Dynamics of N-H—N hydrogen bond in Flexible Organic Ferroelectrics Using QENS and MD simulations

Sustainable and flexible functional materials are important candidates of current research, because of their potential applications in plastic electronics. Metal free organic ferroelectrics are one of such materials having applications in data and storage devices. Since flexibility and ferroelectricity are rare combinations, organic ferroelectrics are candidates of intense research promising of designing new ferroelectrics. Dynamics of hydrogens have important contributions in the performance of these organic ferroelectrics. To build on our previous investigations on hydrogen bonded organic ferroelectrics, in this proposal I propose to investigate dynamics of imidazole based ferroelectrics, MBI. Selective hydrogen ions will be deuterated partially to separate out the N-H—N bond dynamics using QENS experiments. This hydrogen bond dynamics will be correlated with ferroelectricity through MD simulations to investigate effect of N-H—N motions in organic-ferroelectrics for generating useful knowledge of ferroelectricity in organic materials.

可持续且柔性的功能材料是当前研究的重要候选方向，因其在塑料电子领域具备潜在应用价值。无金属有机铁电材料便是这类可应用于数据存储器件的材料之一。由于柔性与铁电性实属罕见的性能组合，有机铁电材料成为当前备受关注的研究热点，有望助力新型铁电材料的设计开发。氢原子动力学过程对这类有机铁电材料的性能有着至关重要的影响。为延续此前针对氢键型有机铁电材料的研究基础，本提案拟开展咪唑基铁电材料MBI的动力学特性研究。具体而言，将通过对部分选择性氢原子进行氘代处理，结合准弹性中子散射（Quasielastic Neutron Scattering, QENS）实验，分离出N-H—N键的动力学过程。本研究将通过分子动力学（Molecular Dynamics, MD）模拟，将此类氢键动力学过程与铁电性相关联，以探究N-H—N键运动对有机铁电材料的影响，从而为有机材料中铁电性的相关研究提供具有实用价值的理论认知。