Tran Van Tan, Lee Dong Kyu, Kim Jeonghyo, Jeong Ki-Jae, Kim Chang-Seok, Lee Jaebeom
Department of Chemistry, Chungnam National University, Daejeon 34134, Republic of Korea.
Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 46241, Republic of Korea.
ACS Appl Mater Interfaces. 2020 Apr 8;12(14):16584-16591. doi: 10.1021/acsami.9b22684. Epub 2020 Mar 26.
One-dimensional nanostructures with controllable aspect ratios are essential for a wide range of applications. An approach for magnetic superparticle (SP) assembly over large areas (55 mm × 25 mm) is introduced via co-assistance of electrostatic and magnetic fields, so-called magnetic layer-by-layer assembly, on an arbitrary hydrophilic substrate within minutes. The SP structures [diameter () = 120-350 nm] of FeO or Ag@FeO composites composed of hundreds of magnetite nanocrystals ( = 10-20 nm) are used as colloidal monomers to fabricate arrays of high aspect ratio (up to 10) linear nanochains, . colloidal polymers, where thermal disturbances were minimized. The arrays of colloidal polymers exhibit strong optical polarization effects owing to their geometrical anisotropy, which can be used as a simple optical filter. Furthermore, by using the binary colloidal mixture of different magnetic colloids, including different sized FeO and magnetoplasmonic Ag@FeO, low aspect ratio (2-15) colloidal chains, . magnetic/plasmonic oligomers, with tunable lengths were fabricated, affording a facile but an effective approach to modulate the optical properties of the chains. The scalable fabrication of well-aligned, linear colloidal polymers and oligomers opens up appealing opportunities for the development of sensors, subwavelength waveguides, optical tweezers, and enhanced solar harvesting devices.
具有可控纵横比的一维纳米结构对于广泛的应用至关重要。通过静电场和磁场的共同辅助，即在几分钟内在任意亲水基底上引入一种在大面积（55毫米×25毫米）上进行磁性超粒子（SP）组装的方法，即所谓的磁性逐层组装。由数百个磁铁矿纳米晶体（ = 10 - 20纳米）组成的FeO或Ag@FeO复合材料的SP结构[直径（） = 120 - 350纳米]用作胶体单体，以制造高纵横比（高达10）的线性纳米链阵列，即胶体聚合物，其中热干扰被最小化。胶体聚合物阵列由于其几何各向异性而表现出强烈的光学偏振效应，可作为一种简单的光学滤波器。此外，通过使用不同磁性胶体的二元胶体混合物，包括不同尺寸的FeO和磁等离子体Ag@FeO，制备了具有可调长度的低纵横比（2 - 15）胶体链，即磁性/等离子体低聚物，为调节链的光学性质提供了一种简便而有效的方法。排列良好的线性胶体聚合物和低聚物的可扩展制造为传感器、亚波长波导、光镊和增强型太阳能收集装置的开发开辟了有吸引力的机会。
