Origin of Photocatalytic Activation of Silver Orthophosphate from First-Principles

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• 作者：Xinguo Ma ; Bin Lu ; Di Li ; Rui Shi ; Chenshi Pan ; Yongfa Zhu
• 刊名：Journal of Physical Chemistry C
• 出版年：2011
• 出版时间：March 24, 2011
• 年：2011
• 卷：115
• 期：11
• 页码：4680-4687
• 全文大小：969K
• 年卷期：v.115,no.11(March 24, 2011)
• ISSN：1932-7455

文摘

First-principles density functional theory incorporating the LDA + U formalism has been used to investigate the origin of photocatalytic activation of Ag₃PO₄. The approach provides an improved band gap and the position of the valence band if both U_p and U_d are used. Through examining the energy band structure and density of states, we can understand why Ag₃PO₄ is a promising photocatalyst for oxidizing water as well as degrading organic contaminants. The results show that Ag₃PO₄ has a large dispersion of conduction band and the inductive effect of PO₄^{3鈭?/sup>, which help the separation of electron鈭抙ole pairs. It is demonstrated theoretically that Ag vacancies in Ag₃PO₄ with high concentration have a significant effect on the separation of electron鈭抙ole pairs and optical absorbance in the visible-light region. These findings present a reasonable explanation of recent experimental results.}