Journal of Materials Science

, Volume 42, Issue 13, pp 4832–4837 | Cite as

The influence of aluminium on the overall properties of SnO2-based varistors

  • Rodrigo ParraEmail author
  • Yves Maniette
  • José A. Varela
  • Miriam S. Castro


The influence of aluminium on the development of the microstructure and on the electrical behaviour of the SnO2 · Co3O4 · Nb2O5 typical varistor system was studied. Two sources of Al were used, alumina (Al2O3) and boehmite (AlO(OH)). The microstructural features were characterised with scanning (SEM) and transmission (TEM) electron microscopies. The different phases present in the studied samples were also studied with XRD, EDS and electron diffraction patterns of selected areas (SAED). Particles containing Sn, Co, Al, and O were unveiled with TEM. Impedance spectroscopy measurements and current density versus electric field characteristics revealed superior electrical properties for samples with AlO(OH). The higher non-linearity (α = 19) was achieved with the addition of 0.1% mol of boehmite. The influence of the secondary phases on the electrical properties is also addressed in this work.


SnO2 Oxygen Vacancy Co3O4 Nb2O5 Unit Cell Volume 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors are grateful to the Programa CYTED (Proyecto PROALERTA), to CONICET (Argentina), to CNPq and FAPESP (Brazil) for the financial support provided for this research. The collaboration of Dr. Alberto Scian at the CETMIC in La Plata is also acknowledged.


  1. 1.
    Gupta TK (1990) J Am Ceram Soc 73:1818CrossRefGoogle Scholar
  2. 2.
    Matsuoka M (1981) In: Levinson LM (ed) Grain boundary phenomena in electronic ceramics. Advances in ceramics, vol 1. The American Ceramic Society Inc., Ohio, pp 290–308Google Scholar
  3. 3.
    Levinson LM, Philipp HM (1996) Am Ceram Soc Bull 85:639Google Scholar
  4. 4.
    Brankovic Z, Brankovic G, Poleti D, Varela JA (2001) Ceram Int 27:115CrossRefGoogle Scholar
  5. 5.
    Kim CH, Kim JH (2004) J Eur Ceram Soc 24:2537CrossRefGoogle Scholar
  6. 6.
    Pianaro SA, Bueno PR, Longo E, Varela JA (1995) J Mater Sci Lett 14:692CrossRefGoogle Scholar
  7. 7.
    Castro MS, Aldao CM (1998) J Eur Ceram Soc 18:2233CrossRefGoogle Scholar
  8. 8.
    Parra R, Varela JA, Aldao CM, Castro MS (2005) Ceram Int 31:737CrossRefGoogle Scholar
  9. 9.
    Brito GES, Pulcinelli SH, Santilli CV, Barelli N (1993) J Mater Sci Lett 12:992CrossRefGoogle Scholar
  10. 10.
    Varela JA, Perazolli LA, Longo E, Leite ER, Cerri JA (1998) Radiat Effect Defect Solid 146:131Google Scholar
  11. 11.
    Parra R, Aldao CM, Varela JA, Castro MS (2005) J Electroceram 14:149CrossRefGoogle Scholar
  12. 12.
    Wang JF, Wang YJ, Su WB, Chen HC, Wang WX (2002) Mater Sci Eng B 96:8CrossRefGoogle Scholar
  13. 13.
    Dhage SR, Ravi V, Date SK (2002) Mater Lett 57:727CrossRefGoogle Scholar
  14. 14.
    Parra R, Castro MS, Varela JA (2004) J Eur Ceram Soc 25:401CrossRefGoogle Scholar
  15. 15.
    Oliveira MM, Soares PC Jr, Bueno PR, Leite ER, Longo E, Varela JA (2003) J Eur Ceram Soc 23:1875CrossRefGoogle Scholar
  16. 16.
    Simoes LPG, Bueno PR, Orlandi MO, Leite ER, Longo E (2003) J Electroceram 10:63CrossRefGoogle Scholar
  17. 17.
    Mendelson MI (1969) J Am Ceram Soc 52:443CrossRefGoogle Scholar
  18. 18.
    Leite ER, Nascimento AM, Bueno PR, Longo E, Varela JA (1999) J Mater Sci Mater El 10:321CrossRefGoogle Scholar
  19. 19.
    Matei Ghimbeu C, van Landschoot RC, Schoonman J, Lumbreras M (in press) J Eur Ceram Soc 27:207Google Scholar
  20. 20.
    Castro MS, Aldao CM (1997) J Eur Ceram Soc 17:1533CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Rodrigo Parra
    • 1
    Email author
  • Yves Maniette
    • 2
  • José A. Varela
    • 2
  • Miriam S. Castro
    • 1
  1. 1.Instituto de Investigaciones en Ciencia y Tecnología de Materiales, (INTEMA, CONICET-UNMdP)Mar del PlataArgentina
  2. 2.Instituto de QuímicaUNESPAraraquaraBrazil

Personalised recommendations