木材基银钛复合薄膜的制备及其可见光降解甲醛

 以水热合成法和银镜反应，以木材为基质，制备了微纳米结构的二氧化钛和纳米银复合薄膜。采用场发射电子扫描电镜（SEM）、X射线衍射仪（XRD）、透射电镜（TEM）、光电子能谱仪（XPS）和紫外光分光光度计（UV-vis），对制备的银钛复合薄膜负载的木材基材料微观形貌、晶型结构、化学状态及光学性能进行表征，通过实验证明该银钛复合薄膜负载的木材在可见光照射下具有降解甲醛的作用。结果表明，在可见光照射下，相比单纯的二氧化钛薄膜负载的木材，银钛复合薄膜负载的木材降解甲醛性能显著提升。在此异质结构的体系中，由于银的费米能级低于二氧化钛的导带能级，因此银纳米粒子可作为电子捕获中心以控制电子和空穴的分离，从而提高材料的光催化性能。

Preparation of Ag/Ti composite film based on wood substrate and the formaldehyde degradation under visible light irradiation

The micro-nano Ag-TiO₂ composite film on the surface of wood substrate is fabricated using the hydrothermal synthesis and silver mirror method. The morphological feature, the crystal form, the chemical state and the optical properties of the as-prepared TiO 2/Agcoated wood are analyzed using the field emission scanning electron microscopy(FESEM), the X-ray diffraction(XRD), the transmission electron microscopy(TEM), the X-ray photoelectron spectroscopy(XPS) and the UV-vis diffusion reflectance spectroscopy(UV-vis). Meanwhile, it is shown that the TiO₂/Ag-coated wood has the property of formaldehyde degradation under the visible light irradiation. In this heterostructured system, due to the fact that the Fermi level of Ag is lower than the conduction band of TiO₂, the Ag nanoparticles can act as the electron scavenging centers to cause the electron and hole separation, leading to the enhanced photo-catalytic activity of TiO 2. In this paper, a new material for formaldehyde degradation is prepared, and the functional wood-based materials have great potential applications in new-style functional materials.