Luminescent Terbium Doped Aluminate Particles: Properties and Surface Modification with Asparagine

Author(s)

Caiut, Jose M. A. ^{[1, 2]} ; Messaddeq, Younes ^[1] ; Dexpert, Herve ^[2] ; Verelst, Marc ^[2] ; Ribeiro, Sidney J. L. ^[1] ; Dexpert-Ghys, Jeannette ^[2]

Affiliation

^[1] Univ Estadual Paulista UNESP, Inst Quim, BR-14801970 Araraquara, SP - Brazil

^[2] CNRS, Ctr Mat Elaborat & Struct Studies, F-31055 Toulouse 4 - France

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 26, n. 12, p. 2536-2544, DEC 2015.
• Web of Science Citations: 0

Abstract

New luminescent organic-inorganic hybrid particles based on Tb-doped aluminates and asparagine (Asn) surface modifiers were investigated. The Tb3+ doped inorganic core was obtained by spray pyrolysis, at 200 ºC γ-AlOOH (BOE:Tbx%) or at 700 ºC γ-Al2O3 (γTA:Tbx%). The reaction of Asn with boehmite in water disaggregated the sub-micronic boehmite particles to give stable dispersion of surface modified nanoparticles Asn:BOE:Tbx% (x = 1 or 5). Concerning the Asn:γTA:Tbx% system, an Asn film wrapping alumina particles was observed. Photoluminescence spectra exhibited the bands assigned to Tb3+5D4 → 7FJ = 6-3 transitions. A broad absorption band (240 nm) was assigned to the host (aluminate) to ion (Tb3+) energy transfer. Efficient energy transfer was observed when active ions are incorporated in the defect-spinel structure of γTA, whereas it was relatively weak for BOE:Tb where Tb3+ are bonded to the hydroxyls groups at nanocrystals surface. It is noticeable that Asn strengthens the linkage of Tb3+ with the aluminate matrix, enhancing the host to dopant energy transfer. (AU)

• FAPESP's process: 11/21551-0 - Bio-compatible luminescent nanoparticles: synthesis, characterization and applications
• Grantee: José Maurício Almeida Caiut
• Support Opportunities: Regular Research Grants