花状掺杂W-VO$lt;sub$gt;2$lt;/sub$gt;/ZnO热致变色纳米复合薄膜研究

为解决掺杂引起的二氧化钒薄膜的红外调制幅度下降以及二氧化钒复合薄膜相变温度需要进一步降低等问题, 采用纳米结构、掺杂改性和复合结构等多种机理协同作用的方案, 利用共溅射氧化法, 先在石英玻璃上制备高(002)取向的ZnO薄膜, 再在ZnO层上室温共溅射沉积钒钨金属薄膜, 最后经热氧化处理获得双层钨掺杂W-VO₂/ZnO纳米复合薄膜. 利用X射线衍射、X射线光电子能谱、扫描电镜和变温光谱分析等对薄膜的结构、组分、形貌和光学特性进行了分析. 结果显示, W-VO₂/ZnO 纳米复合薄膜呈花状结构, 取向性提高, 在保持掺杂薄膜相变温度(约39 ℃)和热滞回线宽度(约6 ℃)较低的情况下, 其相变前后的红外透过率差量增加近2倍, 热致变色性能得到协同增强. 关键词： 2')" href="#">VO₂ ZnO W掺杂 热致变色

Thermochromic properties of W-doped VO2/ZnO nanocomposite films with flower structures

Based on the nanocomposite structure and doping modification, we have studied the preparation technology of high performance nanocomposite thin film and its characterization methods. The W-doped VO₂/ZnO nanocomposite thin films are prepared successfully on SiO₂ substrates by the three-step method. The structure and morphology of the W-doped VO₂/ZnO/SiO₂ films are analyzed by X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscope. Results show that the films are mainly composed of VO₂ and high valence cation W⁶⁺ replacing the V ion in the W-doped VO₂/ZnO/SiO₂ films. It is found that the flake nanocrystallines resemble a flower in shape, and its size and orientational growth are reduced. The thermochromic properties of W-doped VO₂/ZnO films are measured and compared with the single-layer W-doped VO₂ films on SiO₂ substrates with the same thickness. The variation of infrared transmittance of the W-doped VO₂/ZnO/SiO₂ nanocomposite film is increased nearly two times, the phase transition temperature reduced approximately to 39 °C, and the width of the thermal hysteresis loop is about 6 °C. The W-doped VO₂/ZnO/SiO₂ nanocomposite film has a high infrared modulation ability, a lower phase transition temperature, and a narrower thermal hysteresis loop. Thus the potential application of this nanocomposite film is significantly improved.
Keywords： 2')" href="#">VO₂ ZnO W-doped thermochromism