Photoluminescence Studies of ZnO, ZnO:Eu and ZnO:Eu Nanoparticles Covered with Y₂O₃ Matrix

Laishram Robindro Singh

Department of Nanotechnology, North-Eastern Hill University, Shillong, India.

DOI: 10.4236/msa.2015.64032                

Abstract

Development of advanced display and lighting technology such as field emission displays and plasma display panels requires phosphor which has a high efficiency and low degradation. Particle sizes and the locations of dopants in the hosts take an important role in the luminescence emissions of phosphors. ZnO nanoparticles are widely employed in plasma field emission display devices and well investigated; however, lanthanide (Ln³⁺) doped ZnO needs more investigations. In ZnO:Eu the lanthanide ions (Eu3+) may occupy either Zn²⁺ lattice site or on surface of ZnO crystal. The emissions of Eu3+ ion on the surface are the characteristic of Eu₂ O₃ , which leads to weak luminescence emission. To observe such phenomena, nanoparticles of ZnO, 2 at.% Eu3+ doped ZnO (ZnO:Eu) and ZnO:Eu covered with yattria matrix were prepared by wet chemical method at low temperature. The prepared nanoparticles were characterized by XRD and TEM. XRD data reveal the significant phase segregation of the annealed nanoparticles compared with lower heated samples. This phase segregation of Eu3+ ion establishes responsible for the decrease luminescence intensity of annealed ZnO:Eu nanoparticles compared with the as-prepared ZnO:Eu nanoparticles. Improvement on luminescence emissions could be achieved only for the as-prepared ZnO:Eu nanoparticles while covered with yattria matrix.

Keywords

Nanoparticles, Phase Segregation, Dispersion, Luminescence, Core-Shell

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Blasse, G. (1994) Luminescent Materials. Springer, New York. http://dx.doi.org/10.1007/978-3-642-79017-1
[2]	Yen, W.M. and Shionoya, S. (1998) Phosphor Handbook. CRC Press, Boca Raton.
[3]	Hayashi, Y., Narahara, H., Uchida, T., Noguchi, T. and Ibuki, S. (1995) Photoluminescence of Eu-Doped ZnO Phosphors. Japanese Journal of Applied Physics, 34, 1878. http://dx.doi.org/10.1143/JJAP.34.1878
[4]	Mardkovich, V.Z., Hayashi, H., Haemori, M., Fukumura, T. and Kawasaki, M. (2003) Discovery and Optimization of New ZnO-Based Phosphors Using a Combinatorial Method. Advanced Functional Materials, 13, 519-524. http://dx.doi.org/10.1002/adfm.200304335
[5]	Ishizumi, A., Taguchi, Y., Yamamoto, A. and Kanemitsu, Y. (2005) Luminescence Properties of ZnO and Eu3+-Doped ZnO Nanorods. Thin Solid Films, 486, 50-52. http://dx.doi.org/10.1016/j.tsf.2004.11.229
[6]	Yang, C., Cheng, S., Lee, H. and Chen, S. (2006) Effects of Phase Transformation on Photoluminescence Behavior of ZnO:Eu Prepared in Different Solvents. Ceramics International, 32, 37-41. http://dx.doi.org/10.1016/j.ceramint.2004.11.016
[7]	Panatarani, C., Lenggoro, I.W. and Okuyama, K. (2004) The Crystallinity and the Photoluminescent Properties of Spraypyrolized ZnO Phosphor Containing Eu2+ and Eu3+ Ions. Journal of Physics and Chemistry of Solids, 65, 1843- 1847. http://dx.doi.org/10.1016/j.jpcs.2004.06.008
[8]	Singh, L.R., Ningthoujam, R.S., Sudarsan, V., Singh, S.D. and Kulshrestha, S.K. (2008) Probing of Surface Eu3+ Ions Present in ZnO:Eu Nanoparticles by Covering ZnO:Eu Core with Y2O3 Shell: Lu-Minescence Study. Journal of Luminescence, 128, 1544-1550. http://dx.doi.org/10.1016/j.jlumin.2008.02.013
[9]	Singh, L.R., Ningthoujam, R.S., Sudersan, V., Srivastava, I., Singh, S.D., Dey, G.K. and Kulshrestha, S.K. (2008) Luminescence Study on Eu3+ Doped Y2O3 Nanoparticles: Particle Size, Concentration and Core-Shell Formation Effects. Nanotechnology, 19, Article ID: 055201.
[10]	Singh, L.R., Ningthoujam, R.S. and Singh, S.D. (2009) Tuning of Ultra-Violet to Green Emission by Choosing Suitable Excitation Wavelength in ZnO: Quantum Dot, Nanocrystals and Bulk. Journal of Alloys and Compounds, 487, 466-471. http://dx.doi.org/10.1016/j.jallcom.2009.07.166
[11]	JCPDS Card No 41-1105.
[12]	Wang, Z., Lin, C., Liu, X., Li, G., Luo, Y., Quan, Z., Xiang, H. and Lin, J. (2006) Tunable Photoluminescent and Cathodoluminescent Properties of ZnO and ZnO:Zn Phosphors. Journal of Physical Chemistry B, 110, 9469-9476. http://dx.doi.org/10.1021/jp057214t
[13]	Van Dijken, A., Meulenkamp, E.A., Vanmaekelbergh, D. and Meijerink, A. (2000) The Kinetics of the Radiative and Nonradiative Processes in Nanocrystalline ZnO Particles upon Photoexcitation. Journal of Physical Chemistry B, 104, 1715-1723. http://dx.doi.org/10.1021/jp993327z
[14]	Jia, W., Monge, K. and Fernandez, F. (2003) Energy Transfer from the Host to Eu3+ in ZnO. Optical Materials, 23, 27- 32. http://dx.doi.org/10.1016/S0925-3467(03)00054-5
[15]	Bendre, B.S. and Mahamuni, S. (2004) Luminescence in ZnO Quantum Particles. Journal of Materials Research, 19, 737-740. http://dx.doi.org/10.1557/jmr.2004.19.3.737
[16]	Ntwaeabirwam, O.M. and Holloway, P.H. (2005) Enhanced Photoluminescence of Ce3+ Induced by an Energy Transfer from ZnO Nanoparticles Encapsulated in SiO2. Nanotechnology, 16, 865-872. http://dx.doi.org/10.1088/0957-4484/16/6/042
[17]	Li, D., Leung, Y.H., Djurisic, A.B., Liu, Z.T., Xie, M.H., Shi, S.L., Xu, S.J. and Chan, W.K. (2004) Different Origins of Visible Luminescence in ZnO Nanostructures Fabricated by the Chemical and Evaporation Methods. Applied Physics Letters, 85, 1601-1604.
[18]	Kamat, P.V. and Patrick, B. (1992) Photophysics and Photochemistry of Quantized Zinc Oxide Colloids. Journal of Physical Chemistry, 96, 6829-6834. http://dx.doi.org/10.1021/j100195a055
[19]	Vanheusden, K., Warren, W., Seager, C.H., Tallant, D.R., Voigt, J.A. and Gnade, B.E. (1996) Mechanisms behind Green Photoluminescence in ZnO Phosphor Powders. Journal of Applied Physics, 79, 7983-7991. http://dx.doi.org/10.1063/1.362349
[20]	Halliburton, L.E., Giles, N.C., Graces, N.Y., Luo, M., Xu, C., Bai, L. and Boatner, L.A. (2005) Production of Native Donors in ZnO by Annealing at High Temperature in Zn Vapor. Applied Physics Letters, 87, 172108-172111. http://dx.doi.org/10.1063/1.2117630
[21]	Djurisic, A.B., Leung, Y.H., Choy, W.C.H., Cheah, K.W. and Chan, W.K. (2004) Visible Photoluminescence in ZnO Tetrapod and Multipod Structures. Applied Physics Letters, 84, 2635-2638. http://dx.doi.org/10.1063/1.1695633
[22]	Graces, N.Y., Wang, L., Bai, L., Giles, N.C., Halliburton, L.E. and Cantwell, G. (2002) Role of Copper in the Green Luminescence Crystals. Applied Physics Letters, 81, 622-625. http://dx.doi.org/10.1063/1.1494125
[23]	Fonoberov, V.A., Alim, K.A., Balandin, A.A., Xiu, F. and Liu, J. (2006) Photoluminescence Investigation of the Carrier Recombination Processes in ZnO Quantum Dots and Nanocrystals. Physical Review B, 73, 165317-165326. http://dx.doi.org/10.1103/PhysRevB.73.165317
[24]	Lima, S.A.M., Sigdi, F.A. and Davolos, M.R. (2003) Pechini’s Solution as Precursor for Eu(III)-Containing ZnO Films. Journal of Solid State Chemistry, 171, 287-290. http://dx.doi.org/10.1016/S0022-4596(02)00178-0
[25]	Nageno, Y., Takebe, H., Morinaga, K. and Izumitani, T. (1994) Effect of Modifier Ions on Fluorescence and Absorption of Eu3+ in Alkali and Alkaline Earth Silicate Glasses. Journal of Non-Crystalline Solids, 169, 288-294. http://dx.doi.org/10.1016/0022-3093(94)90324-7
[26]	Merino, R.P., Gallardo, A.C., Rocha, M.G., Calderon, I.H., Castano, V. and Rodriguez, R. (2001) Photoluminescence of TiO2: Eu3+ Thin Films Obtained by Sol-Gel on Si and Corning Glass Substrates. Thin Solid Films, 401, 118-123. http://dx.doi.org/10.1016/S0040-6090(01)01608-X
[27]	Vetrone, F., Boyer, J.C. and Capobianco, J.A. (2004) Yttrium Oxide Nanocrystals: Luminescent Properties and Appli- cations. In: Nalwa, H.S., Ed., Encyclopedia of Nanoscience and Nanotechnology, Vol. 10, 725-765.