Spray pyrolysis (SP) easily affords nano or sub-micro phosphor particles even on an industrial scale. However, control of the coordination environment around the emitting ion is inefficient, and the final solid matrix will dictate the symmetry of the emitter. Moreover, the fast heat treatment typical of SP usually results in heterogeneous symmetry sites. This paper aimed to obtain inorganic matrices incorporated with phosphors by SP while keeping the symmetry of the emitting ion unchanged along the pyrolysis process. Nanoparticles consisting of Eu-doped YVO phosphors with average diameter of 15 nm were prepared by the co-precipitation method and were subsequently incorporated into the alumina matrix by SP, to yield YVO:Eu/γ-AlO composite particles with mean size of 600 nm. X-ray powder diffraction confirmed that the vanadate particles were incorporated into the alumina matrix, and that the γ-AlO phase emerged. The band due to the [Formula: see text] → Eu transition intensified as a consequence of the incorporation of YVO:Eu into alumina-the suppression effects caused by the surface properties of the YVO:Eu phosphor nanoparticles diminished, while the structure of Eu remained unchanged in the matrix.

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Agradeço primeiramente a Deus por tornar menos penoso todos os meus caminhos. E que ao fim da minha jornada, que eu possa ter um espírito mais evoluído em amor e sabedoria. A minha família, pela constante dedicação, carinho e apoio. Gostaria de agradecer também minha namorada Aline pelo amor, paciência e companheirismo durante todos esses anos. A professora Laura Tiemi Okano, pela orientação, amizade e apoio. E por contribuir na minha formação como pessoa.