MoO_3改性的TiO_2在可见光下催化降解亚甲基蓝  

Photocatalytic degradation of methylene blue by MoO_3 modified TiO_2 under visible light

作　　者：杨华博 李翔[1,2] 王安杰[1,2] 王瑶 陈永英 

机构地区：[1]大连理工大学化工学院精细化工国家重点实验室,辽宁大连116024 [2]辽宁省省级高校石油化工技术与装备重点实验室,辽宁大连116024

出　　处：《催化学报》2014年第1期140-147,共8页

基　　金：supported by the National Natural Science Foundation of China(20773020,20973030,21073022,21173033,and U1162203);the National High Technology Reaearch and Development Program of China(863 program,2008AA030803);the Program for New Century Excellent Talents in University(NCET‐04‐0275);the Fundamental Research Funds for the Central Universities(DUT13LK18);the Specialized Research Fund for the Doctral Program of Higher Education(20100041110016)~~

摘　　要：采用浸渍法制备了MoO3/P25催化剂(MoO3/P25(x),x为MoO3与P25质量比),用X射线衍射、紫外-可见漫反射光谱、傅里叶变换红外光谱及拉曼光谱等手段对样品进行了表征,并用催化降解亚甲基蓝考察了催化剂在可见光区的催化活性.结果表明,MoO3在P25表面最大单层负载量对应的MoO3与P25质量比在0.1左右.单层分散的氧化钼物种与P25之间有较强的相互作用,降低了P25禁带宽度,提高了催化剂对可见光的吸收.当MoO3与P25质量比大于0.1时,会生成晶相MoO3,催化剂对可见光的吸收反而随MoO3担载量增加而降低.催化剂禁带宽度不是决定其可见光下催化降解亚甲基蓝活性的唯一因素.具有适宜禁带宽度和一定晶相MoO3含量的MoO3/P25(0.25)表现出最佳活性.MoO3/P25 catalysts were prepared by an impregnation method.The catalysts were characterized by X-ray diffraction,ultraviolet-visible spectrophotometry,Fourier transform infrared spectroscopy,and laser Raman spectroscopy,and their photocatalytic activty was evaluated by the degradation of methylene blue dye under visible light.The monolayer dispersion threshold of MoO3 on P25 was around 0.1 g/g.The strong interaction between the monolayer-dispersed tetrahedral-coordinated molybdenum oxide species and P25 led to a decrease in the band gap of P25,thus increasing the visible light absorption of the catalyst.Crystalline MoO3 was formed on catalysts with a MoO3/P25 mass ratio above 0.1.In these cases,the visible light absorption of the catalysts decreased with increasing MoO3 content.The band gap of the catalyst was not the only factor affecting its photocatalytic activity for the degradation of methylene blue under visible light.MoO3/P25 with the MoO3 to P25 mass ratio of 0.25,which possessed not only suitable band gap but also a certain amount of crystalline MoO3,showed the best catalytic performance.

关 键 词：二氧化钛 氧化钼 等体积浸渍 亚甲基蓝 可见光 

分 类 号：O643.32[理学—物理化学] X703[理学—化学]