松果状纳米氧化铁对液晶电光性能的影响

doi:10.11944/j.issn.1000-0518.2019.05.180297

摘要/Abstract

摘要：

液晶材料被广泛应用于液晶显示器(LCD)中,但是由于液晶中杂质的存在,导致液晶的应用电压变大,增加了能耗。为了降低应用中的阈值电压和饱和电压,通常向液晶中添加纳米颗粒来提高电光性能。本文采用简单的化学沉淀法制备了形貌均一,大小尺寸均匀的松果状氧化铁(P-Fe₂O₃)纳米颗粒。将其掺杂到向列相液晶4-氰基-4'-戊基联苯(4-cyano-4'-pentylbiphenyl,5CB)中,结果表明,掺杂质量分数为0.5%时,电光性能达到最优,阈值电压和饱和电压分别降低24.8%和45.2%,对比度增大46%,响应时间降低至17.6 ms,此性能优于相同条件下掺杂普通Fe₂O₃纳米颗粒的向列相液晶5CB,其阈值电压和饱和电压分别降低15%和16%。这归因于松果状Fe₂O₃纳米颗粒可以在向列相液晶5CB中均匀分散,其粗糙的表面吸附了液晶中的杂质离子,减少了杂质离子的屏蔽效应,从而提高了电光性能。

关键词: 液晶显示器件, 半导体纳米材料, 松果状Fe₂O₃, 向列相液晶, 电光性能

Abstract:

Liquid crystal(LC) materials are widely used in LC displays(LCD). However, due to the presence of impurities in liquid crystal, the application voltage of liquid crystal becomes large, which results in the increase of energy consumption. In order to decrease the threshold voltage and saturation voltage, nanoparticles are usually added to LC to improve the electro-optical performance. In this paper, pinecone-like ferric oxide(P-Fe₂O₃) nanoparticles with uniform shape and size were prepared by a simple chemical precipitation method. Nematic liquid crystal 4-cyano-4'-pentylbiphenyl(5CB) is doped with pinecone-like Fe₂O₃ nanoparticles in different doping contents. The results show that the best electro-optical properties of the LC is achieved when the doping mass fraction is 0.5%. The threshold voltage and saturation voltage decrease by 24.8% and 45.2%, respectively, the contrast ratio increases by 46%, and the response time decreases to 17.6 ms. The property is superior to the ordinary Fe₂O₃ nanoparticles doped in 5CB with the threshold voltage and saturation voltage decreased by 15% and 16% under the same condition, which is attributed to the uniform dispersion of pinecone-like Fe₂O₃ in nematic LC 5CB and the adsorption of impurity ions by the rough surface of pinecone-like Fe₂O₃ abating the shielding effect.

Key words: liquid crystal display, semiconductor nanomaterials, pinecone-like Fe₂O₃, nematic liquid crystal(NLC), electro-optical properties

王猛,王岩,韦德泉,梁兰菊,王岳平,张彬. 松果状纳米氧化铁对液晶电光性能的影响[J]. 应用化学, 2019, 36(5): 578-584.

WANG Meng,WANG Yan,WEI Dequan,LIANG Lanju,WANG Yueping,ZHANG Bin. Influence of Pinecone-Like Ferric Oxide on the Electro-Optical Properties of Nematic Liquid Crystals[J]. Chinese Journal of Applied Chemistry, 2019, 36(5): 578-584.

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