镧掺杂的二氧化钛纳米粒子的制备表征及光催化性能研究

【作者】 孙志华；

【导师】 袁福龙； 井立强；

【作者基本信息】 黑龙江大学 ， 无机化学， 2005， 硕士

【摘要】 为了进一步改善TiO₂光催化剂的活性,本文采用了La掺杂及La和Cu共掺杂的改性方法。利用溶胶-水热法制备La掺杂及La和Cu的共掺杂的TiO₂纳米催化剂,重点考察了掺杂量和焙烧温度对光催化活性的影响。通过XRD,PL和SPS等方法分析了改性机制。结果表明:La的掺杂有效地抑制了TiO₂的相转变。适当量的La掺杂和焙烧温度能够提高样品的光催化活性,这与表征结果是一致的,即样品SPS信号越强、PL光谱信号越强、光催化活性越高。说明了样品光催化活性主要受TiO₂晶相组成和结晶度的影响。通过对溶胶-水热法和溶胶-凝胶法的比较研究,发现溶胶-水热法的制备样品的活性要高于溶胶-凝胶法,分析认为主要与前者的分散性较好有关。 在La和Cu共掺杂改性过程中,两种改性剂并不存在显著的协同效应,在实验范围内活性提高并不显著。 证实可通过SPS和PL的初步测试来评价TiO₂光催化剂的活性。更多还原

【Abstract】 In this thesis, we adopted La-doped and La/Cu together doped modification method to improve the photocatalytic activity of titanium dioxide （TiO₂） photocatalysts. The La and La/Cu together doped TiO₂ nanocatalsts were prepared by sol-hydrothermal method, the influence of quantities of doped and calcinating temperature on the activity of catalysis was investigated principal. And the XRD, PL, and SPS methods characterized the mechanisms of modification. The results indicated that the doping of La inhibited the phase transformation of TiO₂. And the photocatalytic activity of samples was improved through suitable doping quantities and calcinating temperature, which was in agreement with the results of characterization, i.e. the more intensity of SPS signal of samples, the more intensity of spectrum, the more photocatalytic activity. It indicated that compose and crystallinity of the TiO₂ crystalline phase had a predominant effect on the photocatalytic activity of samples. It was shown that the photocatalytic activity of TiO₂ catalysts that were prepared by sol-hydrothermal method was better than that prepared by sol-gel method from the comparison investigations of sol-hydrothermal and sol-gel methods, which result in the better dispersiveness of the former.In the La/Cu complex doped and modification processes, there wasn’t remarkable cooperation effect between the two modifying agents, and the photocatalytic activity was improved unremarkable of our experiments.It was confirmed that the activity of TiO2 photocatalysts could be estimated by the preliminary testing of SPS and FS methods.更多还原