摘要
以绢云母为载体,采用水解-沉淀法制备出了绢云母负载纳米TiO2粉体(TiO2/M),以尿素为氮源,采用后掺杂法制得具有可见光响应的N掺杂TiO2/M.采用XRD,XPS,SEM,DUV等手段对样品进行了性能表征;并以日光色镝灯为光源,甲基橙为模拟污染物检测其光催化活性.研究了N的掺杂对粉体中TiO2晶相结构,粒度和光催化性能的影响.结果表明,绢云母与TiO2通过桥氧相连形成包覆层,N的掺杂抑制了TiO2晶粒的长大,减缓锐钛矿向金红石相的转变,同时N的掺杂形成Ti—O—N键,形成新的能级结构,使样品对光的吸收边红移至440—550 nm,具有明显的可见光响应,对甲基橙的光催化降解率与没有掺N的样品相比,最高可达1.6倍.
N-doped TiO2/mica samples were directly prepared by hydrolysis-precipitation method,where mica was used as the base and urea was the resource of N.The as-prepared samples showed photocatalytic activity under visible light.The samples were characterized by XRD,XPS,SEM and DUV methods.The photocatalytic activity of the samples were tested in the degradation of methyl orange using the solar dysprosium-color as light source.The results show that the formation of TiO2 film on mica was assisted by oxygen bridges.N-doping prevents the grain growth and inhibits the phase transformation from anatase to rutile.N-doping forms a new energy level above the valence band of TiO2 which extends the adsorption edge of the material to 440—550nm,showing obvious photocatalytic activity under visible light.The photocatalytic degradation rate of methyl orange was 1.6 times higher than those samples without N-doping.
出处
《环境化学》
CAS
CSCD
北大核心
2011年第2期476-482,共7页
Environmental Chemistry
基金
教育部博士后基金(20080430758)
安徽省教育厅重大科技项目(2009AJZR0081)资助
关键词
二氧化钛
绢云母
水解-沉淀
氮掺杂
光降解
TiO2
mica
hydrolysis-precipitation
nitrogen-doped
photo degradation
