Characterization of SrWO4–PVA and SrWO4 spiders’ webs synthesized by electrospinning

Mixtures of strontium acetate, ammonium metatungstate hydrate, and different contents of poly (vinyl alcohol) (PVA, 125,000 MW) were electrospun by a +15 kV direct voltage to synthesize SrWO4–PVA spiders’ webs. The spider's web, synthesized from the solution containing 1.3 g PVA, was further calcined in air at 300–600 °C for 3 h. The SrWO4–PVA spider's web was analyzed by thermogravimetric analyzer (TGA) to specify the evaporation and decomposition of PVA and volatile components. In addition, the SrWO4–PVA and SrWO4 spiders’ webs were characterized by X-ray diffractometer (XRD), selected area electron diffraction (SAED), scanning and transmission electron microscopes (SEM, TEM), and ultraviolet (UV)–visible and photoluminescence (PL) spectrometers, including the vibration modes by Fourier transform infrared (FTIR) and Raman spectrometers. A possible formation mechanism of SrWO4–PVA and SrWO4 spiders’ webs was also proposed according to the experimental results.