Park, Sihun Lee, Sang Seok Kim, Shin-Hyun 2024-01-19T17:04:12Z 2024-01-19T17:04:12Z 2021-09-05 2020-07 0935-9648 https://pubs.kist.re.kr/handle/201004/118442 Cholesteric liquid crystals (CLCs), also known as chiral nematic LCs, show a photonic stopband, which is promising for various optical applications. In particular, CLCs confined in microcompartments are useful for sensing, lasing, and optical barcoding at the microscale. The integration of distinct CLCs into single microstructures can provide advanced functionality. In this work, CLC multishells with multiple stopbands are created by liquid-liquid phase separation (LLPS) in a simple yet highly controlled manner. A homogeneous ternary mixture of LC, hydrophilic liquid, and co-solvent is microfluidically emulsified to form uniform oil-in-water drops, which undergo LLPS to form onion-like drops composed of alternating CLC-rich and CLC-depleted layers. The multiplicity is controlled from one to five by adjusting the initial composition of the ternary mixture, which dictates the number of consecutive steps of LLPS. Interestingly, the concentration of the chiral dopant becomes reduced from the outermost to the innermost CLC drop due to uneven partitioning during LLPS, which results in multiple stopbands. Therefore, the photonic multishells show multiple structural colors. In addition, dye-doped multishells provide band-edge lasing at two different wavelengths. This new class of photonic multishells will provide new opportunities for advanced optical applications. English WILEY-V C H VERLAG GMBH SELECTIVE REFLECTION COMPLEX EMULSIONS LIGHT PATTERNS DISPLAY SHELLS TWIST Photonic Multishells Composed of Cholesteric Liquid Crystals Designed by Controlled Phase Separation in Emulsion Drops Article 10.1002/adma.202002166 1 ADVANCED MATERIALS, v.32, no.30 ADVANCED MATERIALS 32 30 scie scopus 000539011400001 2-s2.0-85086148614 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article SELECTIVE REFLECTION COMPLEX EMULSIONS LIGHT PATTERNS DISPLAY SHELLS TWIST cholesteric liquid crystals laser resonators liquid-liquid phase separation multiple emulsions photonic shells