摘要
以凹凸棒石(ATP)为载体,Ce(NO3)3.6H2O和Ti(OBu)4为原料,冰醋酸为抑制剂,采用溶胶-凝胶法制备CeO2-TiO2/ATP纳米复合材料。利用TG-DSC、TEM、XRD和N2吸附/脱附仪对复合材料进行表征,考察铈钛摩尔比对所制备样品催化降解罗丹明B溶液性能的影响。结果表明,当Ce/Ti≥5/5时,具有立方萤石结构的氧化物颗粒以固溶体形式均匀分布在ATP表面,颗粒尺寸约5～10nm;随Ti 4+的进一步增加,样品中的CeO2结晶不完全;当Ce/Ti<3/7时,样品中出现锐钛矿型TiO2的分离相。适量的Ti 4+掺杂能促进CeO2产生较多的结构缺陷,有利于增加晶格氧空位的浓度,提高样品的催化活性。对罗丹明B的催化降解实验表明,当Ce/Ti=5/5时,样品的催化性能较好,对罗丹明B溶液的化学需氧量(COD)去除率可达96%以上。
CeO2-TiO2/attapulgite（ATP）nanocomposites were prepared by the sol-gel method using ATP as support,cerium nitrate hexahydrate and tetrabutyl titanate as raw materials,glacial acetic acid as complexing agent.The microstructures of the as-prepared composites were characterized by thermogravimetric-differential scanning caloricity（TG-DSC）analysis,transmission electron microscopy（TEM）,X-ray diffraction（XRD）,and nitrogen adsorption-desorption measurements.The effects of Ce/Ti molar ratio on catalytic properties of the as-prepared composites for decomposing Rhodamine B solutions were investigated.The results indicated that when Ce/Ti was more than or equal to 5/5,CeO2-TiO2 solid solution oxide particles with cubic fluorite structure were uniformly coated on the surface of ATP with particle size of 5—10 nm.With the increase of Ti4＋ content,CeO2 nanoparticles tended to form a defective crystalline phase and existed as amorphous phase.When Ce/Ti was less than 3/7,a separated anatase TiO2 was observed in the composites.A suitable amount of Ti4＋ doping could promote the formation of structure defects,which contributed to increasing the content of oxygen vacancies and improving the catalytic activity.The catalytic efficiency of CeO2-TiO2/ATP（Ce/Ti=5/5）nanocomposite on Rhodamine B solution was higher than that of others,and the removal rate of chemical oxygen demand（COD）could reach over 96%.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2013年第7期2679-2686,共8页
CIESC Journal
基金
国家自然科学基金项目(51002016)
常州市应用基础研究计划项目(CJ20115021)
江苏省高校中青年骨干教师及校长境外研修计划项目~~
