查看文章

The paper reports on the influence of visible light at different wavelengths (red, λ = 630 nm; green, λ = 570 nm; purple–blue, λ = 430 nm), light irradiance conditions (from 30 to 770 μW/cm²) and operating temperatures (from 25 °C to 100 °C) on the electrical response of WO₃ electrospun nanofibers (NFs) to 100–400 ppb NO₂ gas in dry air. WO₃ NFs were prepared by mixing a W–O sol–gel transparent solution (WCl₆ in ethanol) with a polymeric solution made of polyvinylpyrrolidone (PVP) and dimethylformamide (DMF). Electrospun NFs were annealed between 300 °C and 500 °C and the their microstructures features investigated by SEM and XRD. Room temperature (25 °C) gas responses of the 450 °C annealed NFs have shown that, beside a slight reduction of the relative gas response (RRs), a decrease of the light wavelength (toward the purple–blue) and an increase of its irradiance, greatly improve the base …