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Contemporary Materials I−1 (2010)

Contemporary Materials, I–1 (2010)     Page 61 - 67

UDK 544.4:66.01

SYNTHESIS OF Ba0.5Sr0.5Co0.8Fe0.2O3 − δ FROM DIFFERENT PRECURSOR MATERIALS EMPLOYING MICROWAVE HEATING

S. Zeljković1, J. Penavin-Škundrić1, T. Ivas2, S. Vaucher3

1 University of Banja Luka,  Faculty of Science and Mathematics, Mladena Stojanovića 2, 78000  Banja Luka, Bosnia and Herzegovina
2 Nonmetallic Inorganic Materials, Department of Materials, ETH-Zurich, Wolfgang-Pauli-Strasse 10, HCI G 530, CH-8093 Zurich, Switzerland
3 EMPA - Swiss Federal Laboratories for Materials Science and Technology, Advanced Material Processing, Feuerwerkerstrasse 39, CH-3602 Thun, Switzerland

Abstract

Ba0.5Sr0.5Co0.8Fe0.2O3-δ pow­ders with pe­rov­ski­te struc­tu­re ha­ve been synthesized from dif­fe­rent mix­tu­res of ni­tra­te, oxi­de and car­bo­na­te pre­cur­sors, ir­ra­di­a­ted in a mic­ro­wa­ve oven with 2.45 GHz and va­ri­o­us po­wer out­puts. The mic­ro­wa­ve synthe­sis was car­ried out in oxygen at­mosp­he­re. The ef­fects of ra­pid mic­ro­wa­ve he­a­ting we­re evalu­a­ted ma­inly by com­pa­ring the sta­te of materials be­fo­re and af­ter mic­ro­wa­ve exposure. Different pre­cur­sors we­re eva­lu­a­ted ac­cor­ding to the­ir sen­si­ti­vity to mic­ro­wa­ve fi­eld and to­xi­city of bypro­ducts. The lo­wer tem­pe­ra­tu­re and shor­ter ti­me for Ba0.5Sr0.5Co0.8Fe0.2O3-δ synthe­sis with mic­ro­wa­ve ir­ra­di­a­tion might be ascri­bed to the activa­ting and fa­ci­li­ta­ting ef­fect of mic­ro­wa­ve on so­lid pha­se dif­fu­sion. Mic­ro­wa­ve irradi­a­tion is pro­ved to be a no­vel, ti­me-sa­ving and energy-ef­fi­ci­ent ro­u­te to the synthe­sis of Ba0.5Sr0.5Co0.8Fe0.2O3-δ pow­der.

Keywords: Ba0.5Sr0.5Co0.8Fe0.2O3-δ, pe­rov­ski­te, synthe­sis, cal­ci­na­ti­ons, con­ven­ti­o­nal heating. 

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References

[1] Z. Shao, W. Yang, Y. Cong, H. Dong, J. Tong, G. Xiong, Investigation of the permeation behavior and stability of a Ba0.5Sr0.5Co0.8Fe0.2O3−δ oxy-gen membrane, J. Membr. Sci.172 (2000) 177–188.
[2] H. Wang, Y. Cong, W. Yang, J. Membr. Sci. 210 (2002) 259–271.
[3] Z. Shao, G. Xiong, H. Dong, W. Yang, L. Lin, Synthesis, oxygen permeation study and memb-rane performance of a Ba0.5Sr0.5Co0.8Fe0.2O3−δ oxy-gen-permeable dense ceramic reactor for partial oxidation of methane to syngas, Sep. Purif. Technol. 25 (2001) 97–116.
[4] H. Wang, Y. Cong, W. Yang, Investigation on the partial oxidation of methane to syngas in a tubular Ba0.5Sr0.5Co0.8Fe0.2O3−δ membrane reactor, Catal. Today, 82 (2003) 157–166.
[5] H. Wang, Y. Cong, W. Yang, Partial oxidation of ethane to syngas in an oxygen-permeable membrane reactor, J. Membr. Sci. 209 (2002) 143–152.
[6] Z. Shao, S.M. Haile, A High Performance Cathode for the Next Generation Solid-Oxide Fuel Cells, Nature 431 (2004) 170–173. PMid:15356627
[7] A. Yan, M. Cheng, Y. Dong, W. Yang, V. Maragou, S. Song, P. Tsiakaras, Investigation of a Ba0.5Sr0.5Co0.8Fe0.2O3−δ based cathode IT-SOFC: I. The effect of CO2 on the cell performance, Appl. Catal. B, 66 (2006) 64–71.
[8] S. Zeljković, J. Penavin Škundrić, T. Ivas, Synthesis and characterization of selected BSCF ceramics of the perovskite type produced by conventio-nal heating, Proceedings of „Contemporary mate-rials“ (2010) 259–277.
[9] H. Sobol, K. Tomiyasu, Milestones of mic-rowaves, IEEE T. Microw. Theory, 50 (2002) 594–611.
[10] J. M. Osepchuk, Microwave power applications, IEEE T. Microw. Theory, 32 (1984) 1200–1224.
[11] A.W. Guy, History of biological effects and medical applications of microwave energy, IEEE T. Microw. Theory, 32 (1984) 1182-1200.
[12] D. F. Stein, “Microwave Processing of Materials”, Cometee on Microwave Procesing of Materials, National Materials Advisory Board (1994).
[13] D. E. Clark, W. H. Suton, Microwave Processing of Materials, Annu. Rev. Mater. Sci., 26 (1996) 299-331.
[14] S. Zeljković, S. Vaucher, J. Penavin-Škundrić, T. Ivas, Evaluation of Microwave heating for the synthesis and sintering of La0.7Sr0.3FeO3+δ perovskite composition, Proceedings of 38th IOCMM (2006) 563–568.