Application of EPR spectroscopy for elucidation of vanadium speciation in VOx/ZrO2 catalysts subject to redox treatment

被引：65
作者：
Adamski, A [1 ]
Spalek, T [1 ]
Sojka, Z [1 ]
机构：
[1] Jagiellonian Univ, Fac Chem, PL-30060 Krakow, Poland
来源：
RESEARCH ON CHEMICAL INTERMEDIATES | 2003年 / 29卷 / 7-9期
关键词：
EPR; simulation; speciation; vanadium; zirconia; genetic algorithm;
D O I：
10.1163/156856703322601807
中图分类号：
O6 [化学];
学科分类号：
0703 ;
摘要：
Application of EPR spectroscopy corroborated by spectra simulation in speciation studies of the tetravalent vanadium in supported VOx/ZrO2 catalyst has been discussed. Implementation of genetic algorithms into automated analysis of the EPR spectra has greatly improved the simulation efficiency. The performance of the new procedure has been benchmarked against common simplex method using the multi-component model and real EPR spectra of tetravalent vanadium in VOx/ZrO2 catalysts. The analysis has revealed speciation of vanadium into surface isolated and clustered vanadyl entities and isolated bulk V-Zr(x) ions due to formation of Zr1-xVxO2 solid solution in the near to surface region. The structural heterogeneity of vanadium can be controlled by the calcination temperature and the redox treatment.
引用
收藏
页码：793 / 804
页数：12
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