Publicação: Energy transfer between terbium and europium ions in barium orthosilicate phosphors obtained from sol-gel route
Carregando...
Arquivos
Data
Orientador
Coorientador
Pós-graduação
Curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Editor
Elsevier B.V.
Tipo
Artigo
Direito de acesso
Acesso aberto

Resumo
The present paper reports on the energy transfer mechanism between Eu3+ and Tb3+ in barium orthosilicate obtained from the sol-gel route, when both activators concentration is varied. The synthetic methodology was adjusted to provide high crystalline and monophasic Ba2SiO4. In the emission spectra under 250 nm excitation, both Eu3+ (D-5(0)-> F-7(J)) and Tb3+ (D-5(3)-> F-7(J) and D-5(4)-> F-7(J)) transitions can be observed at low Eu3+ doping concentrations with an unexpected and intense blue emission from Tb3+. However, when the Eu3+ content is higher than that of the Tb3+, just the Eu3+ emission is noticed. Also, it is possible to tune the phosphor emission from red to pink by varying the Eu3+ and Tb3+ content. From the excitation spectra, we inferred that energy transfer (ET) from Tb3+ to Eu3+ occurs at any doping situation, nonetheless, the opposite process happens just when both activators amount is similar. An approach using the Tb3+ and Eu3+ lifetimes and the Eu3+ quantum efficiency confirms this observation, indicating that not only the matrix act as sensitizer to the Eu3+ ions, but also Tb3+ ions contribute by increasing the Eu3+ quantum efficiency in up to 20%. Finally, by using the Van Uitert theory, it was found for this system that the ET between the two rare-earth ions is dominated by the dipole-dipole mechanism.
Descrição
Palavras-chave
Silicate, Europium, Terbium, Energy transfer, Van Uitert theory, Spectroscopic probe
Idioma
Inglês
Como citar
Journal Of Luminescence. Amsterdam: Elsevier Science Bv, v. 199, p. 372-378, 2018.