Enhanced UV emission of Y-doped ZnO nanoparticles
Highlights
► Rare earth element Y was doped in ZnO nanoparticles and the saturation concentration of Y in ZnO lattice is 6.12 at%. ► The UV emission of ZnO can be significantly increased by Y doping in ZnO lattice. ► The deep level emission of ZnO was suppressed by Y doping and a high intensity ratio (32) of UV to DLE was obtained.
Introduction
Rare-earth (RE) doped semiconductors have been the focus of numerous investigations because of their unique optical properties and promising applications in optoelectronic devices [1], [2], [3], [4], [5]. As one of the most important II–VI semiconductors with wide band gap, ZnO is an environmentally friendly and chemically stable material and is a suitable host material for the doping of metal and RE ions because of its outstanding photoluminescence (PL) properties [6], [7], [8]. RE-doped ZnO nanocrystals are expected to be potential candidate materials for flat panel displays due to enhanced emission in visible light range [9], [10], [11]. Ce-doped ZnO [12] showed red shift and Er-doped ZnO thin films [13] showed blue shift in their photoluminescence spectra. The UV luminescence of ZnO was quenched by Eu-doping and a strong visible emission around 618 nm was observed [14].
It is well known that UV emission in photoluminescence is the main character of ZnO and an intensive UV emission is desirable. However, until now, few experimental studies have focused on the enhance intensity of UV by doping RE or metallic ions into ZnO lattice. In this paper, Y-doped ZnO nanoparticles were prepared via sol–gel method and the effect of Y concentration on the photoluminescence properties was investigated.
Section snippets
Experimental
Zn1−xYxO powders with x = 0.00, 0.03, 0.05, 0.07 and 0.09 at% were prepared via sol–gel method. All the chemical reagents used in the experiment were analytical grade purity. Zinc nitrate [Zn(NO3)2·6H2O] at 0.1 M concentration and different ratios of yttrium nitrate at 0.1 M [Y(NO3)2·3H2O] were dissolved into 0.3 M citrate acid [C6H8O7·H2O] solution with stirring to form sol. Then, the mixture was polymerized to form gel at 80 °C for 12 h. The swelled gel was pyrolyzed at 130 °C for 5 h to obtain the
Results and discussion
Fig. 1 shows the XRD patterns of the as-synthesized Zn1−xYxO (x = 0.00, 0.01, 0.03, 0.05, 0.07) and x = 0.09 inset in it. For Zn1−xYxO (0.00 ≤ x ≤ 0.07), all the diffraction peaks can be indexed to a wurtzite structure of ZnO which belongs to space group (P63mc). No diffraction peaks from any other chemical species such as yttrium oxides were detected within the sensitivity of XRD. For Zn1−xYxO with x = 0.09, a peak near the peak of Zn1−xYxO (1 0 0) plane emerges, as shown in the insert in Fig. 1. As
Conclusions
- 1.
Y-doped ZnO nanopaticals with particle size of about 40–60 nm were synthesized by the sol–gel method and Y ions were successfully incorporated into ZnO lattice, testified by XRD and XPS spectra.
- 2.
Doping of Y element into the ZnO lattice induces the increase of lattice constant and the broadening of diffraction peak. By analyzing the XRD pattern, the saturation doping concentration of Y in ZnO lattice is estimated to be about 6.12 at%, above this concentration, Y2O3 phase forms in the powder sample.
- 3.
Acknowledgments
This work was supported by National Nature Science Foundation (Grant no. 50871046), the Foundation of National Key Basic Research and Development Program (no. 2010CB631001) and the Applications of Environmental Friendly Materials from the Key Laboratory Ministry of Education, Jilin normal University.
References (26)
- et al.
Applied Physics Letters
(2005) - et al.
Journal of Physical Chemistry C
(2007) - et al.
Nano Letters
(2005) - et al.
Chemistry of Materials
(2003) - et al.
Journal of Physical Chemistry B
(2005) - et al.
Advanced Materials
(2006) - et al.
Journal of Applied Physics
(2006) - et al.
Optical Materials
(2006) - et al.
Journal of Applied Physics
(2010) - et al.
Journal of Physical Chemistry C
(2008)
Journal of Alloys and Compounds
Journal of Applied Physics
Physica E
Cited by (84)
Defects passivity and UV emission characteristics in yttrium doped ZnO nanoparticles
2024, Inorganic Chemistry CommunicationsA multiferroic coupling mechanism in the polar interface region of GaN-ZnO heterojunction: A first-principle study
2024, Journal of Magnetism and Magnetic MaterialsSynthesis of yttrium doped zinc oxide nanorods for display, forensic and supercapacitor applications
2023, Inorganic Chemistry Communications