Study On Preparation Of Ions Doped Nanotitania And Photocatalytic Dedradation Of Phenol Under UV Irradiation

The nanoparticle titanium dioxide was prepared with tetrabutyl titanate which were former material in the sol-gel process. The experiments showed that the most suitable sol-gel process conditions should control as follows: the tetrabutyl titanate dosage was 15 mL; the anhydrous ethanol dosage was 150 mL; the chlorhydric acid dosage was 3 mL; the drying temperature was 80 oC and the calcined condition that was the calcined temperature was about 520 oC and the calcined time was about 2 h. According to the XRD analysis, the nanoparticle titanium dioxide was anatase in process, the particles diameter was 19.94 nm.We investigated TiO₂ mono-doped and co-doped with Fe, Mn the other 7 metal ions as dopant, and with non-metal or non-metal and metal on TiO₂ photocatalysis system in this paper. In addition, the samples had been characterized by XRD and BET analysis.The degradation of phenol under ultraviolet irradiation with the doped or pure TiO₂ as catalyst was investigated. The results showed: (1) The mono-doped TiO₂ had higher photocatalytic activity than the pure TiO₂, especially, the photocatalytic activity of Mn doped TiO₂ was the highest in all the mono-doped TiO₂ prepared in this study. The effect of the 9 metal ions on photocatalytic activity of mono-doped TiO₂ was in an order of Mn>Ce>Co>Zn>Cr>Ni>Cu> Fe>Mo. (2) For TiO₂ co-doped with two different metal ions, a right proportion between two metal ions could bring cooperation effect. Fe(1.0%)/Ce(2.0%) -TiO₂ and Fe(0.25%)/Mn(2.0%)-TiO₂ and Ce(0.5%)/Mn(2.0%)-TiO₂ co-doped had remarkable cooperation effect. Compared with the pure TiO₂, Mo(0.25%) /Mn(2.0%)-TiO₂ and Cu(1.0%)/Ce(2.0%)-TiO₂ and Ni(1.0%)/Zn(1.5%)-TiO₂ could increase the photocatalytic activities, however, Mo(2.0%)/Fe(1.0%)-TiO₂ and Co(2.0%)/Cu(0.5%)-TiO₂ and Zn(2.0%)/Cu(0.5%)-TiO₂ could decrease. (3) The photocatalytic activities of TiO₂ was increased by using non-metal(N,B) doped TiO₂ as photocatalysis, and using non-metal and metal co-doped TiO₂ could obtain the synergistic effect in proper doping proportion.Phenol solution was used as a simulate pollution and discussed degradating phenol under different conditions: the TiO₂ photocatalyst dosage and initial pH. We investigated the mechanism of degradating phenol. Meanwhile, the additional transition metal ions in the undoped TiO₂ photocatalytic system could impact photocatalytic efficiency of TiO₂ photocatalyst.