Vanadium-doped zircons

An illustration of this type of analysis is provided by the catalysis associated to the electrochemical oxidation of cysteine at electrodes modified with vanadium-doped zircons, V,jZrSiO4, prepared from sol-gel methodologies (Domenech and Alarcon, 2003). Figure 3.12 shows x-ray diffraction patterns for VxZrSiO4 specimens after annealing the corresponding gel precursor at 1600°C for 24 h. Here, well-defined diffraction peaks of zircon, eventually accompanied by one cristo-balite peak, appear. 

Domenech, A., and Alarcon, J. 2003. Vanadium-doped zircon and zirconia materials prepared from gel precursors as site-selective electrochemical sensors. Instrumentation, Science Technology 31, 121-139. 

Zirconium i Zr ) (/ =—5/2). The vanadium-doped zircon (V-ZrSi04) samples were studied by Si solid state, V, and Zr NMR to clarify its structure. Static Zr NMR data was reported from a pure zircon sample to quantify the amount of vanadium entering the zircon structure, and to elucidate its site preference within the lattice. 

TABLE 7-1. CRYSTALLOGRAPHIC DATA ON VANADIUM-DOPED ZIRCON POWDERS (AFTER VALENTIN, 1999)... 

In 2003, Dajda et al. used multinuclear Si, and Zr SSNMR experiments to probe the vanadium distribution in vanadium-doped zircon [44], as previous studies had provided conflicting information on doping site preferences. Although it was understood that V ions were responsible for the blue color in V-doped zircon, the authors specifically sought to... 

Friis H, Finch A, Williams C, Hanchar J (2010) Photoluminescence of zircon (ZrSi04) doped with REE (REE = Pr, Sm, Eu, Gd, Dy, Ho, Er). Phys Chem Miner 37 333-342 Friis H, Finch A, Williams C (2011) Multiple luminescent spectroscopic methods applied to the two related minerals, leucophanite and meliphanite. Phys Chem Miner 38 45-57 Gaft M (1984) Luminesctmce of vanadium containing centers in natural phosphates. Miner J 4 83-86 (in Russian)... 

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