TiO2 powder and its photocatalytic activity
Titanium dioxide (titania) nanoparticle were synthesized by coprecipitation process of titanium trichloride (TiCl3) in aqueous medium, with NH4OH as pH regulator. The pH solution was varied during the synthesis process between pH 3-8.4, and all samples were calcined temperature at 400oC for 3 hours. Characteristics and properties of the TiO2 powder were investigated using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM).
XRD results show that the single-phase rutile formed when the pH is less than 5, anatase single phase formed began pH 8, and the pH of the solution between 5-8 formed mixed phase rutile-anatase-brookite, rutile-brookite or
natasebrookite. Methylene Blue (MB) photodegradation test were performed in order to evaluate photocatalytic activity. Nanoparticles TiO2 rutile, anatase phase, and mixed phase rutile-brookite, anatase-brookite used to test the photocatalytic activity by measuring the absorbance spectrum photodegradation using UV-Vis spectrometer. The test results showed that the mixture phase of rutile-brookite provide the greatest photodegradation than other phases.
UV-Vis spectral of sample with variation of illumination time (a) 1 h, (b) 2 h, (c) 3 h, (d) 4 h
(a) degradation, (b) MB % removal