Photochromism and luminescence of tungsten and trivalent rare-earth ions-based compounds via hydrothermal synthesis

• Grant number: 13/09656-6
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): December 01, 2013
• Effective date (End): February 28, 2015
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Inorganic Chemistry
• Valor Concedido/Desembolsado (R$): 29,172.66 / 29,172.66
• Principal Investigator: Ana Maria Pires
• Grantee: Josiane Aparecida Sobrinho
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

Matrix systems doped with rare earth elements have many applications, which are mainly due to the magnetic and spectroscopic properties of these elements. The Eu(III) ions are widely known and used as spectroscopic probes because of their optical properties; Pr(III) ions have excited state lifetimes relatively short, important for many applications. Tungsten-based compounds, in turn, form a large class of inorganic functional materials which exhibit interesting physical properties. These materials have potential application in the field of optical materials, catalysts, among others, which make them subject of several studies and applications. Due to W(VI) ions high density, compounds based on them may be considered potentially applicable as scintillators. Scintillator materials are able to absorb high energy radiation, called ionizing radiation, and convert it efficiently into radiation in the UV-Vis-IR, which allows its application in high-energy physics, industrial inspection, dosimetry, nuclear medicine and radiation detection for medical diagnosis. Among the compounds of W(VI), highlights the oxy-hydroxide tungsten and lanthanide ions, with formula LnW2O6(OH)3, about which are a few reports in the literature. The phase is easily synthesized through hydrothermal method, a synthetic route that occurs at much lower temperatures compared to other methods and enables phase, size and morphology control of the products simply by manipulating the concentration and molar ratio of reactants, pH and temperature. Thus, the objective of this study is to evaluate the structural and spectroscopic properties of oxy-hydroxides tungsten and trivalent rare earth cations synthesized by hydrothermal route.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SOBRINHO, JOSIANE A.; MONTEIRO, JORGE H. K. S.; DAVOLOS, MARIAN R.; CEBIM, MARCO A.; PIRES, ANA M.. Photoluminescence and Scintillation Modulation Upon UV/X-ray-Induced Photochromism in Europium Tungstate Phosphors. CHEMISTRYSELECT, v. 2, n. 12, p. 3538-3548, APR 24 2017. (13/09656-6)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

SOBRINHO, Josiane Aparecida. Fotocromismo e luminescência de compostos a base de tungstênio e íons terras raras trivalentes via síntese hidrotérmica. 2015. Master's Dissertation - Universidade Estadual Paulista (Unesp). Instituto de Química. Araraquara Araraquara.