Abstract
In this study, a three-stage process consisting of mechanical milling, heat treatment, and washing has been used to manufacture nanoparticulate ZnO powders with a controlled particle size and minimal agglomeration. By varying the temperature of the post-milling heat treatment, it was possible to control the average particle size over the range of 28–57 nm. The photocatalytic activity of these powders was characterized by measuring the hydroxyl radical concentration as a function of irradiation time using the spin-trapping technique with electron paramagnetic resonance spectroscopy. It was found that there exists an optimum particle size of approximately 33 nm for which the photocatalytic activity is maximized. The existence of this optimal particle size is attributable to an increase in the charge carrier recombination rate, which counteracts the increased activity arising from the higher specific surface area for a sufficiently small particle size.
Similar content being viewed by others
References
Almquist C.B. and Biswas P. (2002). Role of synthesis method and particle size of nanostructured TiO2 on its photoactivity. J. Catal. 212: 145
Cullity B., 1978. Elements of X-Ray Diffraction. 2nd edn. Addison-Wesley, Reading
Dodd A.C. and McCormick P.G. (2001). Solid state chemical synthesis of nanoparticulate zirconia. Acta Mater. 49: 4215
Dodd A.C. and McCormick P.G. (2003). Factors Affecting the particle size of powders synthesised by mechanochemical processing. J. Metast. Nanocryst. Mater. 15–16: 545
Grela M.A., Coronel M.E.J. and Colussi A.J. (1996). Quantitative spin-trapping studies of weakly illuminated titanium dioxide sols. implications of the mechanism of photocatalysis. J. Phys. Chem. 100: 16940
Hoffmann M., Martin S., Choi W. and Bahnemann D. (1995). Environmental applications of semiconductor photocatalysis. Chem. Revs. 95: 69–95
Innes B., Tsuzuki T., Dawkins H., Dunlop J., Trotter G., Nearn M. and McCormick P. (2002). Nanotechnology and the cosmetic chemist. NutraCos. 1: 7–12
Jaeger C.D. and Bard A.J. (1979). Spin trapping and electron spin resonance detection of radical intermediates in the photodecomposition of water at TiO2 particulate systems. J. Phys. Chem. 83: 3146
Janzen E.G. (1971). Spin trapping. Acc. Chem. Res. 4: 31–40
Kerker M. (1969). The scattering of light. Academic Press, New York
McCormick P.G., Tsuzuki T., Robinson J. and Ding J. (2001). Nanopowders synthesized by mechanochemical processing. Adv. Mat. 13: 1008
Pearton S., Norton D., Ipa K., Heo Y. and Steiner T. (2003). Recent progress in processing and properties of ZnO. Superlattices Microstruct. 34: 3–32
Tsuzuki T. and McCormick P.G. (2001). Synthesis of ultrafine ceria powders by mechanochemical processing. J. Am. Ceram. Soc. 84: 1453
Tsuzuki T. and McCormick P.G. (1997). Synthesis of CdS quantum dots by mechanochemical reaction. Appl. Phys. A. 65: 607
Wang C.-C., Zhang Z. and Ying J. (1997). Photocatalytic decomposition of halogenated organics over nanocrystalline titania. Nanostruct. Mat. 9: 583
Zhang Z., Wang C.-C., Zakaria R. and Ying J.Y. (1998). Role of particle size in nanocrystalline TiO2-based photocatalysts. J. Phys. Chem. B. 102: 10871
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Dodd, A.C., McKinley, A.J., Saunders, M. et al. Effect of Particle Size on the Photocatalytic Activity of Nanoparticulate Zinc Oxide. J Nanopart Res 8, 43–51 (2006). https://doi.org/10.1007/s11051-005-5131-z
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11051-005-5131-z