【作者】 杨丽萍；

【导师】 双少敏； 赵晓红；

【作者基本信息】 山西大学 ， 分析化学， 2010， 硕士

【摘要】 第一章：简述了半导体光催化机理,光催化剂种类及微波技术在光催化剂制备方面的应用。阐述了钙钛矿型复合氧化物的结构、性质与制备,重点综述了钙钛矿型复合氧化物的催化应用尤其是在光催化方面的研究进展。第二章：以硬脂酸为络合剂,通过溶胶凝胶法制备钙钛矿型La1-xCaxCoO3与La1-xCaxFeO3系列。采用红外光谱、X射线衍射、扫描电镜、透射电镜等现代分析测试手段对粉体的结构、粒径进行分析和表征。比较了微波与常规加热对制备LaCoO3粒子的影响。结果表明制备的La1-xCaxCoO3与La1-xCaxFeO3系列都具有良好的钙钛矿型结构,粒径大小为50～200nm,其中微波法制备的LaCoO3粒子平均粒径达到30nm。并且掺钙量不同,产物的颜色和产量也不同。第三章：以微波硬脂酸溶胶凝胶法合成的钙钛矿型LaCoO3为催化剂,光催化降解酸性品红溶液,研究催化时间、催化剂用量、染料起始浓度与pH值对降解率的影响,并对催化剂的重复利用效果进行了探讨。结果表明,10mg/L酸性品红溶液,用0.2g LaCoO3催化剂降解60min,降解率达到90%；在pH=2的酸性品红溶液中,30min内降解率达到95%以上。说明微波法制备的LaCoO3具有良好的光催化性能。另外,LaCoO3催化剂对酸性品红的降解率高于碱性品红。第四章：以硬脂酸溶胶凝胶法制备的La1-xCaxCoO3为光催化剂,以高压汞灯为光源,采用紫外可见光谱研究了La1-xCaxCoO3系列对活性翠蓝KN-G、活性艳蓝X-BR的光催化降解。考察了催化剂用量、染料起始浓度、钙的掺杂量与光源对活性翠蓝溶液降解率的影响。结果表明掺钙量不同,La1-xCaxCoO3对活性染料的催化降解效果不同。La0.85Ca0.15CoO3光催化降解活性翠蓝效果最佳；La0.9Ca0.1CoO3催化降解活性艳蓝效果最好。汞灯与太阳光对催化剂反应活性的影响有所不同,但对染料总的降解效果相差不大。第五章：采用硬脂酸溶胶凝胶法制备的La1-xCaxFeO3为催化剂,比较其对活性深蓝B-2GLN、活性翠蓝KN-G与活性艳蓝X-BR的光催化降解效果,并对催化时间、催化剂用量和染料初始浓度对降解率的影响进行初步探讨。结果表明掺钙量不同,对三种活性染料的催化降解效果不同。L20.95Ca0.05FeO3对染料的催化降解效果最好。对5～10mg/L活性深蓝与活性艳蓝,5～20mg/L活性翠蓝,La0.85Ca0.15FeO3均有较好的催化效果。更多还原

【Abstract】 Chapter 1:The photocatalysis mechanism of semiconductors, categories of photocatalysts and applications of microwave in photocatalyst preparation were described in brief. By introducing the structure, properties and preparation of the perovskite-type oxides, the applications of the perovskite-type oxides in catalysis were reviewed, and more emphasis was focused on the research developments of the photocatalytic application of the perovskite-type oxides.Chapter 2:Perovskite-type La1-xCaxCoO3 and La1-xCaxFeO3 series were synthesized with sol-gel method by using stearic acid a complexing agent. The structure and particle size of the obtained powder were analyzed and characterized by infrared spectrum(IR), X-ray diffraction(XRD), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The effects of microwave and conventional heating on the preparation of LaCoO3 particles were compared. The results showed that La1-xCaxCoO3 and La1-xCaxFeO3 series had good perovskite structures, had particle sizes ranging from 50 to 200nm. Besides, the average size of LaCoO3 particles prepared by the microwave method was 30nm. In addition, colors and output of the products varied with the amount of the Ca-doped.Chapter 3:Perovskite-type LaCoO3 was prepared by stearic acid sol-gel method with microwave. It was used to photocatalytically degrade acid fuchsin solution. The effects of catalytic time, amount of catalyst, initial concentration of the dye and pH on degradation rate were investigated, and the reuse of the catalyst was also discussed. 90% acid fuchsin (10mg/L) could be degraded in 60min with 0.2g LaCoO3; a degradation rate above 95% was achieved in 30min in the acid fuchsin solution (pH=2). It indicated that LaCoO3 prepared by microwave had a good photocatalytic activity. In addition, acid fuchsin was degraded by the catalyst of LaCoO3 with a higher degaration rate than the basic fuchsin.Chapter 4:Over high pressure mercury lamp, the photocatalytic degradation of reactive turquoise blue KN-G and reactive brilliant blue X-BR with La1-xCaxCoO3 as photocatalyst that was prepared by stearic acid sol-gel method was investigated by using UV-Visible spectroscopy. The influence of catalyst loading, initial concentration of the dyes, the amount of the Ca-doped and light source on the degradation of the reactive turquoise blue was tested. The results showed that the photocatalytic degradation of reactive dyes varied with the amount of Ca doped, and the best photocatalytic degradation of reactive turquoise blue was observed in the system of La0.85Ca0.15CoO3, while the best photocatalytic degradation of reactive brilliant blue was obtained by La0.85Ca0.15CoO3·The reactivities of the catalyst were different under the mercury lamp and sunlight, however, the overall degradation of dyes was in the same.Chapter 5:The photocatalytic degradation of three reactive dyes, reactive dark blue B-2GLN, reactive turquoise blue KN-G and reactive brilliant blue X-BR were studied in the presence of La1-xCaxFeO3 prepared by stearic acid sol-gel method under high pressure mercury lamp. The effects of catalytic time, amount of catalyst and initial concentration of dyes on the degradation rate were discussed. It indicated that the photocatalytic degradation of the three reactive dyes varied with the amount of Ca-doped. La0.95Ca0.05FeO3 was obtained and exhibited the best photocatalytic activities. La0.85Ca0.15FeO3 also exhibited good photocatalytic activities for 5～10mg/L reactive dark blue, reactive brilliant blue or for 5～20mg/L reactive turquoise blue.更多还原