高活性TiO_2-LaFeO_3复合纳米材料的合成及其可见光催化性能  

Synthesis of TiO_2-LaFeO_3 composite nanomaterials with high active and its visible photocatalytic activity

作　　者：孟庆强[1] 孙婉婷[1] 栾云博[1] 井立强[1] 

机构地区：[1]黑龙江大学化学化工与材料学院,哈尔滨150080

出　　处：《黑龙江大学自然科学学报》2013年第5期617-622,共6页Journal of Natural Science of Heilongjiang University

基　　金：国家自然科学基金资助项目(21071048)

摘　　要：利用硅烷偶联剂KH550调制的柠檬酸溶胶-水热法制备了高活性的LaFeO3纳米粒子,同时利用简单的湿化学法进一步构建了TiO2-LaFeO3纳米复合物。并通过XRD、IR、SPS等方法对样品进行了表征。重点研究了硅引入量对LaFeO3粒子尺寸的影响以及不同比例复合对TiO2-LaFeO3样品活性的影响。结果表明,可控合成LaFeO3的关键在于所生成的SiO2起到有效抑制粒子长大的作用。适量硅的引入显著地提高了LaFeO3纳米粒子的可见光催化活性,这与其具有小粒子尺寸、大比表面积有关。并且适当复合比例的TiO2-LaFeO3样品的光催化活性得到提高,这可能是由于二者之间有效复合形成了异质结,从而使得光生载流子的分离状况得到改善。LaFeO3 nanoparticles with a high activity have been synthesized by a silane coupling agent （KH550） modified citrate sol-hydrothermal method. TiO2-LaFeO3 composites were also prepared by a simple wet chemical method. These samples were characterized by XRD, FT-IR and SPS. The effects of the silicon introduction on the LaFeO3 particle size and the effects of TiO2 content on the photocatalytie activity of TiO2-LaFeO3 have been investi- gated, respectively. The results showed that SiO2 played an important role in inhibiting growth of LaFeO3 particles effectively, and an appropriate amount of Si improved the photocatalytic activity of LaFeO3 significantly due to its small particle size and large specific surface area. In addition, the photocatalytic activity of TiOz-LaFeO3 compos- ites was further enhanced via coupled with an appropriate amount of TiO2, which was attributed to the formation of heterojunction and the effective separation of photo-generated charge carriers.

关 键 词：TiO2-LaFeO3复合氧化物 可见光催化 硅烷偶联剂 

分 类 号：O643[理学—物理化学]