TĂNG CƯỜNG HOẠT TÍNH XÚC TÁC QUANG VÙNG KHẢ KIẾN CỦA TiO2 BẰNG VẬT LIỆU LAI GHÉP TiO2/WO3

Tóm tắt

The nanocomposites photocatalyst of TiO2-WO3 was prepared by sol-gel and combined with
calcination method at 425oC in one hour. The mesoporous WO3-TiO2 photocatalysts with different
loadings of W (12, 14, 15, 17 and 20) wt% were used to remove methylene blue (MB 20%) from
aqueous solution. The prepared photocatalysts were characterized by XRD, FTIR, BET, SEM, UV vis
and EDX analysis. The XRD showed that the samples TiO2-WO3 have signals of phases of TiO2 and
WO3. However, the sample TiO2-WO3 (>20 wt% W) has signals of rutile phases of TiO2. The ultraviolet
visible diffuse reflection spectra (DRS) indicated that the addition of WO3 to TiO2 decrease the band
gap energy. The photocatalytic measurements showed that WO3 combined with TiO2, by which could
hinder the recombination rate of excited electrons/holes and increased the photodegradation of MB to
99% after 150 minutes on the sample 15 wt% TiO2-WO3. The experimental results indicate that under
visible-light irradiation, the optimal dose of the photocatalyst was 1.4 g/l. The TiO2-WO3 photocatalytic
had a high potential for recycling.
Keywords. Photocatalysis, TiO2, WO3 Methylene blue.