2026-11-04 大阪大学

図1:植物由来ナノ材料の特性を生かした多孔質層(「疎」な層)と、同じく植物由来の「密」な層を積層することで、タマムシの翅の構造を再現することに成功。ピーク反射率はタマムシの約3倍。
<関連情報>
- https://www.sanken.osaka-u.ac.jp/achievement/release/20261104.html
- https://advanced.onlinelibrary.wiley.com/doi/10.1002/adma.75473
構造的に変調された全生体高分子多層膜による95%以上の光反射率 Over 95% Optical Reflectance From Structurally Modulated All-Biopolymer Multilayers
Takaaki Kasuga, Ami Mizui, Shun Ishioka, Yintong Huang, Yuto Kaku, Tsuguyuki Saito, Tatsuya Namba, Yohsuke Goi, Hirotaka Koga, Masaya Nogi
Advanced Materials Published: 03 November 2026
DOI:https://doi.org/10.1002/adma.75473
Abstract
Sustainable photonics aims to replace conventional optical materials with environmentally benign alternatives, yet its development is fundamentally constrained by the narrow intrinsic refractive-index variability of biopolymers. Here we show that a dense–porous periodic architecture yields nearly perfect optical reflection using only polysaccharides. By exploiting the difference in skeletal rigidity between amorphous pectin and crystalline cellulose nanofibers (CNFs), we form alternating dense, high-refractive-index pectin layers and porous, low-refractive-index CNF layers through a combination of electrodeposition with solvent exchange. This dense–porous periodic architecture yields reflectivities exceeding 97% in the visible range and 95% in the near-infrared—a range unprecedented for biopolymer-based optical materials. Moreover, the strategy is simple, scalable, and highly versatile, enabling free spectral design across the visible and near-infrared regions, broadband metallic-like reflection, and planar patterning within a single fabrication process. Combined with the low thermal conductivity arising from porous layers and the coexistence of visible transparency and near-infrared reflection, the resulting films show potential as transparent thermal-management materials. This work establishes a new materials design principle for biodegradable, polysaccharide-based photonic systems and advances the field of sustainable photonics.


