熵驱动无机纳米棒液晶态自组装

Entropy-driven liquid crystalline self-assembly of inorganic nanorods

针对有机液晶材料在实际应用中存在热稳定性不足和温度区间较窄等问题,结合快速发展的纳米材料合成及组装技术,发挥无机纳米材料富电子、高热稳定的特点,发展新型无机液晶态材料是目前一个热点研究领域。本文从归纳液晶态组装所蕴含的相变规律及调控机理出发,包括Onsager硬棒理论、DLVO理论、胶体系统中的熵作用(如排空吸引和位阻排斥),系统地综述了近年来以熵为主要驱动力的无机液晶态组装的研究进展。进而,以理想的组装单元之一——金纳米棒为例,深入讨论了组装方法、颗粒间相互作用对调控组装结构的影响规律,并例举了所得组装体在光电子器件中的潜在应用。最后,通过总结组装技术用以制备无机液晶态材料仍存在的问题,给出可能的解决方案并对未来的发展方向进行了展望。

Owing to the existing issues of poor thermal stability and narrow temperature interval in applications of organic liquid crystal materials,developing novel inorganic liquid crystal is an alternative strategy due to the virtues of electron-rich characteristics and high thermal stability of the well-developed inorganic nanomaterials.Starting from the summarization of the phase transition rules and the regulation mechanisms of liquid crystalline self-assembly,including Onsager theory,DLVO theory,and entropy effects on depletion attraction and steric repulsion,this review demonstrates recent progress in entropy-driven liquid crystalline self-assembly of the inorganic nanomaterials.Taking the ideal building block of gold nanorods as an example,the regulations of the advanced self-assembly methods and the interactions between the nanorods on the diverse assembly structures are discussed,and their potential applications in optoelectronic devices are illustrated.Finally,future developments are prospected aiming at the problems in preparing inorganic liquid crystal materials using the self-assembly technology.