New Methodological Approach for the Vanadium K-Edge X-ray Absorption Near-Edge Structure Interpretation: Application to the Speciation of Vanadium in Oxide Phases from Steel Slag

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• 作者：Perrine Chaurand ; Jé ; rô ; me Rose ; Valé ; rie Briois ; Murielle Salome ; Olivier Proux ; Vivian Nassif ; Luca Olivi ; Jean Susini ; Jean-Louis Hazemann ; Jean-Yves Bottero
• 刊名：Journal of Physical Chemistry B
• 出版年：2007
• 出版时间：May 17, 2007
• 年：2007
• 卷：111
• 期：19
• 页码：5101 - 5110
• 全文大小：225K
• 年卷期：v.111,no.19(May 17, 2007)
• ISSN：1520-5207

文摘

This paper presents a comparison between several methods dedicated to the interpretation of V K-edge X-rayabsorption near-edge structure (XANES) features. V K-edge XANES spectra of several V-bearing standardcompounds were measured in an effort to evaluate advantages and limits of each method. The standardcompounds include natural minerals and synthetic compounds containing vanadium at various oxidation state(from +3 to +5) and in different symmetry (octahedral, tetrahedral, and square pyramidal). Correlationsbetween normalized pre-edge peak area and its centroid position have been identified as the most reliablemethod for determining quantitative and accurate redox and symmetry information for vanadium. Thismethodology has been previously developed for the Fe K edge. It is also well adapted for the V K edge andis less influenced by the standard choice than other methods. This methodology was applied on an"environmental sample," i.e., a well-crystallized leached steel slag containing vanadium as traces. Micro-XANES measurements allowed elucidating the microdistribution of vanadium speciation in leached steelslag. The vanadium exhibits an important evolution from the unaltered to the altered phases. Its oxidationstate increases from +3 to +5 together with the decrease of its symmetry (from octahedral to tetrahedral).