Photochromic Nanofiber Aggregates of PVA/H_3PMo_(12)O_(40) Hybrid

摘要

Poly (vinyl alcohol) (PVA)/H_3PMo_(12)O_(40) ultra-fine fiber aggregates contained differential weight percentage of H_3PMo_(12)O_(40) to PVA (20, 50 and 80 wt.%, respectively) have been successfully prepared by electrospinning technique. By means of IR spectrum, wide-angle X-ray diffraction, and scanning electron microscope (SEM) techniques, the fiber aggregates were characterized. The result from scanning electron microscopy (SEM) showed that the average diameter of the fibers was between 240-900 nm. The photochromic behavior of the fiber aggregates was investigated by means of IR, UV-Vis spectra and electron spin resonance (ESR). The results showed that the Mo atom of H_3PMo_(12)O_(40) was reduced via one-electron step and the PVA was oxidized to unsaturated ketone after the PVA/H_3PMo_(12)O_(40) fiber aggregates was irradiated under UV light. The color of the fiber aggregates changed from white to blue under ultraviolet irradiation and the photochromism of the fiber aggregates was reversible in air condition.