TY - JOUR
T1 - High-quality ceramics of YBa2Cu4O8 from citrate sol-gel precursors sintered at one atmosphere oxygen pressure
AU - Kakihana, Masato
AU - Käll, Mikael
AU - Börjesson, Lars
AU - Mazaki, Hiromasa
AU - Yasuoka, Hiroshi
AU - Berastegui, Pedro
AU - Eriksson, Sten
AU - Johansson, Lars Gunnar
N1 - Funding Information:
This work was partially supported by the Swedish Natural Science Research Council and the Swedish Board for Technical Development.
PY - 1991/2/15
Y1 - 1991/2/15
N2 - Single phase ceramic material of the superconducting phase YBa2Cu4O8 has been synthesized at 780-790°C under one atmosphere oxygen pressure with a sol-gel powder precursor technique. The precursor was derived from citrate metal ion complexes uniformly dispersed in a solvent mixture of ethyleneglycol and water. The main advantages of the present method are, apart from the low oxygen pressure needed, the elimination of centrifugation, ageing and fine control of pH usually required for other solution techniques. X-ray diffraction analysis show that the material is virtually of single-phase character with only minor traces of CuO (∼1%). AC-susceptibility measurements indicate a high-quality sample with an onset of the superconducting transition at Tc=82.6 K. The superconducting transition is much sharper, ΔTc(10-90%)=4.5K, than for ceramic samples of previously reported synthesis procedures.
AB - Single phase ceramic material of the superconducting phase YBa2Cu4O8 has been synthesized at 780-790°C under one atmosphere oxygen pressure with a sol-gel powder precursor technique. The precursor was derived from citrate metal ion complexes uniformly dispersed in a solvent mixture of ethyleneglycol and water. The main advantages of the present method are, apart from the low oxygen pressure needed, the elimination of centrifugation, ageing and fine control of pH usually required for other solution techniques. X-ray diffraction analysis show that the material is virtually of single-phase character with only minor traces of CuO (∼1%). AC-susceptibility measurements indicate a high-quality sample with an onset of the superconducting transition at Tc=82.6 K. The superconducting transition is much sharper, ΔTc(10-90%)=4.5K, than for ceramic samples of previously reported synthesis procedures.
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U2 - 10.1016/0921-4534(91)90738-K
DO - 10.1016/0921-4534(91)90738-K
M3 - Article
AN - SCOPUS:0026105194
VL - 173
SP - 377
EP - 380
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
SN - 0921-4534
IS - 5-6
ER -