Reduced Activation Energy of Iron and Copper Ion Doped Mullite which Can Be Used as a
Substrate in Electronic Industry
Copyright © 2013 SciRes. JSEMAT
16
5. Conclusion
Fe2+ and Cu2+ doped mullite composites have been syn-
thesized by the sol-gel technique, their phase evolution;
band gap activation energy has been investigated. The
results showed that with increase in Fe2+ and Cu2+ ion
concentration the crystallization of mullite was enhanced,
which is evident from X-ray diffraction and FESEM of
the composites. The activation energy of resistivity/band
gap energy, Eg, attains a minimum value 1.11 eV at 0.04
M concentration for Cu2+ ion. It has been observed that
the resistivity as well as the band gap energy corresponds
to semiconductors and due to the low activation energy it
can be used as a substrate in the electronic industry.
6. Acknowledgements
We are grateful to the members of the, Department of
Science and Technology and University Grant Commis-
sion (PURSE program), Government of India, for their
assistance.
REFERENCES
[1] I. A. Aksay, D. M. Dabbs and M. Sarikaya, “Mullite for
Structural, Electronic, and Optical Applications,” Journal
of the American Ceramic Society, Vol. 74, No. 10, 1991,
pp. 2343-2358. doi:10.1111/j.1151-2916.1991.tb06768.x
[2] H. Schneider, “Kinetics of Crack Tip Blunting of
Glasses,” Journal of the American Ceramic Society, Vol.
70, No. 1, 1987, pp. 43-48.
doi:10.1111/j.1151-2916.1987.tb04851.x
[3] J. Schreuer, B. Hildmann and H. Schneider, “Elastic
Properties of Mullite Single Crystals up to 1400˚C,”
Journal of the American Ceramic Society, Vol. 89, No. 5,
2006, pp. 1624-1631.
doi:10.1111/j.1551-2916.2006.00921.x
[4] H. Schneider, J. Schreuer and B. Hildmann, “Structure
and Properties of Mullite—A Review,” Journal of the
European Ceramic Society, Vol. 28, No. 2, 2008, pp.
329-344. doi:10.1016/j.jeurceramsoc.2007.03.017
[5] D. S. Perera and G. Allott, “Mullite Morphology in Fired
Kaolinite/Halloysite Clays,” Journal of Materials Science
Letters, Vol. 4, No. 10, 1985, pp. 1270-1372.
doi:10.1007/BF00723478
[6] S. Rahman and S. Freimann, “The Real Structure of Mul-
lite,” In: H. Schneider and S. Komarneni, Eds., Mullite,
Wiley-VCH, Weinheim, 2005.
[7] M. Schmucker and H. Schneider, “Mullite-Type Gels and
Glasses,” In: Schneider and S. Komarneni, Eds., Mullite,
Wiley-VCH, Weinheim, 2005.
[8] V. V. Vol’khin, I. L. Kazakova, P. Pongratz and E. Hal-
wax, “Mullite Formation from Highly Homogeneous
Mixtures of Al2O3 and SiO2,” Inorganic Materials, Vol.
36, No. 4, 2000, pp. 375-379. doi:10.1007/BF02758084
[9] Y. F. Chen, M. C. Wang and M. H. Hon, “Phase Trans-
formation and Growth of Mullite in Kaolin Ceramics,”
Journal of the European Ceramic Society, Vol. 24, No. 8,
2004, pp. 2389-2397.
doi:10.1016/S0955-2219(03)00631-9
[10] F. Sahnoune, M. Chegaar, N. Saheb, P. Goeuriot and F.
Valdivieso, “Algerian Kaolinite Used for Mullite Forma-
tion,” Applied Clay Science, Vol. 38, No. 3-4, 2008, pp.
304-310. doi:10.1016/j.clay.2007.04.013
[11] J. Pascual and J. Zapatero, “Preparation of Mullite
Ceramics from Coprecipitated Aluminum Hydroxide and
Kaolinite Using Hexamethylenediamine,” Journal of the
American Ceramic Society, Vol. 83, No. 11, 2000, pp.
2677-2680. doi:10.1111/j.1151-2916.2000.tb01614.x
[12] Y. F. Tang ,Z. D. Ling ,Y. N. Lu ,A. D. Li, H. Q. Ling ,Y.
J. Wang and Y. Shao, “Study on the Densification of
Composite Coating Particles of α-Al2O3-SiO2,” Materials
Chemistry and Physics, Vol. 75, No. 1-3, 2002, pp. 265-
269. doi:10.1016/S0254-0584(02)00074-3
[13] V. Viswabaskaran, F. D. Gnanama and M. Balasubrama-
nian, “Mullitisation Behaviour of South Indian Clays,”
Ceramics International, Vol. 28, No. 5, 2002, pp. 557-
564. doi:10.1016/S0272-8842(02)00010-X
[14] V. Viswabaskaran, F. D. Gnanama and M. Balasubrama-
nian, “Mullitisation Behaviour of Calcined Clay-Alumina
Mixtures,” Ceramics International, Vol. 29, No. 5, 2003,
pp. 561-571. doi:10.1016/S0272-8842(02)00203-1
[15] V. Viswabaskaran, F. D. Gnanama and M. Balasubrama-
nian, “Mullite from Clay-Reactive Alumina for Insulating
Substrate Application,” Applied Clay Science, Vol. 25,
No. 1-2, 2004, pp. 29-35. doi:10.1016/j.clay.2003.08.001
[16] D. Roy, B. Bagchi, S. Das and P. Nandy, “Electrical and
Dielectric Properties of Sol-Gel Derived Mullite Doped
with Transition Metals,” Materials Chemistry and Phys-
ics, Vol. 138, No. 1, 2013, pp. 375-383.
doi:10.1016/j.matchemphys.2012.11.070
[17] T. Martisius and R. Giraitis, “Influence of Copper Oxide
on Mullite Formation from Kaolinite,” Journal of Mate-
rials Chemistry, Vol. 13, No. 1, 2002, pp. 121-124.
doi:10.1039/b206711k
[18] R. S. Aza, S. J. Moya, T. Epicier and G. Fantozzi, “Im-
proved High-Temperature Mechanical Properties of Zir-
conia-Doped Mullite,” Journal of Materials Science Let-
ters , Vol. 9, No. 12, 1990, pp. 1400-1402.
doi:10.1007/BF00721596
[19] R. Torecillas Imose, Y. Takano, M. Yoshinaka and K. O.
Hirota Yamaguchi, “Novel Synthesis of Mullite Powder
with High Surface Area,” Journal of the American Ce-
ramic Society, Vol. 81, No. 6, 1998, pp. 1537-1540.
doi:10.1111/j.1151-2916.1998.tb02513.x
[20] B. L. Kong, T. S. Zhang, J. Ma and F. Boey, “Some Main
Group Oxides on Mullite Phase Formation and Micro-
structure Evolution,” Journal of Alloys and Compounds,
Vol. 359, No. 1-2, 2003, pp. 292-299.
doi:10.1016/S0925-8388(03)00193-2
[21] B. Bagchi, S. Das, A. Bhattacharya, R. Basu and P.
Nandy, “Nanocrystalline Mullite Synthesis at a Low
Temperature: Effect of Copper Ions,” Journal of the