Different origins of green-light photoluminescence emission in structurally ordered and disordered powders of calcium molybdate
Contribuinte(s) |
Universidade Estadual Paulista (UNESP) |
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Data(s) |
20/05/2014
20/05/2014
25/09/2008
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Resumo |
A strong greenish-light photoluminescence (PL) emission was measured at room temperature for disordered and ordered powders of CaMoO4 prepared by the polymeric precursor method. The structural evolution from disordered to ordered powders was accompanied by XRD. Raman spectroscopy, and TEM imagery. High-level quantum mechanical calculations in the density functional framework were used to interpret the formation of the structural defects of disorder powders in terms of band diagram and density of states. Complex cluster vacancies [MoO3 center dot V-O(z)] and [CaO7 center dot V-O(z)] (where V-O(z) = V-O(X), V-O(center dot), V-O(center dot center dot)) were suggested to be responsible to the appearance of new states shallow and deeply inserted in the band gap. These defects give rise to the PL in disordered powders. The natural PL emission of ordered CaMoO4 was attributed to an intrinsic slight distortion of the [MoO4] tetrahedral in the short range. |
Formato |
8920-8928 |
Identificador |
http://dx.doi.org/10.1021/jp801587w Journal of Physical Chemistry A. Washington: Amer Chemical Soc, v. 112, n. 38, p. 8920-8928, 2008. 1089-5639 http://hdl.handle.net/11449/8605 10.1021/jp801587w WOS:000259341900007 |
Idioma(s) |
eng |
Publicador |
Amer Chemical Soc |
Relação |
Journal of Physical Chemistry A |
Direitos |
closedAccess |
Tipo |
info:eu-repo/semantics/article |