Highly uniform and monodisperse GdOF:Ln3+ (Ln = Eu, Tb, Tm, Dy, Ho, Sm) microspheres: hydrothermal synthesis and tunable-luminescence properties.
GdOF:Ln(3+) (Ln = Eu, Tb, Tm, Dy, Ho and Sm) microspheres (1.5 μm) with high uniformity and monodispersity have been synthesized via a facile hydrothermal method followed by heat treatment (600 °C). X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), as well as photoluminescence (PL) and cathodoluminescence (CL) spectra are used to characterize the resulting samples. A series of controlled experiments indicate that sodium citrate (Cit(3-)) as a shape modifier introduced into the reaction system plays a critical role in the shape evolution of the final products. Furthermore, the shape and size of the products can be further manipulated by adjusting the dosage of Cit(3-) and pH values in the initial solution. The possible formation mechanism for these microspheres has been presented. Under UV light and low-voltage electron beam excitation, GdOF:Ln(3+) microspheres show the characteristic f-f transitions of Ln(3+) (Eu, Tb/Ho, Tm, Dy and Sm) ions and give bright red, green, blue, yellow and yellowish-orange emission, respectively. In addition, multicolored luminescence containing white emission have been successfully confected for co-doped GdOF:Ln(3+) phosphors by changing the doped Ln(3+) ions and adjusting their doping concentrations due to the simultaneous luminescence of Ln(3+) in the GdOF host, making these materials have potential applications in field-emission display devices.
State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, P. R. China. jlin@ciac.ac.cn.
Yang
Y
Zhang
Xiaojiao
X
Kang
Dongling
D
Geng
Mengmeng
M
Shang
Yuan
Y
Wu
Xuejiao
X
Li
Hongzhou
H
Lian
Ziyong
Z
Cheng
Jun
J
Lin
D002951:Citrates / Q000737:chemistry; D004419:Dysprosium / Q000737:chemistry; D005063:Europium / Q000737:chemistry; D005682:Gadolinium / Q000737:chemistry*; D006695:Holmium / Q000737:chemistry; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008163:Luminescent Measurements; D008863:Microspheres; D012493:Samarium / Q000737:chemistry; D000077559:Sodium Citrate; D013725:Terbium / Q000737:chemistry; D013932:Thulium / Q000737:chemistry; D014466:Ultraviolet Rays
D002951:Citrates; D028581:Lanthanoid Series Elements; D013725:Terbium; D004419:Dysprosium; D000077559:Sodium Citrate; D012493:Samarium; D005063:Europium; D013932:Thulium; D005682:Gadolinium; D006695:Holmium