Effects of the Pechini's modified synthetic route on structural and photophysical properties of Eu3+ or Tb3+-doped LaAlO3

Herein, it is reported the Pechini's synthesis of LaAlO3:Ln3+ (Ln = Eu3+ or Tb3+) varying doping concentration from 1 to 9 at.% to evaluate its influence on structure and luminescence. Sub-micrometric, high-crystalline and monophasic samples with crystallite size smaller than 61 nm were synthes...

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Detalles Bibliográficos
Autores: Garcia, A. B.S. [UNESP], Bispo-Jr, A. G., Lima, S. A.M. [UNESP], Pires, A. M. [UNESP]
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:Brasil
Institución:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/221921
Acceso en línea:http://dx.doi.org/10.1016/j.materresbull.2021.111462
http://hdl.handle.net/11449/221921
Access Level:acceso abierto
Palabra clave:Eu(III) and Tb(III) doping ions
Lanthanum aluminate
Luminescent nanoparticles
Perovskite host lattice
Red and green phosphors
Descripción
Sumario:Herein, it is reported the Pechini's synthesis of LaAlO3:Ln3+ (Ln = Eu3+ or Tb3+) varying doping concentration from 1 to 9 at.% to evaluate its influence on structure and luminescence. Sub-micrometric, high-crystalline and monophasic samples with crystallite size smaller than 61 nm were synthesized with activators replacing slightly-distorted LaO12 polyhedra, and occupying two non-equivalent local sites on the surface, and inside them. Upon UV excitation, Eu3+-doped phosphors emit at 620 nm while Tb3+ ones exhibit dominant wavelength within the green spectral region. The excited state lifetimes lie within 2.5–3.4 ms, and as doping percentage increases, luminescence quenching mediated by exchange coupling energy transfer occurs, leading to the 3 and the 7% as the optimal Eu3+ and Tb3+concentrations, respectively. Finally, our proposed route increases the Eu3+ 5D0→7F2 transition relative intensity, compared with others reported, ensuring that this method brings a breakthrough in the optical performance of LaAlO3-based phosphors.