Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-07T23:04:21.221Z Has data issue: false hasContentIssue false

Evolution of microstructure during the thermal processing of aluminum-modified titania and aluminum/vanadium co-modified titania gels

Published online by Cambridge University Press:  03 March 2011

Francis J. Allison*
Affiliation:
School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
David M. Grant
Affiliation:
School of Mechanical, Materials, and Manufacturing Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
Karen McKinlay
Affiliation:
School of Mechanical, Materials, and Manufacturing Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
Philip G. Harrison
Affiliation:
School of Chemistry, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom
*
a) Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

Sol-gel materials of aluminum-modified TiO2 of nominal composition 5.7 wt% and 10.8 wt% aluminum and aluminum/vanadium co-modified TiO2 of nominal composition 5.7Al–3.5V wt% have been prepared by evaporation of aqueous colloidal sols obtained by the hydrolysis of aqueous solutions of titanium chloride with the appropriate amount of vanadyl oxalate and/or aqueous aluminum nitrate using aqueous ammonia followed by peptization of the resulting hydrated solids using nitric acid. The nature of the sol-gel materials and the behavior upon calcination at temperatures up to 1373 K have been investigated using x-ray fluorescence, x-ray powder diffraction, transmission electron microscopy, and electron diffraction. At 333 K, all the gels comprise small (approximately 5 ± 1 nm) particles of anatase together with traces of brookite and highly crystalline ammonium nitrate. The particle size changes little on thermal treatment at 573 K, but increases significantly at higher temperatures and is accompanied by transformation to rutile. Aluminum-modified gels stabilize the anatase phase from 923 K in unmodified TiO2 to 1023 K in the 6Al/TiO2 gel and 1173 K in the 11Al/TiO2 gel. The alumina in the co-modified gel has a dominating effect on stabilizing the anatase phase until 973 K. Only rutile is present at high temperatures, except for small amounts of phase-separated α-Al2O3 (Corundum). No substitutional incorporation of Al3+ ions in the tetragonal rutile lattice occurs at high temperatures.

Type
Articles
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Allison, F.J., Grant, D.M., McKinlay, K., Bailey, C. and Harrison, P.G.: Evolution of microstructure during the thermal processing of titania and vanadium-modified titania gels. J. Mater Res. 18, 594 (2003).CrossRefGoogle Scholar
2Branemark, P.: Titanium implants. Scandinavian Journal of Plastic Reconstruction Surgery 11, 39 (1977).Google Scholar
3Long, M. and Rack, H.J.: Titanium alloys in total joint replacement—a materials science perspective. Biomaterials 19, 1621 (1998).CrossRefGoogle ScholarPubMed
4Soballe, K. and Overgaard, S.: The current status of hydroxyapatite coating of prostheses. J. Bone Joint Surg. Br. 78B, 689 (1996).Google Scholar
5Degroot, K., Geesink, R., Klein, C. and Serekian, P.: Plasma sprayed coatings of hydroxylapatite. J. Biomed. Mater. Res. 21, 1375 (1987).Google Scholar
6Piveteau, L.D., Gasser, B. and Schlapbach, L.: Evaluating mechanical adhesion of sol-gel titanium dioxide coatings containing calcium phosphate for metal implant application. Biomaterials 21, 2193 (2000).Google Scholar
7Haddow, D.B., Kothari, S., James, P.F., Short, R.D., Hatton, P.V. and vanNoort, R.: Synthetic implant surfaces. 1. The formation and characterization of sol-gel titania films. Biomaterials 17, 501 (1996).Google Scholar
8Li, P.J. and Degroot, K.: Calcium-phosphate formation within sol-gel prepared titania in-vitro and in-vivo. J. Biomed. Mater. Res. 27, 1495 (1993).Google Scholar
9Li, P.J., Kangasniemi, I., Degroot, K. and Kokubo, T.: Bonelike hydroxyapatite induction by a gel-derived titania on a titanium substrate. J. Am. Ceram. Soc. 77, 1307 (1994).CrossRefGoogle Scholar
10Boultif, A. and Louer, D.: J. Appl. Crystallogr . 1,513 (1969).Google Scholar
11 CaRIne-Crystallography-3.0. 1994.Google Scholar
12David, L.Handbook of Chemistry and Physics , 82nd ed. (CRC Press, Boca Raton, 2000).Google Scholar
13 JCPDS No. 08-0452. International Center for Diffraction Data Newton Square, PA, 1981.Google Scholar
14 JCPDS No. 42-1468. International Center for Diffraction Data Newton Square, PA, 1964.Google Scholar
15Cullity, B.D. and Stock, S.: Elements of X-Ray Diffraction (Pearson Higher Education, Essex, U.K., 2001).Google Scholar
16Yang, J., Huang, Y.X. and Ferreira, J.M.F.: Inhibitory effect of alumina additive on the titania phase transformation of a sol-gel-derived powder. J. Mater. Sci. Lett. 16, 1933 (1997).CrossRefGoogle Scholar
17Kumar, S.R., Pillai, S.C., Hareesh, U.S., Mukundan, P. and Warrier, K.G.K.: Synthesis of thermally stable, high surface area anatase- alumina mixed oxides. Mater. Lett. 43, 286 (2000).Google Scholar
18Gutierrez-Alejandre, A., Trombetta, M., Busca, G. and Ramirez, J.: Characterization of alumina-titania mixed oxide supports. 1. TiO2- based supports. Microporous Mater . 12, 79 (1997).CrossRefGoogle Scholar
19Ding, X.Z., Liu, L., Ma, X.M., Qi, Z.Z. and He, Y.Z.: The influence of alumina dopant on the structural transformation of gel-derived nanometer titania powders. J. Mater. Sci. Lett. 13, 462 (1994).Google Scholar
20Yamaguchi, O. and Mukaida, Y.: Formation and transformation of TiO2 (anatase) solid-solution in the system TiO2-Al2O3. J. Am. Ceram. Soc. 72, 330 (1989).Google Scholar
21Reddy, B.M., Ganesh, I. and Chowdhury, B.: Design of stable and reactive vanadium oxide catalysts supported on binary oxides. Cataly. Today 49, 115 (1999).CrossRefGoogle Scholar
22Ding, X.Z., Liu, X.H. and He, Y.Z.: Structural evolution of gel-derived nanocrystalline titania powders doped with ferric oxide. J. Mater. Sci. Lett. 15, 1392 (1996).Google Scholar
23Gribb, A.A. and Banfield, J.F.: Particle size effect on transformation kinetics and phase stability in nanocrystalline TiO2. Am. Mineral 82, 717 (1997).Google Scholar
24Yang, J. and Ferreira, J.M.F.: Inhibitory effect of the Al2O3-SiO2 mixed additives on the anatase-rutile phase transformation. Mater. Lett. 36, 320 (1998).Google Scholar
25Goldstein, A.N., Echer, C.M. and Alivisatos, A.P.: Melting in semiconductor nanocrystals. Science 256, 1425 (1992).Google Scholar
26Reddy, B.M., Chowdhury, B., Reddy, E.P. and Fernandez, A.: X-ray photoelectron spectroscopy study of V2O5 dispersion on a nanosized Al2O3-TiO2 mixed oxide. Langmuir 17, 1132 (2001).Google Scholar
27Saleh, R.Y., Wachs, I.E., Chan, S.S. and Chersich, C.C.: The Interaction of V2O5 With TiO2 (Anatase) - catalyst evolution with calcination temperature and o-xylene oxidation. J. Catal. 98, 102 (1986).CrossRefGoogle Scholar
28 JCPDS No. 21-1276. International Center for Diffraction Data: Newton Square, PA. 1969.Google Scholar