以鑭系金屬Nd、Sm、La改質二氧化鈦光催化降解染料Acid Red 27之研究

Abstract

Lanthanide ions （Nd3＋﹐Sm3＋ and La3＋） doped TiO2 nanoparticles were successfully synthesized by sol-gel method. Their photocatalytic activities were evaluated that using Acid Red 27(AR27) as a decomposition objective. The structural features of TiO2 and lanthanide ions/TiO2 were investigated by Field emission scanning electron microscope （FE-SEM）, Electron spectroscopy for chemical analysis system （ESCA）, X-ray diffractometer（XRD） and Partical size and zeta potential analyzer（pHzpc）. The adsorption abilities and photocatalytic activity of Lanthanide ions-TiO2 were evaluated by AR 27 degradation under UV light and visible light illumination. The XRD pattern of TiO2 presents is only anatase phases, but Lanthanide-TiO2 presents are both anatase and rutile phases. The contents of the rutile phase increased with increase of the molar ratio of Lanthanide-TiO2. The SEM image of the Lanthanide-TiO2 showed particles of regular shape with smaller size ＜15 nm compare to the TiO2, which presented uniform particles of spherical structure and larger size about 30 nm. The valence number of Nd-TiO2 photocatalyst were not altered and Neodymium on TiO2 structure was in the status of Nd0 and Nd3＋；Samarium on TiO2 structure was in the status of Sm3＋；Lanthanum on TiO2 structure was in the status of La3＋. The pHzpc of Lanthanide-TiO2 phtotcatalyst were hight than pure TiO2. The result presented that the Lanthanide-TiO2 is powerful to treat dye ,color and TOC. In the FTIR spectrum, the peaks of N=N double bond was eliminated after the Lanthanide-TiO2 reaction. Compare with TiO2, the Lanthanide-TiO2 have better response of UV light and visible light. In UV light and visible light system, at pH 4 and 7 have better discoloration and mineralization.