Study On The Synthesis Of Co-doped Titanium Dioxide And Its Photocatalytic Activity

The nanocrystalline titania with single metal ion and metal ions co-doped titania was prepared by sol-gel technique. Metal, cobalt, lanthanum, cerium, zinc and chromium doped titania was prepared by sol-gel technique. The photocatalytic activity was evaluated by the photocatalytic decomposition of methlyene Blue and the influence of the dopants and their concentration to the effeciency of photocatalic activity were discussed. It was found that co-doping nano-TiO₂ has better performance,their optimism concentration are 0.05% Fe/ 0.01% Zn.From the results of experiments, we draw the conclusions that the optimal reaction temperature is 30℃, the water dosage is 50ml, the pH value is 1.0, the optimal calcined temperature is 500℃ and the best iron content is 0.05%.Thermogravimeteric, X-ray diffraction, scanning electron microscopy, laser diffraction particle size analyzer and UV-Vis spectrophotometer technology were used to characterize the product. The result showed that the samples were rutile and well proportioned. Scanning electron microscopy shows their particle size were 50-60 nm. Moreover, the metal ion co-doped decreases the grain growth rate. Finally, the absorption edge of the iron-doped titanic has a red shift and the sample also has a stronger absorption than the pure titanic in the visible region. Since the iron-doped titanic can absorb light in a wider range of wavelength and utilize more light energy than pure titanic. It follows that a higher photocatalytic activity should be expected in metal ion-doped titanic. The same result is further confirmed by the result of photocatalytic activity methlyene Blue. XPS shows titania lattice is distorted after cobalt ion doped nano-titania and the binding energy of Ti2p was reduced. It follows that a...