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Optofluidic Assembly of Colloidal Photonic Crystals with Controlled Sizes, Shapes, and Structures

Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 305-701 (Korea)
Advanced Materials (Impact Factor: 15.41). 05/2008; 20(9):1649 - 1655. DOI: 10.1002/adma.200703022

ABSTRACT The fabrication of various photonic structures with negligible cracking through evaporation-free colloidal self-assembly using silica particles dispersed in ethoxylated trimethylolpropane triacrylate (ETPTA) resin was investigated. The spherical photonic crystal balls, all of the same size, was prepared by using simple and high-throughput microfluidic devices. The emulsion drops were elongated initially but relaxed to a spherical shape if the particle concentration was not too high to immobilize the interface. The microfluidic device produced highly monodisperse emulsion drops, of which the size was proportional to the diameter of the inner capillary. It was observed that the proposed fabrication scheme was effective for creating non-close-packed colloidal crystals with well-controlled shapes and lattice constants.

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Available from: Shin-Hyun Kim, Jul 28, 2015
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    • "Scale bars b = 10 lm and c = 100 lm. This image is reproduced with permission from Kim et al. (2008). Ó 2008 Wiley–VCH Verlag GmbH & Co. KGaA Microfluid Nanofluid energy requirements (Tao et al. 2008). "
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