The structural and chemical evolution of propionate based low fluorine YBa2Cu3O7 − δ (YBCO) precursor during the conversion thermal treatment to obtain superconducting film has been investigated by both x-ray photoelectron and diffraction techniques in a set of partially converted films on SrTiO3 single crystals. The pyrolysis temperature within the range 400–480 °C mainly affects the copper valence state with an increase of the Cu2 + fraction with temperature with respect to the Cu1 + oxidation state. During the subsequent thermal treatment up to 700 °C, the reduction of fluorine content is mainly ascribed to the hydrolysis of YF3. At higher temperatures, Ba hydrolysis, Y2Cu2O5 and YBCO phase formation (nucleation at 700 °C and 725 °C, respectively) have been observed. The temperature dependences of the formation and decomposition of YBCO, Y2Cu2O5 and Ba-oxyfluoride were evaluated by x-ray diffraction measurements. The reaction path emerging from these analyses agrees with the one observed for YBCO films obtained with the standard MOD method based on metal tri-fluoroacetate precursors.
Angrisani Armenio, A., Augieri, A., Ciontea, L., . Contini, G., Davoli, I., Di Giovannantonio, M., et al. (2011). Structuraln and Chemical Evolution of Propionate based Metal-organic Precursor for Superconducting YBa2Cu3O7-d Epitaxial film growth. SUPERCONDUCTOR SCIENCE & TECHNOLOGY, 24(11), 115008 [10.1088/0953-2048/24/11/115008].
Structuraln and Chemical Evolution of Propionate based Metal-organic Precursor for Superconducting YBa2Cu3O7-d Epitaxial film growth
DAVOLI, IVAN;
2011-10-07
Abstract
The structural and chemical evolution of propionate based low fluorine YBa2Cu3O7 − δ (YBCO) precursor during the conversion thermal treatment to obtain superconducting film has been investigated by both x-ray photoelectron and diffraction techniques in a set of partially converted films on SrTiO3 single crystals. The pyrolysis temperature within the range 400–480 °C mainly affects the copper valence state with an increase of the Cu2 + fraction with temperature with respect to the Cu1 + oxidation state. During the subsequent thermal treatment up to 700 °C, the reduction of fluorine content is mainly ascribed to the hydrolysis of YF3. At higher temperatures, Ba hydrolysis, Y2Cu2O5 and YBCO phase formation (nucleation at 700 °C and 725 °C, respectively) have been observed. The temperature dependences of the formation and decomposition of YBCO, Y2Cu2O5 and Ba-oxyfluoride were evaluated by x-ray diffraction measurements. The reaction path emerging from these analyses agrees with the one observed for YBCO films obtained with the standard MOD method based on metal tri-fluoroacetate precursors.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.