Concepedia

Transparent nanopaper with tailored optical properties

Hongli Zhu, Sepideh Parvinian, Colin Preston, Oeyvind Vaaland, Zhichao Ruan, Liangbing Hu

Nanoscale · 2013 · 251 citations · 22 references

TL;DR

Nanopaper is a flexible, transparent, renewable substrate that can replace plastic in green electronics, with its transparency arising from fibers much smaller than the wavelength of light, which reduces scattering, and its hierarchical structure of many small fibers. This study demonstrates a nanopaper design with varying fiber diameters, showing that light transmittance and scattering depend on both diameter and packing density. The authors explain these optical properties using Chandrasekhar’s radiative‑transfer theory and multiple‑scattering simulations. The resulting controllable optical properties of highly transparent nanopaper open unprecedented opportunities for next‑generation optoelectronics.

Abstract

Nanopaper is a flexible, transparent, and renewable substrate that is emerging as a replacement for plastic in printed "green" electronics. The underlying science of transparency of nanopaper is that the diameter of these fibers is much smaller than the light wavelength, which significantly decreases the light scattering as compared to regular fibers. Cellulose fibers have a hierarchical structure, which consists of numerous smaller fibers. In this manuscript, we demonstrate a nanopaper design with different fiber diameters, and conclude that the light transmittance and scattering depend on the fiber diameter and packing density. The optical properties of the nanopaper and their dependence on the cellulose fiber diameter are thoroughly explained through Chandrasekhar's radiative-transfer theory and multiple scattering method simulations. The controllable optical properties of highly transparent nanopaper present an unprecedented opportunity for growth of next-generation optoelectronics.