Nanostructured hafnium-doped strontium oxide film for homeotropic/homogeneous convertible liquid crystal alignment depending on the curing temperature  

作　　者：Dong Hyun Kim Dong Wook Lee Jin Young Oh Jonghoon Won Hae-Chang Jeong Dae-Shik Seo 

机构地区：[1]IT Nano Electronic Device Laboratory,Department of Electrical and Electronic Engineering,Yonsei University,Seoul,Republic of Korea [2]Department of Smart Manufacturing Engineering,Changwon National University,Changwon,Gyeongnam,Republic of Korea [3]Department of Electrical Electronic and Control Engineering,Changwon National University,Changwon,Gyeongnam,Republic of Korea

出　　处：《International Journal of Smart and Nano Materials》2022年第4期597-611,共15页国际智能和纳米材料杂志（英文）

基　　金：This work was supported by the National Research Foundation of Korea[2020R1G1A1013604].

摘　　要：A hafnium strontium oxide(HfSrO)liquid crystal(LC)alignment film was efficiently created through brush coating,and its ability to change the LC alignment direction was confirmed.A brush was applied to HfSrO sol coated on an indium-tin oxide substrate,after which the coating was solidified at var-ious curing temperatures.It was confirmed that a directional micro/nanostructure was formed above 280°C due to the shear stresses caused by the movement of the brush hairs.Surface chemical changes were analyzed by using X-ray photoelectron spectroscopy and contact angle measurements.As the curing temperature increased,the prevalence of oxygen bonds increased and the contact angle decreased,thereby increasing the surface energy.The anisotropic boundary of the micro-grooves and the van der Waals forces due to an increase in surface energy changed the alignment direction of LC mole-cules from vertical to horizontal,as verified through polarized optical microscopy and pretilt angle measurements.Thus,the efficiency of the brush-coating method,which dramatically simplifies the LC alignment film process,was confirmed.The homeotropic/homogeneous LC alignment property of the HfSrO film produced through brush coating depending on the curing temperature provides an innovative approach for LC alignment.

关 键 词：Brush coating NANOSTRUCTURE solution process liquid crystal alignment 

分 类 号：TB383[一般工业技术—材料科学与工程]