Controllable synthesis and tunable luminescence properties of Y sub(2)(WO sub(4)) sub(3):Ln super(3+) (Ln = Eu, Yb/Er, Yb/Tm and Yb/Ho) 3D hierarchical architectures

• Published in: Dalton transactions : an international journal of inorganic chemistry 2012-04, Vol.41 (18), p.5634-5642
• Main Authors: Huang, Shaohua, Zhang, Xiao, Wang, Liuzhen, Bai, Ling, Xu, Jie, Li, Chunxia, Yang, Piaoping
• Format: Article
• Language: English
• Subjects: Architecture; Doping; Emission; Luminescence; Nanostructure; Precursors; Scanning electron microscopy; Three dimensional
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c2dt30221g

Yttrium tungstate precursors with novel 3D hierarchical architectures assembled from nanosheet building blocks were successfully synthesized by a hydrothermal method with the assistance of sodium dodecyl benzenesulfonate (SDBS). After calcination, the precursors were easily converted to Y sub(2)(WO sub(4)) sub(3) without an obvious change in morphology. The as-prepared precursors and Y sub(2)(WO sub(4)) sub(3) were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM), and photoluminescence (PL) spectra, respectively. The results reveal that the morphology and dimensions of the as-prepared precursors can be effectively tuned by altering the amounts of organic SDBS and the reaction time, and the possible formation mechanism was also proposed. Upon ultraviolet (UV) excitation, the emission of Y sub(2)(WO sub(4)) sub(3) :xmol% Eu super(3+) microcrystals can be tuned from white to red, and the doping concentration of Eu super(3+) has been optimized. Furthermore, the up-conversion (UC) luminescence properties as well as the emission mechanisms of Y sub(2)(WO sub(4)) sub(3):Yb super(3+)/Ln super(3+) (Ln = Er, Tm, Ho) microcrystals were systematically investigated, which show green (Er super(3+), super(4)S sub(3/2), super(2)H sub(11/2) arrow right super(4)I sub(15/2)), blue (Tm super(3+), super(1)G sub(4) arrow right super(3)H sub(6)) and yellow (Ho super(3+), super(5)S sub(2) arrow right super(5)I sub(8)) luminescence under 980 nm NIR excitation. Moreover, the doping concentration of the Yb super(3+) has been optimized under a fixed concentration of Er super(3+) for the UC emission of Y sub(2)(WO sub(4)) sub(3):Yb super(3+)/Er super(3+).