Preparation of Eu~(3+) Doped Titania Nanocrystals and Photocatalytic Degradation Partially Hydrolyzed Polyacrylamide

Nanocrystals with different Eu3+ doping levels were prepared by sol-gel and hydrothermal synthetic methods using titanium tetraisopropoxide (TTIP) as titanium source. The crystallite size, crystal form, surface shape, composition and optical property of the nanocrystals were characterized by X-ray diffraction patterns, UV-Vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and inductively coupled plasma atomic emission spectroscopy. The products exhibited anatase phase structure, with an average size of 9 nm, and Eu3+ entered into the crystal cell of TiO2 (interstitial mode) in the form of Eu2O3. Furthermore, the photocatalytic activity of prepared Eu3+ doped TiO2 was studied by degrading partially hydrolyzed polyacrylamide (HPAM) under UV light irradiation. The results showed that HPAM was completely degraded. Ultimate mineralization ratio reached 67% when Eu3+ loading was 2.4% (w). In addition, intermediate products were detected via liquid chromatography/mass spectrometry, and degradation mechanism was analyzed.