Self-assembled three-dimensional NaY(WO4)2:Ln3+ architectures: Hydrothermal synthesis, growth mechanism and luminescence properties

• Published in: Journal of alloys and compounds Vol. 529; pp. 140 - 147
• Main Authors: Huang, Shaohua, Wang, Dong, Wang, Yan, Wang, Liuzhen, Zhang, Xiao, Yang, Piaoping
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.07.2012; Elsevier
• Subjects: Chemical synthesis methods; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Hydrothermal; Materials science; Methods of nanofabrication; Nanocrystals and nanoparticles; NaY(WO4)2; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures; Physics; Three-dimensional; Up-conversion; Three-dimensional; NaY(WO4)2; Hydrothermal; Up-conversion; Particle size; NaY(WO; Sodium Yttrium Tungstates Mixed; Doping; Photoluminescence; Frequency conversion; ); Self-assembled layers; XRD; Heat treatments; Nanoparticles; Template method; Energy-level transitions; Hydrothermal synthesis; Growth mechanism; Rare earth additions; Chromaticity; Microstructure; Nanomaterial synthesis
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2012.02.156

Self-assembled 3D NaY(WO4)2:Ln3+ hierarchical microstructures with multicolor DC and UC luminescence were synthesized through a hydrothermal process and followed by a subsequent heat treatment process. [Display omitted] ► Novel self-assembled 3D NaY(WO4)2:Ln are prepared by a chemical conversion method without using any surfactant or catalyst. ► Under UV excitation, the precursor of NaY(WO4)2:Eu3+ exhibits interesting white light emission. ► The as-annealed NaY(WO4)2:Ln3+ architectures exhibit multicolor DC and UC luminescences. ► The possible formation mechanism is well investigated. Novel three-dimensional (3D) flower-like NaY(WO4)2:Ln3+ (Ln=Eu, Yb/Er, Yb/Tm and Yb/Ho) microstructures with uniform shape and dimension have been prepared using Y(OH)CO3 nanospheres as sacrificial template through a hydrothermal process and followed by a subsequent heat treatment process. The whole process was carried out in aqueous condition without using any organic solvents, surfactant, or catalyst. The phase, morphology, size, and photoluminescence (PL) properties were well characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL) spectra, and kinetic decays, respectively. The results reveal that the as-prepared precursor of NaY(WO4)2:Eu3+ exhibits interesting white light emission under UV excitation. After annealing, the as-obtained 3D flower-like NaY(WO4)2:Eu3+ microstructures show exclusively red (Eu3+, 5D0→7F2) luminescence. Furthermore, the up-conversion (UC) luminescent properties and the emission mechanisms of NaY(WO4)2:Yb3+/Ln3+ (Ln=Er, Tm, Ho) microstructures have been systematically studied, which show respective green (Er3+, 4S3/2, 2H11/2→4I15/2), blue (Tm3+, 1G4→3H6) and yellow-green (Ho3+, 5S2→5I8) luminescence under 980nm NIR excitation.