Efficient Heat Shielding and Ultraviolet Isolating Transparent Wood via In Situ Generation of TiO2 Nanoparticles

As a new energy-saving building material, optically transparent wood (TW) shows great application potential due to its performance in high light transmittance, high haze, and excellent thermal insulation properties. Herein, a dual functional TW with strong ultraviolet (UV) protection and good thermal insulation properties has been prepared by in situ generation of uniformly dispersed TiO2 nanoparticles in epoxy resin. As is known, TiO2 is generally a wide-band-gap semiconductor with high sensitivity to UV light. As expected, the UV transmittance of the obtained TW-3 containing TiO2 is only 20% for UV light of 250-400 nm. More importantly, this dual-functional TW-3 possesses a lower thermal conductivity (0.3228 W/mK). These performances are significantly better than that of traditional glass. In addition, the as-prepared bifunctional TW-3 also exhibits high light transmittance (90%) and haze (90%), which results in a higher transmission efficiency and more vital privacy than conventional glass. This work provides a new method to design a high-performance wood-based material for green and energy saving thermal insulation windows.