的特性的协同组合，对于广泛的潜在应用，它正成为越来越多的关注对象。到目前为止，对于这类化合物的微观和介观结构组织，仅存在有限的实验工作。然而，这样的工作对于在原子水平上充分理解形态细节是必要的，这将对整体性质产生重大影响。在这里，我们使用 X 射线和中子散射与分子动力学模拟之间的协同作用来研究具有足够长氟尾以发展特定形态特征的技术相关 FRTIL 的结构细节。特别地，我们发现了第一个实验证据，即在具有不对称双（全氟烷基）磺酰亚胺阴离子的 FRTIL 中，氟侧链倾向于在纳米尺度上空间分离成空间异质结构。这种特征与传统 RTIL 中侧链烷基的良好微分离相结合，导致了三亲性离子液体的概念，其技术应用尚未得到充分开发。
