Anisotropic Optical and Frictional Properties of Langmuir-Blodgett Film Consisting of Uniaxially-Aligned Rod-Shaped Cellulose Nanocrystals
Anisotropic Optical and Frictional Properties of Langmuir-Blodgett Film Consisting of Uniaxially-Aligned Rod-Shaped Cellulose Nanocrystals
复制标题
DOI：
10.1002/admi.201902169
复制
发表时间：
2020-05-01
影响因子：
5.4
通讯作者：
Kim, Seong H.
中科院分区：
文献类型：
--
作者：
Chae, Inseok;Ngo, Dien;Kim, Seong H.
LB膜沉积提供了在单层水平上控制各向异性纳米颗粒的堆积密度和取向的机会，从而允许准确表征其各向异性材料特性。棒状纤维素纳米晶体（CNC）在宏观上大面积上的单轴沉积通过将LB槽上的CNC的长轴与在从LB槽垂直拉动衬底期间弯月面内的最大拖曳力的方向对准来实现。在单轴取向LB膜上，分别用Mueller矩阵谱和频产生谱得到了CNCs的各向异性线性和非线性光学性质，并用含时密度泛函理论计算进行了解释.此外，LB膜的摩擦各向异性测量使用原子力显微镜和理论解释。本研究结果对于制备均匀排列的各向异性纳米粒子薄膜以及利用其各向异性材料特性具有重要的参考价值。
Langmuir-Blodgett (LB) film deposition gives an opportunity to control the packing density and orientation of anisotropic nanoparticles at a monolayer level, allowing accurate characterization of their anisotropic material properties. The uniaxial deposition of rod-shaped cellulose nanocrystals (CNCs) over a macroscopically large area is achieved by aligning the long axis of CNCs on the LB trough with the direction of the maximum drag force within the meniscus during the vertical pulling of the substrate from the LB trough. On the uniaxially-aligned LB films, anisotropic linear and non-linear optical properties of CNCs are obtained using Mueller matrix spectroscopy and sum frequency generation spectroscopy, respectively, and explained with time-dependent density functional theory calculations. Also, the frictional anisotropy of the LB film is measured using atomic force microscopy and explained theoretically. The findings of this study will be valuable for preparation of anisotropic nanoparticle thin films with uniform arrangements and utilization of their anisotropic material properties.