Excellent electro-optical (E-O) performances are essential for high-quality reflective cholesteric liquid crystal (LC) displays, but are often limited by the high driving voltages required by these displays. Dispe...Excellent electro-optical (E-O) performances are essential for high-quality reflective cholesteric liquid crystal (LC) displays, but are often limited by the high driving voltages required by these displays. Dispersing functional nanomaterials into the LCs has emerged as a promising approach to achieve outstanding E-O properties. In this work, we report the facet-controlled E-O properties of a chiral nematic LC (N*LC) doped with cubic, octahedral, and rhornbic dodecahedral Cu20. The outstanding E-O properties of the doped systems are related to the interaction between the liquid crystals and Cu20 dopants with different exposed crystal planes. Doping with octahedral and rhombic dodecahedral Cu20 reduces the stability of the planar state, as a result of both the surface abundance of active Cu atoms that interact with the polarized LC molecules, and the large amounts of vertexes and edges on the crystal surfaces, which accelerate the transition from the planar to the focal conic state under an applied electric field. Rhombic Cu20 is the most effective dopant for improving the E-O properties of the present LCs, resulting in a 65.31% reduction of the threshold voltage. The facet and morphology effects highlighted in this work provide a new pathway to develop excellent energy-saving meso-materials with exposed high-reactivity facets, improving their potential applications in electro-optical technologies and information displays.展开更多
基金This work was mainly supported by National Basic Research Program of China (No.2014CB931802),the Major Project of International Cooperation of the Ministry of Science and Technology (No.2013DFB50340),National Natural Science Foundations of China (Nos.51272012,21471013,51532001,51333001,51173003,51402006 and 51303007),the Major Program of Chinese Ministry of Education (No.313002),the Beijing Natural Science Foundation (No.2163052) and China Postdoctoral Science Foundation Funded Project (No.2015M570916).
文摘Excellent electro-optical (E-O) performances are essential for high-quality reflective cholesteric liquid crystal (LC) displays, but are often limited by the high driving voltages required by these displays. Dispersing functional nanomaterials into the LCs has emerged as a promising approach to achieve outstanding E-O properties. In this work, we report the facet-controlled E-O properties of a chiral nematic LC (N*LC) doped with cubic, octahedral, and rhornbic dodecahedral Cu20. The outstanding E-O properties of the doped systems are related to the interaction between the liquid crystals and Cu20 dopants with different exposed crystal planes. Doping with octahedral and rhombic dodecahedral Cu20 reduces the stability of the planar state, as a result of both the surface abundance of active Cu atoms that interact with the polarized LC molecules, and the large amounts of vertexes and edges on the crystal surfaces, which accelerate the transition from the planar to the focal conic state under an applied electric field. Rhombic Cu20 is the most effective dopant for improving the E-O properties of the present LCs, resulting in a 65.31% reduction of the threshold voltage. The facet and morphology effects highlighted in this work provide a new pathway to develop excellent energy-saving meso-materials with exposed high-reactivity facets, improving their potential applications in electro-optical technologies and information displays.