Hwang, Hyeon Seong Lee, Jongsu Kang, Byungsoo Kim, Minhye Kim, Doyo Kim, Se-Um 2025-08-20T07:09:24Z 2025-08-20T07:09:24Z 2025-08-20 2025-07 https://pubs.kist.re.kr/handle/201004/153003 Broadband near-infrared (NIR) reflective films are widely used in architecture and the automotive and aerospace industries for energy saving and thermal regulation. For large-area and flexible applications, it is essential to develop cost-effective, solution-processable, and long-term-stable NIR-reflective films. Here, we present a polymer-stabilized chiral liquid crystal (CLC) film that achieves broadband NIR reflection by stacking opposite-handed CLC layers with pitch gradients. We experimentally established optimal formulations of materials for both right-handed and left-handed CLCs. The resulting film exhibits high-degree broadband reflection (similar to 95%) in the 1000-1800 nm wavelength range, while maintaining visible transmittance (similar to 80%) in the 450-850 nm range. The concept proposed here will be widely applicable for scalable and practical NIR-filtering applications in smart glasses, sensors, and optoelectronic devices. English Multidisciplinary Digital Publishing Institute (MDPI) Broadband Near-Infrared Reflective Film from Stacked Opposite-Handed Chiral Liquid Crystals with Pitch Gradients Article 10.3390/cryst15070597 1 Crystals, v.15, no.7 Crystals 15 7 Y scie scopus 001540920600001 2-s2.0-105011645288 Crystallography Materials Science, Multidisciplinary Crystallography Materials Science Article DISTRIBUTED-BRAGG-REFLECTOR chiral liquid crystal pitch gradient polymer-stabilized liquid crystal ultraviolet absorption dye near-infrared reflection