BiOCl/BiVO4 p–n Heterojunction with Enhanced Photocatalytic Activity under Visible-Light Irradiation

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• 作者：Zhiqiao He ; Yuanqiao Shi ; Chao Gao ; Lina Wen ; Jianmeng Chen ; Shuang Song
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：January 9, 2014
• 年：2014
• 卷：118
• 期：1
• 页码：389-398
• 全文大小：488K
• ISSN：1932-7455

文摘

A novel visible-light-active BiOCl/BiVO₄ photocatalyst with a p鈥搉 heterojunction structure was prepared using a hydrothermal method. The photocatalytic activity of the heterojunction was investigated by monitoring the change in methyl orange (MO) concentration under visible-light irradiation. The results reveal that the composite exhibited markedly improved efficiency for MO photodegradation in comparison with pure BiVO₄, BiOCl, and Degussa P25. This is ascribed to the B-type heterojunction structure with a strong oxidative ability and efficient charge separation and transfer across the BiOCl/BiVO₄ p鈥搉 junction. The highest activity was obtained in the BiOCl/BiVO₄ heterojunction using a composite of 13 mol % BiOCl and 87 mol % BiVO₄. The removal of MO was mainly initiated by valence-band holes, but dissolved oxygen also played a crucial role in consuming the conduction-band electrons. This was verified by the effects of scavengers and N₂ purging.