聚合物前驱体法制备光催化剂Sr_2Bi_2O_5及其光催化性能的研究  

Synthesis of photocatalyst Sr_2Bi_2O_5 by the polymerized complex method and study of its photocatalytic activity

作　　者：陈龙[1] 叶红齐[1] 唐新德[1] 

机构地区：[1]中南大学化学化工学院,湖南长沙410083

出　　处：《现代化工》2010年第11期40-43,共4页Modern Chemical Industry

基　　金：高等学校博士学科点专项科研基金(200805330032)

摘　　要：以Bi(NO3)3.5H2O、Sr(NO3)2为原料,采用柠檬酸为金属配位剂、水为溶剂、乙二醇为酯化剂,通过聚合物前驱体法(PC)制备了光催化剂Sr2Bi2O5粉体。研究了Sr2Bi2O5晶相的形成过程,并对光催化剂的表面形貌、比表面积和光吸收性能进行了分析。以可见光下亚甲基蓝的光催化降解为模型反应,考察了光催化剂的催化性能。结果表明,在700℃下煅烧1 h即可制备具有正斜方晶型的Sr2Bi2O5。相对于传统固相反应法(SSR),聚合物前驱体法制备的光催化剂粒径小,比表面积大,光吸收性能有所增强。光催化实验表明,聚合物前驱体法制备的Sr2Bi2O5对亚甲基蓝的降解率为95.8%,明显优于固相法制备的Sr2Bi2O5(降解率为46.7%)。实验还研究了催化剂用量和催化时间对降解效率的影响。Photocatalyst Sr2Bi2O5 powders are synthesized by the polymerized complex （PC） method with Bi （NO3 ）3 ·5H2O and Sr（ NO3 ）2 as raw materials, citric acid as chelating agent, water as solvent and ethylene alcohol as etherification agent. The evolution of Sr2Bi2O5 crystal phase is investigated. The surface morphology, specific surface area and optical characteristics are also analyzed. The photocatalytic activity of the photocatalyst is evaluated with methylene blue as simulated compound under the visible light irradiation（ A 〉400 nm）. The results show that the pure orthorhombie Sr2Bi2O5 is obtained by calcined at 700℃ for 1 hour. The photocatalyst prepared by the polymerized complex method exhibits smaller particle size, bigger specific surface area and better optical characteristics than samples synthesized by the soild-state reaction（SSR） method. The degradation rate of methylene blue by Sr2Bi2O5 （PC） is up to 95.8% ,which is much higher than that of Sr2Bi2O5 synthesized by solid-state reaction method. The effects of the photocatalyst concentration and the illumination time on the degradation rate are also discussed.

关 键 词：Sr2Bi2O5 聚合物前驱体法 光催化 降解 亚甲基蓝 

分 类 号：O643.36[理学—物理化学]