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liquid crystal, artificial water channels, AWC, water-induced self-assembly, WISA
Water Nano-Channels in Columnar Liquid Crystals Demonstrated by Hard and Soft X-rays Techniques Highlighted as a Cover Image of JACS
The collaborative research from NSRRC users Chien-Lung Wang and Kuan-Yi Wu, and NSRRC scientists Wei-Tsung Chuang, Chia-Hsin Wang and Zong-Ren Yang, was highlighted as a cover image of JACS. The image illustrated the dual-axis alignment of artificial water channels.
NSRRC users Prof. Chien-Lung Wang (Department of Applied Chemistry, National Yang Ming Chiao Tung University) and Prof. Kuan-Yi Wu (Department of Textile Engineering, Chinese Culture University), as well as NSRRC scientists Dr. Wei-Tsung Chuang, Dr. Chia-Hsin Wang and Dr. Zong-Ren Yang worked in collaboration on the application of artificial water channels on liquid crystal (LC) molecules. Their research results were published in the Journal of the American Chemical Society (JACS) and highlighted as a cover of issue 17.
LC molecules have been a useful material in applications such as organic semiconductors, membranes, and LC displays. The performance of LC materials strongly depends on their self-assembly structures and the degree of orientational order in their morphology. However, current external guiding fields such as electrical, magnetic, and mechanical guiding fields are less effective in aligning amphiphilic LCs. The team developed “water” as an excellent structural stabilizer and orientation-directing agent of an amphiphilic discotic molecule (AD) in the water-induced self-assembly (WISA) process. Thermal analysis and structural characterization results showed that water increased the stability and domain sizes of the hexagonal columnar phase of the AD by co-assembling with the ADs to form bulk artificial water channels (AWCs). Moreover, through control over specific nucleation conditions, dual-axis alignment in both the planar and vertical growth of the AWCs was achieved. With precise control over the hierarchical structures, the bulk AWC array of the AD delivers excellent salt rejection properties and water permeability.
The team used multiple experiment facilities, including TLS 01C2, TLS 23A1, TLS 24A1 and TPS 25A, to investigate the core−shell structure and amphiphilic discotic molecule by various techniques at Taiwan Light Source and Taiwan Photon Source. The team endowed water with an active role in the WISA process, and showed that water can achieve morphological control to an extent exceeding the capability of conventional techniques. This research could launch the further development of functional amphiphilic LCs.