Articles
All articles | Recent articles
Photocatalytic Properties of Nanocrystalline TiO2 coupled with Up-Conversion Phosphors
S. Mavengere, H. M. Yadav, J.-S. Kim
Department of Materials Science and Engineering, University of Seoul, Seoul 02504, Republic of Korea
received October 28, 2016, received in revised form December 9, 2016, accepted January 10, 2017
Vol. 8, No. 1, Pages 67-72 DOI: 10.4416/JCST2016-00089
Abstract
NaYF4:(Yb3+, Er3+) up-conversion phosphor was synthesized with the combustion method and coated with TiO2 nanoparticles by means of a sol-gel technique. Emission peaks of the up-conversion phosphor were located at 523, 544 and 655 nm under irradiation with a 980 nm infrared (IR) dot laser light with 40 mW. TiO2-coated NaYF4:(Yb3+, Er3+) phosphor showed similar emission peaks with reduced intensities. The photocatalytic activity of the TiO2-coated up-conversion phosphor particles was investigated based on the degradation of aqueous methylene blue (MB) solution under irradiation with a 200-W visible light of wavelength λ > 410 nm. TiO2-coated NaYF4:(Yb3+, Er3+) phosphor particles showed enhanced photocatalytic activity compared with pure TiO2 powders. The mechanism for enhanced photocatalytic activity was explained in relation to the energy band structure that exists at the interlayer between the NaYF4:(Yb3+, Er3+) phosphor and TiO2 nanoparticles.
Download Full Article (PDF)
Keywords
Up-conversion phosphor, NaYF4:(Yb3+, Er3+), TiO2,photocatalysis, visible-light photo-reaction
References
1 Yadav, H.M., Kolekar, T.V, Pawar, S.H., Kim, J.-S.: Enhanced photocatalytic inactivation of bacteria on Fe-containing TiO2 nanoparticles under fluorescent light, J. Mater. Sci. Mater. Med., 27, 57, (2016).
2 Yadav, H.M. et al.: Enhanced visible light photocatalytic activity of Cr3+-doped anatase TiO2 nanoparticles synthesized by sol-gel method, J. Mater. Sci. Mater. Electron., 27, 526 – 534, (2015).
3 Lin, W., Cheng, H., Ming, J., Yu, Y., Zhao, F.: Deactivation of Ni/TiO2 catalyst in the hydrogenation of nitrobenzene in water and improvement in its stability by coating a layer of hydrophobic carbon, J. Catal., 291, 149 – 154, (2012).
4 Lafond, V., Mutin, P.H., Vioux, A.: Non-hydrolytic sol-gel routes based on alkyl halide elimination: toward better mixed oxide catalysts and new supports application to the preparation of a SiO2-TiO2 epoxidation catalyst, J. Mol. Catal. A: Chem., 182 – 183, 81 – 88, (2002).
5 Pan, J.H., Sun, D.D., Lee, W.I.: Preparation of periodically organized mesoporous bicomponent TiO2 and SnO2-based thin films by controlling the hydrolytic kinetics of inorganic precursors during EISA process, Mater. Lett., 65, 2836 – 2840, (2011).
6 Kim, J.S., Sung, H.J., Kim, B.J.: Photocatalytic characteristics for the nanocrystalline TiO2 on the Ag-doped CaAl2O4:(Eu,Nd) phosphor, Appl. Surf. Sci., 334, 151 – 156, (2015).
7 Kim, J.-S., Kim, S.-W., Jung, S.-C.: Photocatalytic reaction characteristics of the titanium dioxide supported on the long phosphorescent phosphor by a low pressure chemical vapor deposition, J. Nanosci. Nanotechnol., 14, 7751 – 7755, (2014).
8 Chen, D. et al.: Dopant-induced phase transition: A new strategy of synthesizing hexagonal upconversion NaYF4 at low temperature, Chem. Commun. (Camb)., 47, 5801 – 5803, (2011).
9 Tamrakar, R.K., Bisen, D.P., Upadhyay, K., Sahu, I.P.: Upconversion and colour tunability of Gd2O3:Er3+ phosphor prepared by combustion synthesis method, J. Alloy. Compd., 655, 423 – 432, (2016).
10 Gonell, F. et al.: Photon up-conversion with lanthanide doped oxide particles for solar H2 generation, J. Phys. Chem. C, 118, 140505212111008, (2014).
11 Liu, Y. et al.: Coupling effects of Au-decorated core-shell β-NaYF4:Er/Yb@SiO2 microprisms in dye-sensitized solar cells: plasmon resonance versus upconversion, Electrochim. Acta, 180, 394 – 400, (2015).
12 Bednarkiewicz, A., Wawrzynczyk, D., Nyk, M., Samoć, M.: Tuning red-green-white up-conversion color in nano NaYF4:Er/Yb phosphor, J. Rare Earth., 29, 1152 – 1156, (2011).
13 Sauvet, A.-L., Baliteau, S., Lopez, C., Fabry, P.: Synthesis and characterization of sodium titanates Na2Ti3O7 and Na2Ti6O13, J. Solid State Chem., 177, 4508 – 4515, (2004).
14 Bavykin, D.V., Walsh, F.C.: Kinetics of alkali metal ion exchange into nanotubular and nanofibrous titanates, J. Phys. Chem. C, 111, 14644 – 14651, (2007).
15 Yoon, J.-H., Kim, J.-S.: Investigation of photocatalytic reaction for the titanium dioxide-phosphor composite, Ionics (Kiel), 16, 131 – 135, (2010).
Copyright
Göller Verlag GmbH
