Optical Properties And Biomimetic Applications Of Natural Photonic Nanostructures

Fast-developing technology and industry place urgent calls on novel high-efficient and environment-friendly optical nano-materials, which contribute to better life and sustainable living. Distinct novel optical properties can be achieved by applying carefully designed nanostructures into appropriate materials due to the nanometer confinement of radiation.Compared with our finite knowledge, nature provides us millions of years of research that can help us. With a goal to achieve high performance nanophotonic design in a biomimetic manner, this study has been carried out with emphasis on three sections.Section?I mainly reports the discovery of three different types of novel nano-scale antireflection architectures in the dorsal scales of the black wings of butterfly Ornithoptera goliath, Troides aeacus and Papilio helenus Linnaeus respectively. The corrugated and porous architectures help reduce additive reflective energy loss from 14% in visible light for a planar scale to merely ~1% or even less, and contribute more than 10% increase in absorption, which can improve the competitiveness of the butterflies for survival.Section II mainly describes an ultrathin but super black a-C film which is inspired by the anti-reflection inverse-V type architecture in black wings of butterfly Onithoptera goliath. This film achieved super blackness of an average of 99% light absorption and less than 1% reflection in the visible light spectrum (380nm-795nm). Compared with the flat plate amorphous carbon film, reflection reduces approximately 12 times. Reflection of the V-type surface a-C also reduces 7 times than that of glassy carbon whose reflection is about 8%.Sectionâ…¢mainly discusses the effects of the natural hierarchical nano-pores on light harvesting efficiency and light emitting efficiency of the leaf-templated Eu3+ doped calcium silicate phosphor. The hierarchical nano-pores are arranged in layers which are characterized by the average pore size. The layered structure acts as a graded refractive index interface which greatly reduced wanted reflective radiation. The nano-pores also create much larger surface area and pore-volume, which also increase the light emitting property of the materials.