二氧化钒纳米点阵的制备及其红外光学特性研究

为了得到相变温度低且变色性能优越的光学材料,使其能够广泛应用于智能窗领域,对周期结构VO2纳米点阵的相变和光学特性展开了研究。用修正的Sellmeier色散模型结合二维点阵周期结构的等效折射率计算了VO2纳米点阵在不同占空比下的反射率和透射率。利用多孔氧化铝模板掩膜溅射法,先在玻璃上制备钒金属纳米点阵,再经热氧化工艺制备出VO2纳米点阵,测试其表面形貌、组分结构、红外反射和透射谱线。结果表明,占空比为0.83的纳米点阵其相变温度有效降低至43℃,在1700 nm处透射率改变量达到29%,表现出良好的变色特性,且透射率整体高于VO2薄膜。说明通过制备较佳占空比的纳米点阵可以有效降低材料的相变温度,提升材料的热致变色性能。

Preparation and Infrared Optical Properties of VO2 Nano Array

The thermo-optic effect and infrared optical properties of VO2 nano array were studied in order to obtain high quality optical material widely used in the field of smart windows. Reflectance and transmittance spectra of VO2 nano array at different duty ratios were calculated with a modificatory Sellmeier dispersion model and equivalent refractive index of two-dimensional periodic structure. The vanadium nano array was deposited on the glass substrate by magnetic reactive sputtering with the mask of porous alumina, and then VO2 nano array was formed by annealing under air condition. Its microstructure and optical properties were characterized by atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and spectrophotometer. The results show that the phase transition temperature of VO2 nano array with duty ratio 0.83 drops to 43 oC and its optical contrast between the metallic and semiconducting states at 1700 nm is 29%, which exhibits a significant thermochromic property. Contrast to VO2 film, the transmittance of VO2 nano array has been noticeably improved. The decrease of phase change temperature and enhancement of optical properties demonstrate that VO2 nano array with decent duty ratio is a competitive candidate material for smart windows