Azobenzene Lyotropic Liquid Crystals as Photoswitchable Materials for Solar Thermal Fuels

本项目将首次探索偶氮苯-光表面活性剂(AzoPS)的溶致液晶(LLC)组装作为高储能STF的机会。最近的研究表明，中性AzoPS可以形成各种LLC相，通过策略性的分子结构设计，可以在低浓度(10wt%)下获得这些LLC相。LLC中间相可在紫外光照射下被破坏，并在蓝光(或热)下重新组装。由于分子间相互作用的增强和生色团密度的提高，AzoPS LLC可以为STF提供更高的储能密度。重点将是确定储能密度。为了了解这种新的材料设计空间，该项目将通过使用不同的LLC中间相、与常规表面活性剂的共稀释和溶剂来调整分子堆积。组合的结构、光谱和热表征将用于将光开关状态的变化与结构堆积和储能密度相关联。利用小角X射线散射(SAXS)和红外光谱来研究AzoPS LLC中光异构化的异质性、动力学和能量学，以设计具有高储能密度的系统。

This project will investigate the opportunity for lyotropic liquid crystal (LLC) assemblies of azobenzene-photosurfactants (AzoPS) as high energy storage STFs for the first time. It has recently been shown that neutral AzoPS form a variety of LLC phases, which can be accessed at low concentrations (10 wt%) through strategic design of the molecular structure. The LLC mesophases could be destroyed upon UV irradiation and re-assembled under blue light (or heat). The AzoPS LLCs could offer enhanced energy storage density for STFs due to the combination of increased intermolecular interactions and a high chromophore density. The key focus will be to determine the energy storage density. To understand this new material design space, the project will tune molecular packing by using: different LLC mesophases, co-dilution with a regular surfactant, and solvent.Combined structural, spectroscopy and thermal characterisation will be used to correlate changes in the photoswitch state, to structural packing and the energy storage density. Attention will be paid to understanding the heterogeneity, kinetics and energetics of photoisomerisation in AzoPS LLCs using small-angle X-ray scattering (SAXS) and infrared spectroscopy to design system with high energy storage density.