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Flame-coating of titania particles with silica

Published online by Cambridge University Press:  03 March 2011

A. Teleki ,
S.E. Pratsinis ,
K. Wegner ,
R. Jossen  and
F. Krumeich
A. Teleki
Affiliation:
Particle Technology Laboratory, Institute of Process Engineering, Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology Zurich (ETHZ), CH-8092 Zurich, Switzerland
S.E. Pratsinis*
Affiliation:
Particle Technology Laboratory, Institute of Process Engineering, Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology Zurich (ETHZ), CH-8092 Zurich, Switzerland
K. Wegner
Affiliation:
Particle Technology Laboratory, Institute of Process Engineering, Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology Zurich (ETHZ), CH-8092 Zurich, Switzerland
R. Jossen
Affiliation:
Particle Technology Laboratory, Institute of Process Engineering, Department of Mechanical and Process Engineering, Swiss Federal Institute of Technology Zurich (ETHZ), CH-8092 Zurich, Switzerland
F. Krumeich
Affiliation:
Laboratory of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology Zurich (ETHZ), CH-8093 Zurich, Switzerland
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

Silica/titania composite particles were prepared by co-oxidation of titanium-tetra-isopropoxide and hexamethyldisiloxane in a co-flow diffusion flame reactor. The influence of precursor composition on product powder characteristics was studied by x-ray diffraction, nitrogen adsorption, electron microscopy, elemental mapping, and energy-dispersive x-ray analysis. The flame temperature was measured by Fourier transform infrared spectroscopy. The evolution of composite particle morphology from ramified agglomerates to spot- or fully coated particles was investigated by thermophoretic sampling and transmission/scanning electron microscopy. At 40–60 wt% TiO2, particles with segregated regions of silica and titania were formed, while at 80 wt% TiO2 rough silica coatings were obtained. Rapid flame-quenching with a critical flow nozzle at 5 cm above the burner nearly halved the product particle size, changed its crystallinity from pure anatase to mostly rutile and resulted in smooth silica coatings on particles containing 80 wt% TiO2.

Keywords

CompositeFlame synthesisNanoparticle
Type
Articles
Information
Journal of Materials Research , Volume 20 , Issue 5 , May 2005 , pp. 1336 - 1347
Copyright
Copyright © Materials Research Society 2005

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References

REFERENCES

1.Ulrich, G.D.: Flame synthesis of fine particles. Chem. Eng. News 62, 22 (1984).CrossRefGoogle Scholar
2.Braun, J.H.: Titanium dioxide—A review. J. Coat. Technol. 69, 59 (1997).Google Scholar
3.Nussbaumer, R.J., Caseri, W.R., Smith, P. and Tervoort, T.: Polymer-TiO2 nanocomposites: A route towards visually transparent broadband UV filters and high refractive index materials. Macromol. Mater. Eng. 288, 44 (2003).CrossRefGoogle Scholar
4.Lademann, J., Weigmann, H.J., Schafer, H., Muller, G. and Sterry, W.: Investigation of the stability of coated titanium microparticles used in sunscreens. Skin Pharmacol. Appl. Skin Physiol. 13, 258 (2000).CrossRefGoogle ScholarPubMed
5.Winkler, J.: Nano-scaled titanium dioxide—properties and use in coatings with special functionality. Macromol. Symp. 187, 317 (2002).3.0.CO;2-H>CrossRefGoogle Scholar
6.Gesenhues, U.: Contribution of TiO2 to the durability and the degradation of organic coatings. Double Liaison 43, 32 (1996).Google Scholar
7.Picatonotto, T., Vione, D. and Carlotti, M.E.: Effect of some additives used in the cosmetic field on the photocatalytic activity of rutile. J. Dispersion Sci. Technol. 23, 845 (2002).CrossRefGoogle Scholar
8.Iler, R.K.: Product comprising a skin of dense, hydrated amorphous silica bound upon a core of another solid material and process of making same. U.S. Patent No. 2 885 366 (1959).Google Scholar
9.Werner, A.J.: Titanium dioxide pigment coated with silica and alumina. U.S. Patent No. 3 437 502 (1969).Google Scholar
10.Kinniard, S.P. and Campeotto, A.: Method for manufacturing high opacity, durable pigments. U.S. Patent No. 6 528 568 B2 (2003).Google Scholar
11.Herkimer, S.M.: Process for manufacturing titanium dioxide pigment having a hydrous oxide coating using a media mill. U.S. Patent No. 5 730 795 (1998).Google Scholar
12.Egerton, T.A.: The modification of fine powders by inorganic coatings. KONA 16, 46 (1998).CrossRefGoogle Scholar
13.Piccolo, L., Calcagno, B., and Bossi, E.: Process for the post-treatment of titanium dioxide pigments. U.S. Patent No. 4 050 951 (1977).Google Scholar
14.Santacesaria, E., Carra, S., Pace, R.C. and Scotti, C.: Vapor-phase treatment of titanium-dioxide with metal chlorides 1. The reactions of coating performed by Al2Cl6, SiCl4, and ZrCl4 in the vapor-phase. Ind. Eng. Chem. Prod. Res. Dev. 21, 496 (1982).CrossRefGoogle Scholar
15.Akhtar, M.K., Pratsinis, S.E. and Mastrangelo, S.V.R.: Dopants in vapor-phase synthesis of titania powders. J. Am. Ceram. Soc. 75, 3408 (1992).Google Scholar
16.Hung, C.H. and Katz, J.L.: Formation of mixed-oxide powders in flames 1. TiO2–SiO2. J. Mater. Res. 7, 1861 (1992).Google Scholar
17.Vemury, S. and Pratsinis, S.E.: Dopants in flame synthesis of titania. J. Am. Ceram. Soc. 78, 2984 (1995).CrossRefGoogle Scholar
18.Kodas, T.T., Powell, Q.H., and And, B.erson: Coating of TiO2 pigment by gas-phase and surface reactions. International Patent No. WO 96/36441 (1996).Google Scholar
19.Powell, Q.H., Fotou, G.P., Kodas, T.T., Anderson, B.M. and Guo, Y.X.: Gas-phase coating of TiO2 with SiO2 in a continuous flow hot-wall aerosol reactor. J. Mater. Res. 12, 552 (1997).CrossRefGoogle Scholar
20.Ehrman, S.H., Friedlander, S.K. and Zachariah, M.R.: Characteristics of SiO2/TiO2 nanocomposite particles formed in a premixed flat flame. J. Aerosol Sci. 29, 687 (1998).CrossRefGoogle Scholar
21.Ehrman, S.H., Friedlander, S.K. and Zachariah, M.R.: Phase segregation in binary SiO2/TiO2 and SiO2/Fe2O3 nanoparticle aerosols formed in a premixed flame. J. Mater. Res. 14, 4551 (1999).CrossRefGoogle Scholar
22.Lee, S.K., Chung, K.W. and Kim, S.G.: Preparation of various composite TiO2/SiO2 ultrafine particles by vapor-phase hydrolysis. Aerosol Sci. Technol. 36, 763 (2002).Google Scholar
23.Stark, W.J. and Pratsinis, S.E.: Aerosol flame reactors for manufacture of nanoparticles. Powder Technol. 126, 103 (2002).CrossRefGoogle Scholar
24.Wegner, K., Stark, W.J. and Pratsinis, S.E.: Flame-nozzle synthesis of nanoparticles with closely controlled size, morphology and crystallinity. Mater. Lett. 55, 318 (2002).Google Scholar
25.Wegner, K. and Pratsinis, S.E.: Nozzle-quenching process for controlled flame synthesis of titania nanoparticles. AIChE J. 49, 1667 (2003).Google Scholar
26.Kammler, H.K., Pratsinis, S.E., Morrison, P.W. and Hemmerling, B.: Flame temperature measurements during electrically assisted aerosol synthesis of nanoparticles. Combust. Flame 128, 369 (2002).CrossRefGoogle Scholar
27.Kammler, H.K., Jossen, R., Morrison, P.W., Pratsinis, S.E. and Beaucage, G.: The effect of external electric fields during flame synthesis of titania. Powder Technol. 135, 310 (2003).CrossRefGoogle Scholar
28.Cheary, R.W. and Coelho, A.: A fundamental parameter approach to x-ray line-profile fitting. J. Appl. Crystallogr. 25, 109 (1992).Google Scholar
29.Daubert, T.E., Danner, R.P., Sibul, H.M. and Stebbins, C.C.: Physical and Thermodynamic Properties of Pure Chemicals: Data Compilation, Design Institute for Physical Property Data, American Institute of Chemical Engineers; NSRDS, National Standard Reference Data System (Taylor & Francis, New York, NY, 1997).Google Scholar
30.Mueller, R., Kammler, H.K., Pratsinis, S.E., Vital, A., Beaucage, G. and Burtscher, P.: Non-agglomerated dry silica nanoparticles. Powder Technol. 140, 40 (2004).Google Scholar
31.Ahn, K.H., Park, Y.B. and Park, D.W.: Kinetic and mechanistic study on the chemical vapor deposition of titanium dioxide thin films by in situ FTIR using TTIP. Surf. Coat. Technol. 171, 198 (2003).Google Scholar
32.Morrison, P.W., Raghavan, R., Timpone, A.J., Artelt, C.P. and Pratsinis, S.E.: In situ Fourier transform infrared characterization of the effect of electrical fields on the flame synthesis of TiO2 particles. Chem. Mater. 9, 2702 (1997).Google Scholar
33.Stakheev, A.Y., Shpiro, E.S. and Apijok, J.: XPS and XAES Study of TiO2-SiO2 mixed-oxide system. J. Phys. Chem. 97, 5668 (1993).Google Scholar
34.Anpo, M., Shima, T., Kodama, S. and Kubokawa, Y.: Photocatalytic hydrogenation of CH3CCH with H2O on small-particle TiO2–Size quantization effects and reaction intermediates. J. Phys. Chem. 91, 4305 (1987).Google Scholar
35.Lassaletta, G., Fernandez, A., Espinos, J.P. and González-Elipe, A.R.: Spectroscopic characterization of quantum-sized TiO2 supported on silica: Influence of size and TiO2–SiO2 interface composition. J. Phys. Chem. 99, 1484 (1995).Google Scholar
36.DeVries, R.C., Roy, R. and Osborn, E.F.: The system TiO2–SiO2. Trans. Brit. Ceram. Soc. 53, 525 (1954).Google Scholar
37.Schultz, P.C.: Binary titania-silica glasses containing 10 to 20 wt% TiO2. J. Am. Ceram. Soc. 59, 214 (1976).Google Scholar
38.Nakaso, K., Okuyama, K., Shimada, M. and Pratsinis, S.E.: Effect of reaction temperature on CVD-made TiO2 primary particle diameter. Chem. Eng. Sci. 58, 3327 (2003).CrossRefGoogle Scholar
39.Xiong, Y. and Pratsinis, S.E.: Formation of agglomerate particles by coagulation and sintering 1. A 2-dimensional solution of the population balance equation. J. Aerosol Sci. 24, 283 (1993).Google Scholar
40.Powell, Q.H., Fotou, G.P., Kodas, T.T. and Anderson, B.M.: Synthesis of alumina- and alumina/silica-coated titania particles in an aerosol flow reactor. Chem. Mater. 9, 685 (1997).Google Scholar
41.Xiong, Y., Akhtar, M.K. and Pratsinis, S.E.: Formation of agglomerate particles by coagulation and sintering 2. The evolution of the morphology of aerosol-made titania, silica and silica-doped titania powders. J. Aerosol Sci. 24, 301 (1993).Google Scholar