Photon Walk in Transparent Wood: Scattering and Absorption in Hierarchically Structured Materials

The optical response of hierarchical materials is convoluted, which hinders their direct study and property control. Transparent wood (TW) an emerging biocomposite in this category, adds function to the structural properties wood. Nano- microscale inhomogeneities composition, structure at interfaces strongly affect light transmission haze. While interface manipulation can tailor TW properties, realization optically clear requires detailed understanding light-TW interaction mechanisms. Here we show how material scattering absorption coefficients be extracted from a combination experimental spectroscopic measurements photon diffusion model. Contributions different length scales thus deciphered quantified. It shown that forward dominates haze TW, primarily caused by refractive index mismatch between substrate polymer phase. Rayleigh cell wall residual lignin have minor effects on transmittance, but former affects Results provide guidance for design transparent composites towards desired functionality; demonstrate experimentally transmittance controlled over broad range.