Kühnel Miguel R Carro-Temboury Martin, Ahmad Mariam, Andersen Frederik, Bech Ári Brend, Bendixen H Krestian L, Nawrocki Patrick R, Bloch Anders J, Bora Ilkay, Bukhari Tahreem A, Bærentsen Nicolai V, Carstensen Jens, Chima Smeeah, Colberg Helene, Dahm Rasmus T, Daniels Joshua A, Dinckan Nermin, Idrissi Mohamed El, Erlandsen Ricci, Førster Marc, Ghauri Yasmin, Gold Mikkel, Hansen Andreas, Hansen Kenn, Helmsøe-Zinck Mathias, Henriksen Mathias, Hoffmann Sophus V, Hyllested Louise O H, Jensen Casper, Kallenbach Amalie S, Kaur Kirandip, Khan Suheb R, Kjær Emil T S, Kristiansen Bjørn, Langvad Sylvester, Lund Philip M, Munk Chastine F, Møller Theis, Nehme Ola M Z, Nejrup Mathilde Rove, Nexø Louise, Nielsen Simon Skødt Holm, Niemeier Nicolai, Nikolajsen Lasse V, Nøhr Peter C T, Orlowski Dominik B, Overgaard Marc, Ovesen Jacob Skaarup, Paustian Lucas, Pedersen Adam S, Petersen Mathias K, Poulsen Camilla M, Praeger-Jahnsen Louis, Qureshi L Sonia, Ree Nicolai, Schiermacher Louise S, Simris Martin B, Smith Gorm, Smith Heidi N, Sonne Alexander K, Zenulovic Marko R, Sørensen Alma Winther, Sørensen Karina, Vogt Emil, Væring Andreas, Westermann Jonas, Özcan Sevin B, Sørensen Thomas Just
Nano-Science Center & Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 København Ø, Denmark.
Nanomaterials (Basel). 2018 Feb 15;8(2):109. doi: 10.3390/nano8020109.
Three series of ionic self-assembled materials based on anionic azo-dyes and cationic benzalkonium surfactants were synthesized and thin films were prepared by spin-casting. These thin films appear isotropic when investigated with polarized optical microscopy, although they are highly anisotropic. Here, three series of homologous materials were studied to rationalize this observation. Investigating thin films of ordered molecular materials relies to a large extent on advanced experimental methods and large research infrastructure. A statement that in particular is true for thin films with nanoscopic order, where X-ray reflectometry, X-ray and neutron scattering, electron microscopy and atom force microscopy (AFM) has to be used to elucidate film morphology and the underlying molecular structure. Here, the thin films were investigated using AFM, optical microscopy and polarized absorption spectroscopy. It was shown that by using numerical method for treating the polarized absorption spectroscopy data, the molecular structure can be elucidated. Further, it was shown that polarized optical spectroscopy is a general tool that allows determination of the molecular order in thin films. Finally, it was found that full control of thermal history and rigorous control of the ionic self-assembly conditions are required to reproducibly make these materials of high nanoscopic order. Similarly, the conditions for spin-casting are shown to be determining for the overall thin film morphology, while molecular order is maintained.
合成了基于阴离子偶氮染料和阳离子苯扎氯铵表面活性剂的三系列离子自组装材料，并通过旋涂法制备了薄膜。尽管这些薄膜具有高度的各向异性，但用偏光显微镜研究时却呈现出各向同性。在此，研究了三系列同源材料以合理解释这一现象。研究有序分子材料的薄膜在很大程度上依赖于先进的实验方法和大型研究基础设施。对于具有纳米级有序性的薄膜来说尤其如此，在这种情况下，必须使用X射线反射测量法、X射线和中子散射、电子显微镜以及原子力显微镜（AFM）来阐明薄膜形态和潜在的分子结构。在此，使用AFM、光学显微镜和偏振吸收光谱对薄膜进行了研究。结果表明，通过使用数值方法处理偏振吸收光谱数据，可以阐明分子结构。此外，结果表明偏振光学光谱是一种通用工具，可用于确定薄膜中的分子有序性。最后，发现要可重复地制备出具有高纳米级有序性的这些材料，需要完全控制热历史并严格控制离子自组装条件。同样，旋涂条件被证明对整体薄膜形态起决定性作用，同时分子有序性得以保持。
