X-ray Photoelectron and Absorption Spectroscopy of Metal-Rich Phosphides M2P and M3P (M = Cr−Ni)

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• 作者：Peter E. R. Blanchard ; Andrew P. Grosvenor ; Ronald G. Cavell ; Arthur Mar
• 刊名：Chemistry of Materials
• 出版年：2008
• 出版时间：November 25, 2008
• 年：2008
• 卷：20
• 期：22
• 页码：7081-7088
• 全文大小：340K
• 年卷期：v.20,no.22(November 25, 2008)
• ISSN：1520-5002

文摘

The electronic structures of metal-rich binary phosphides M₂P and M₃P (M = Cr−Ni) have been examined by means of X-ray photoelectron and absorption spectroscopy and compared with those of the monophosphides MP. The P 2p_3/2 binding and P K-edge absorption energies decrease with greater ionic character of the M−P bonding and indicate the presence of anionic phosphorus, contrary to previous theoretical assertions but consistent with our previous results. Interatomic effects play a more important role in affecting the energy shifts in these metal-rich phosphides than in the monophosphides, becoming more pronounced with higher metal concentration. Although the M 2p_3/2 XPS spectra show no discernible shifts in binding energies, they reveal satellite features whose intensity can be related to metal charge in the Co- and Ni-containing phosphides. In these cases, the metal charge becomes less positive with higher metal concentration. For Ni₂P and Ni₃P, this trend was confirmed from an analysis of the Ni L-edge and M-edge XANES spectra.