UNAM-National Nanotechnology Research Center, Bilkent University, 06800 Ankara, Turkey.
Nano Lett. 2011 Nov 9;11(11):4661-5. doi: 10.1021/nl2022114. Epub 2011 Oct 21.
We demonstrated two complementary size-dependent structural coloring mechanisms, interference and scattering, in indefinitely long core-shell nanowire arrays. The unusual nanostructures are comprised of an amorphous semiconducting core and a polymer shell layer with disparate refractive indices but with similar thermomechanical properties. Core-shell nanowires are mass produced from a macroscopic semiconductor rod by using a new top-to-bottom fabrication approach based on thermal size reduction. Nanostructures with diameters from 30 to 200 nm result in coloration that spans the whole visible spectrum via resonant Mie scattering. Nanoshell coloration based on thin film interference is proposed as a structural coloration mechanism which becomes dominant for nanowires having 700-1200 nm diameter. Controlled color generation in any part of visible and infrared spectral regions can be achieved by the simple scaling down procedure. Spectral color generation in mass-produced uniform core-shell nanowire arrays paves the way for applications such as spectral authentication at nanoscale, light-scattering ingredients in paints and cosmetics, large-area devices, and infrared shielding.
我们在无限长的核壳纳米线阵列中展示了两种互补的尺寸相关结构色机制，即干涉和散射。这些不寻常的纳米结构由非晶半导体核和具有不同折射率但具有相似热机械性能的聚合物壳层组成。核壳纳米线是通过使用基于热尺寸减小的全新自上而下制造方法，从宏观半导体棒大量生产出来的。直径为 30 至 200nm 的纳米结构通过共振 Mie 散射导致颜色横跨整个可见光谱。基于薄膜干涉的纳米壳颜色被提出作为结构颜色机制，对于直径为 700-1200nm 的纳米线，该机制变得占主导地位。通过简单的缩小程序可以在任何可见光和红外光谱区域实现可控的颜色生成。在大规模生产的均匀核壳纳米线阵列中产生光谱颜色为纳米级光谱认证、涂料和化妆品中的光散射成分、大面积器件和红外屏蔽等应用铺平了道路。
