• Mioduska, Joanna

Abstract

<jats:p>Series of WO<jats:sub>3</jats:sub>/TiO<jats:sub>2</jats:sub>nanocomposites were obtained by hydrothermal method followed by calcination in the temperature range from 400°C to 900°C. The characteristics of photocatalysts by X-ray diffractometry (XRD), scanning electron microscope (SEM), and diffuse reflectance spectroscopy (DRS) showed that increasing the calcination temperature from 400 to 900°C resulted in change of photocatalytic activity under UV-Vis light. Moreover, the amount of WO<jats:sub>3</jats:sub>crystalline phase and amorphous phase in WO<jats:sub>3</jats:sub>/TiO<jats:sub>2</jats:sub>aggregates, as revealed by XRD analysis, was dependent on the calcination temperature. The WO<jats:sub>3</jats:sub>/TiO<jats:sub>2</jats:sub>samples with 8 mol% load of WO<jats:sub>3</jats:sub>in respect to TiO<jats:sub>2</jats:sub>calcinated at 500 and 800°C possess the highest photocatalytic activity in reaction of phenol degradation, which is about 1.2 and 1.5 times that with calcination at 400°C. The increase in calcination temperature above 400°C resulted in increase of WO<jats:sub>3</jats:sub>crystallinity and reduction of the amount of amorphous phase in the nanocomposite structure. Moreover, the annealing of nanocomposites above 700°C decreases the value of optical band gap energies of obtained WO<jats:sub>3</jats:sub>/TiO<jats:sub>2</jats:sub>nanomaterials.</jats:p>

Topics

• nanocomposite
• impedance spectroscopy
• amorphous
• scanning electron microscopy
• x-ray diffraction
• crystalline phase
• annealing
• crystallinity