State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai 200050, China.
ACS Appl Mater Interfaces. 2014 Jan 8;6(1):9-13. doi: 10.1021/am405006g. Epub 2013 Dec 23.
Thermochromic VO2 nanoparticles have been dispersed into polyvinyl pyrrolidone (PVP) fibers by electrospinning of a VO2-PVP blend solution. The structure and optical properties of the obtained composite fiber mat were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet-visible (UV-Vis) spectrophotometry, and Fourier transform infrared (FT-IR) spectroscopy. The fiber mat revealed two diffuse reflectance states in infrared spectral region at temperatures under and above the phase transition temperature of VO2 and its IR reflectance is smaller in high temperature. The difference of diffuse reflectance between the two states (ΔRdif) was obvious to be more than 25% in the wavelengths from 1.5 μm to 6 μm. The diffuse reflectance of the fiber mat could be controlled by adjusting the diameter of the fiber or the content of VO2 in the fibers and this particular optical property was explained by a multiple scattering-absorbing process.
通过将 VO2-PVP 共混溶液进行静电纺丝，将热致变色 VO2 纳米粒子分散到聚乙烯吡咯烷酮（PVP）纤维中。通过 X 射线衍射（XRD）、扫描电子显微镜（SEM）、紫外可见分光光度计（UV-Vis）和傅里叶变换红外（FT-IR）光谱对所得复合纤维垫的结构和光学性质进行了研究。纤维垫在低于和高于 VO2 相变温度的红外光谱区域显示出两种漫反射状态，其在高温下的红外反射率较小。两种状态之间的漫反射差异（ΔRdif）在 1.5μm 至 6μm 的波长范围内明显超过 25%。通过调整纤维的直径或纤维中 VO2 的含量，可以控制纤维垫的漫反射，这种特殊的光学性质可以通过多次散射吸收过程来解释。
