Abstract
Magnesium oxide (MgO) whiskers (with diameters of about 60–80 nm) formed on the surface of bulk polycrystalline MgB2 superconductor at a relative low temperature (720 °C) during in situ sintering process. The reaction between Mg and B powders begins at a temperature below melting point of Mg and maintains till about 750 °C. The residual Mg powders evaporate and react with trace oxygen to form MgO vapor as the temperature exceeds the melting temperature of Mg and a low supersaturation is required for the growth of MgO whiskers. The preformed MgB2 and MgO crystals act as substrates and the melted Mg powders on the surface of them serve as catalysts during the growth process of MgO whiskers. The growth process of MgO whiskers is dominated by a self-catalytic vapor–liquid–solid (VLS) mechanism.
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Hkanson DF, Hoover SM, Crowe CR (1985) J Mater Sci 20:4147. doi: https://doi.org/10.1007/BF00552410
Kondilis P, Mousdis G, Kordas G (1994) Phys C Supercond 235:467
Yuan YS, Wong MS, Wang SS (1995) Phys C Supercond 250:247
Yuan YS, Wong MS, Wang SS (1996) J Mater Res 11:1373
Kordas G (2000) J Mater Chem 10:1157
Saitoh H, Okada Y, Ohshio S (2002) J Mater Sci 37:4597. doi: https://doi.org/10.1023/A:1020696215411
Nagamatsu J, Nakagawa N, Muranaka T, Zenitani Y, Akimitsu J (2001) Nature 410:63
Delin Y, Hongwei S, Hongxia L et al (2003) Supercond Sci Technol 16:576–581
Yadong Y, Guangtao Z, Younan X (2002) Adv Funct Mater 12:293–298
Levitt AP (1997) Whisker technology, army materials and mechanics research center Watertown. Massachusetts, New York, London, p 37
Lee JS, Park K, Nahm S, Kim SW, Kim S (2002) J Cryst Growth 244:287
Duan XF, Lieber CM (2000) Adv Mater 12:298
Chen XL, Li JY, Cao YG, Lan YC et al (2000) Adv Mater 12:1432
Cui Y, Laucoln LJ, Gudiksen MS et al (2001) Appl Phys Lett 78:2214
Chen CC, Yeh CC, Chen CH et al (2001) J Am Chem Soc 123:2791
Chen CC, Yeh CC (2000) Adv Mater 12:738
Gao PX, Wang ZL (2003) Nano Lett 3:1315
Ding Y, Gao PX, Wang ZL (2004) J Am Chem Soc 126:2066
Pan ZW, Dai ZR, Ma C, Wang ZL (2002) J Am Chem Soc 124:1817
Sunkara MK, Sharma S, Miranda R et al (2001) Appl Phys Lett 79:1546
Chen YJ, Li JB, Han YS, Yang XZ, Dai JH (2002) J Cryst Growth 245:163–170
Bakulina VM, Tokareva SA, Latysheva EI (1970) J Struct Chem 11(1):150–151
Dang HY, Wang J, Fan SS (2003) Nanotechnology 14:738
Stach EA, Pauzauskie PJ, Kuykendall T et al (2003) Nano Lett 3:867
Jian JK, Wang C, Zhang ZH et al (2006) Mater Lett 60:3809
Wu Y, Yang P (2001) J Am Chem Soc 123:3165
Acknowledgements
The authors would like to thank the National Nature Science Foundation of China (granted No. 50401003), the Natural Science Foundation of Tianjin City (granted No. 07JCZDJC01200), the Keygrant Project of Chinese Ministry of Education (granted No. 707012) and Program for New Century Excellent Talents in University for financial support.
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Shi, Q., Liu, Y., Gao, Z. et al. Formation of MgO whiskers on the surface of bulk MgB2 superconductors during in situ sintering. J Mater Sci 43, 1438–1443 (2008). https://doi.org/10.1007/s10853-007-2306-2
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DOI: https://doi.org/10.1007/s10853-007-2306-2