Effect of metal ion-doping on characteristics and photocatalytic activity of Ti02 nanotubes for removal of humic acid from water  

作　　者：Rongfang YUAN 

机构地区：[1]Key Laboratory of Educational Ministry for High Efficient Mining and Safety in Metal Mine, University of Science and Technology Beijing, Beijing 100083, China [2]Department of Environmental Engineering, Scl~ool of Civil and-Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China

出　　处：《Frontiers of Environmental Science & Engineering》2015年第5期850-860,共11页环境科学与工程前沿（英文）

基　　金：We gratefully acknowledge the financial support from the National Natural Science Foundation of China （Grant No. 51178043）.

摘　　要：The effect of ion-doping on TiO2 nanotubes were investigated to obtain the optimal TiO2 nanotubes for the effective decomposition of humic acids （HA） through O3/UV/ion-doped TiO2 process. The experimental results show that changing the calcination temperature, which changed the weight fractions of the anatase phase, the average crystallite sizes, the Brunauer-Emmett-Teller sur- face area, and the energy band gap of the catalyst, affected the photocatalytic activity of the catalyst. The ionic radius, valence state, and configuration of the dopant also affected the photocatalytic activity. The photocatalytic activities of the catalysts on HA removal increased when Ag＋, AP＋, Cu2＋, Fe3＋, V5 ＋, and Zn2＋ were doped into the TiO2 nanotubes, whereas such activities decreased as a result of Mn2＋- and Ni2＋-doping. In the presence of 1.0 at.% Fe3＋- doped TiO2 nanotubes calcined at 550℃, the removal efficiency of HA was 80% with a pseudo-first-order rate constant of 0.158 min-. Fe3＋ in TiO2 could increase the generation of OH, which could remove HA. However, Fe3＋ in water cannot function as a shallow trapping site for electrons or holes.The effect of ion-doping on TiO2 nanotubes were investigated to obtain the optimal TiO2 nanotubes for the effective decomposition of humic acids （HA） through O3/UV/ion-doped TiO2 process. The experimental results show that changing the calcination temperature, which changed the weight fractions of the anatase phase, the average crystallite sizes, the Brunauer-Emmett-Teller sur- face area, and the energy band gap of the catalyst, affected the photocatalytic activity of the catalyst. The ionic radius, valence state, and configuration of the dopant also affected the photocatalytic activity. The photocatalytic activities of the catalysts on HA removal increased when Ag＋, AP＋, Cu2＋, Fe3＋, V5 ＋, and Zn2＋ were doped into the TiO2 nanotubes, whereas such activities decreased as a result of Mn2＋- and Ni2＋-doping. In the presence of 1.0 at.% Fe3＋- doped TiO2 nanotubes calcined at 550℃, the removal efficiency of HA was 80% with a pseudo-first-order rate constant of 0.158 min-. Fe3＋ in TiO2 could increase the generation of OH, which could remove HA. However, Fe3＋ in water cannot function as a shallow trapping site for electrons or holes.

关 键 词：TiO2 nanotubes ion-doping humic acids pseudo-first-order mechanism 

分 类 号：O643.36[理学—物理化学] TB383[理学—化学]