Zhang Liangmiao, Wang An, Zhu Tianli, Chen Zhang, Wu Yupeng, Gao Yanfeng
School of Materials Science and Engineering, Shanghai University, 99 Shangda Rd., Shanghai 200444, China.
Department of Architecture and Built Environment, Faculty of Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
ACS Appl Mater Interfaces. 2020 Aug 5;12(31):34777-34783. doi: 10.1021/acsami.0c06494. Epub 2020 Jul 21.
Two types of transparent wood composites with anisotropic structure for energy-saving windows were successfully fabricated by infiltration of epoxy resin dispersion containing tungsten-doped vanadium dioxide nanoparticles (W-doped VO NPs) into the delignified wood template and subsequent polymerization. The well integration of the epoxy resin, W-doped VO NPs, and the pore-structured wood endowed the anisotropic composites with high visible transmittance (68.2% for the composite prepared from longitudinally cut trees (L-composite), 73.3% for the composite prepared from radically cut trees (R-composite)), obviously different mechanical performance (fracture stress of 74.57 MPa (L-composite) and 56.14 MPa (R-composite) and modulus of 1.47 GPa (L-composite) and 1.23 GPa (R-composite)), and low thermal conductivity (0.20 W·m K (L-composite) and 0.32 W·m K (R-composite)). Moreover, these two kinds of W/VO transparent wood composites both show an outstanding thermoregulation ability when they are used as windows. A significant amount of heat (from a simulated light source) was reflected by VO NPs, and as a result, the indoor temperature of a demo system had a significant slower temperature increase rate when compared with that for a similar system with a common glass panel applied. Novel transparent wood composites combining a low thermal conductivity wood template and thermochromic VO NPs provide a potential solution for replacement of heavy, high thermal conductivity, and infrared transparent glass but still meet indoor occupancy view perception.
通过将含有钨掺杂二氧化钒纳米颗粒（W掺杂VO NPs）的环氧树脂分散体渗入脱木质素木材模板并随后聚合，成功制备了两种用于节能窗户的具有各向异性结构的透明木材复合材料。环氧树脂、W掺杂VO NPs和孔隙结构木材的良好结合赋予了各向异性复合材料高可见光透过率（纵向切割树木制备的复合材料（L复合材料）为68.2%，径向切割树木制备的复合材料（R复合材料）为73.3%）、明显不同的力学性能（L复合材料的断裂应力为74.57 MPa，R复合材料为56.14 MPa；L复合材料的模量为1.47 GPa，R复合材料为1.23 GPa）以及低导热率（L复合材料为0.20 W·m K，R复合材料为0.32 W·m K）。此外，这两种W/VO透明木材复合材料用作窗户时均表现出出色的温度调节能力。大量热量（来自模拟光源）被VO NPs反射，因此，与应用普通玻璃板的类似系统相比，演示系统的室内温度上升速率明显更慢。将低导热率木材模板和热致变色VO NPs相结合的新型透明木材复合材料为替代厚重、高导热率且红外透明的玻璃提供了一种潜在解决方案，同时仍能满足室内居住者的视觉感受。
