Effect of dopant concentration on photocatalytic activity of TiO2 film doped by Mn non-uniformly

• Autorzy: Kaijian Zhang , Wei Xu , Xinjun Li , Shaojian Zheng , Gang Xu
• Języki publikacji: EN

Abstrakty

EN

The thin films of TiO2 doped by Mn non-uniformly were prepared by sol-gel method under process control. In our preceding study, we investigated in detail, the effect of doping mode on the photocatalytic activity of TiO2 films showing that Mn non-uniform doping can greatly enhance the activity. In this study we looked at the effect of doping concentration on the photocatalytic activity of the TiO2 films. In this paper, the thin films were characterized by UV-vis spectrophotometer and electrochemical workstation. The activity of the photocatalyst was also evaluated by photocatalytic degradation rate of aqueous methyl orange under UV radiation. The results illustrate that the TiO2 thin film doped by Mn non-uniformly at the optimal dopant concentration (0.7 at %) is of the highest activity, and on the contrary, the activity of those doped uniformly is decreased. As a comparison, in 80 min, the degradation rate of methyl orange is 62 %, 12 % and 34 % for Mn non-uniform doping film (0.7 at %), the uniform doping film (0.7 at %) and pure titanium dioxide film, respectively. We have seen that, for the doping and the pure TiO2 films, the stronger signals of open circuit potential and transient photocurrent, the better photocatalytic activity. We also discusse the effect of dopant concentration on the photocatalytic activity of the TiO2 films in terms of effective separation of the photon-generated carriers in the semiconductor.

Słowa kluczowe

EN

TiO2; Mn; dopant concentration; non-uniform

• Czasopismo: Open Chemistry
• Rocznik: 2006
• Tom: 4
• Numer: 2
• Strony: 234-245

Daty

wydano

2006-06-01

online

2006-06-01

Twórcy

autor

Kaijian Zhang

autor

Wei Xu

• Institute Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, 510640, Guangzhou, People Republic of China

autor

Xinjun Li

• Institute Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, 510640, Guangzhou, People Republic of China,

autor

Shaojian Zheng

• Institute Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, 510640, Guangzhou, People Republic of China

autor

Gang Xu

• Institute Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, 510640, Guangzhou, People Republic of China

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Identyfikatory

DOI

10.2478/s11532-006-0010-8