Energy transfer between terbium and europium ions in barium orthosilicate phosphors obtained from sol-gel route

Autor(es)

Bispo-, Jr., Airton G. ^{[1, 2]} ; Lima, Sergio A. M. ^{[1, 2]} ; Pires, Ana. M. ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ Unesp, Sch Technol & Sci, R Roberto Simonsen 305, BR-19060900 Presidente Prudente, SP - Brazil

^[2] Sao Paulo State Univ Unesp, Inst Biosci Humanities & Exact Sci, BR-15054000 Sao Jose Do Rio Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Luminescence; v. 199, p. 372-378, JUL 2018.
• Citações Web of Science: 11

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. (AU)

• Processo FAPESP: 16/20421-9 - Dispositivos tricromáticos a base de Ba2SiO4:Eu3+ e/ou Tb3+: síntese sol-gel e deposição eletroforética visando aplicação em LEDs brancos
• Beneficiário: Airton Germano Bispo Júnior
• Linha de fomento: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 15/10394-1 - Filmes LBL luminescentes de Ba2SiO4 dopado com terras raras obtido via sol-gel para aplicação em LEDs brancos
• Beneficiário: Airton Germano Bispo Júnior
• Linha de fomento: Bolsas no Brasil - Mestrado
• Processo FAPESP: 12/13876-9 - Efeitos ópticos e estruturais da variação da concentração do íon dopante Eu(III) na matriz Ba2SiO4 sintetizada via sol-gel
• Beneficiário: Airton Germano Bispo Júnior
• Linha de fomento: Bolsas no Brasil - Iniciação Científica