Enhanced photocatalytic degradation of methyl orange by CdS quantum dots sensitized platelike WO3 photoelectrodes
来源期刊：中南大学学报(英文版)2015年第12期
论文作者：WEN Jin LIU Can-jun DU Yong HU Chuan-yue TIAN Xiu-ying
文章页码：4551 - 4559
Key words：photocatalytic degradation; cadmium sulfide; platelike WO3; photoelectrode; Nano-TiO2 buffer layer
Abstract: CdS quantum dots sensitized platelike WO3 photoelectrodes were successfully synthesized by a facile hydrothermal method and a modified chemical bath deposition (CBD) technique. To further improve the stability of the photoelectrodes in alkaline environment, the platelike WO3 films were treated with TiCl4 to form a nano-TiO2 buffer layer on the WO3 plate surface before loading CdS QDs. The resulting electrodes were characterized by using XRD, SEM, HR-TEM and UV-vis spectrum. The photocatalytic activity of the resulting electrodes was investigated by degradation of methyl orange (MO) in aqueous solution. The photoelectrochemical (PEC) property of the resulting electrodes was also characterized by the linear sweep voltammetry. The results of both the degradation of MO and photocurrent tests indicated that the as-prepared CdS QDs sensitized WO3 platelike photoelectrodes exhibit a significant improvement in photocatalytic degradation and PEC activity under visible light irradiation, compared with unsupported CdS QDs electrodes. Significantly, coating the WO3 plates with nano-TiO2 obviously facilitate the charge separation and retards the charge-pair recombination, and results in a highest activity for QDs CdS/TiO2/WO3 photoelectrodes.
WEN Jin(文瑾)1, 2, LIU Can-jun(刘灿军)3, DU Yong(杜勇)1, HU Chuan-yue(胡传跃)2, TIAN Xiu-ying(田修营)2
(1. Power Metallurgy Research Institute, Central South University, Changsha 410083, China;
2. Department of Chemistry and Material Science, Hunan University of Humanities, Science and Technology,
Loudi 417600, China;
3. School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China)
Abstract:CdS quantum dots sensitized platelike WO3 photoelectrodes were successfully synthesized by a facile hydrothermal method and a modified chemical bath deposition (CBD) technique. To further improve the stability of the photoelectrodes in alkaline environment, the platelike WO3 films were treated with TiCl4 to form a nano-TiO2 buffer layer on the WO3 plate surface before loading CdS QDs. The resulting electrodes were characterized by using XRD, SEM, HR-TEM and UV-vis spectrum. The photocatalytic activity of the resulting electrodes was investigated by degradation of methyl orange (MO) in aqueous solution. The photoelectrochemical (PEC) property of the resulting electrodes was also characterized by the linear sweep voltammetry. The results of both the degradation of MO and photocurrent tests indicated that the as-prepared CdS QDs sensitized WO3 platelike photoelectrodes exhibit a significant improvement in photocatalytic degradation and PEC activity under visible light irradiation, compared with unsupported CdS QDs electrodes. Significantly, coating the WO3 plates with nano-TiO2 obviously facilitate the charge separation and retards the charge-pair recombination, and results in a highest activity for QDs CdS/TiO2/WO3 photoelectrodes.
Key words:photocatalytic degradation; cadmium sulfide; platelike WO3; photoelectrode; Nano-TiO2 buffer layer
