Use este identificador para citar o ir al link de este elemento: http://hdl.handle.net/1843/62086
Tipo: Artigo de Periódico
Título: Polymorphism in Gd2Ge2O7 ceramics: structural, vibrational, and optical features
Autor(es): Guilherme Mendes Martins
Cristiano Fantini Leite
Roberto Luiz Moreira
Anderson Dias
Resumen: In this work, Gd2Ge2O7 polymorphs were obtained by solid-state reactions at 1100–1300 °C. Structural and vibrational features were investigated by X-ray diffraction and Raman spectroscopy. For the triclinic (space group P1) polymorph, all the predicted phonons were discerned in perfect agreement with the group theory calculations, while for the tetragonal polymorph (space group P41212), 53 bands of the 81 predicted modes could be identified and characterized. The Gd3+ 4f-4f electronic transitions were investigated by diffuse reflectance spectroscopy in the range 200–340 nm. By applying the Kubelka-Munk function, it was possible to determine the bandgap values for all ceramics studied. The tetragonal polymorph exhibited higher bandgap values (5.88 eV) than the triclinic one (5.59 eV), which are both more energetic than other pyrochlore polymorphs reported in the literature. The results indicate that the presence of polymorphism in Gd2Ge2O7 ceramics can be used to produce tailor-made materials since their crystal structures have a strong influence on their optical properties. Consequently, these properties could be used to tuning the optical properties of Gd-containing materials to sensitize and transfer energy to other luminescent lanthanide ions, aiming for innovative applications.
Asunto: Polimorfismo (Cristalografia)
Terras raras
Raman, Espectroscopia de
Espectrometria de ultra violeta
Espectros vibracionais
Metais de terras raras
Fotoluminescência
Compostos de lantânio
Idioma: eng
País: Brasil
Editor: Universidade Federal de Minas Gerais
Sigla da Institución: UFMG
Departamento: ICX - DEPARTAMENTO DE FÍSICA
ICX - DEPARTAMENTO DE QUÍMICA
Tipo de acceso: Acesso Restrito
Identificador DOI: https://doi.org/10.1016/j.ceramint.2021.02.082
URI: http://hdl.handle.net/1843/62086
Fecha del documento: 2021
metadata.dc.url.externa: https://www.sciencedirect.com/science/article/pii/S0272884221004302
metadata.dc.relation.ispartof: Ceramics International
Aparece en las colecciones:Artigo de Periódico

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