TY - JOUR
T1 - Fabrication and electrochemical properties of epitaxial samarium-doped ceria films on SrTiO3-buffered MgO substrates
AU - Sanna, Simone
AU - Esposito, Vincenzo
AU - Pergolesi, Daniele
AU - Orsini, Andrea
AU - Tebano, Antonello
AU - Licoccia, Silvia
AU - Balestrino, Giuseppe
AU - Traversa, Enrico
PY - 2009/6/9
Y1 - 2009/6/9
N2 - Thin films of samarium-oxide-doped (20 mol%) ceria (SDC) are grown by pulsed-laser deposition (PLD) on (001) MgO single-crystal substrates. SrTiO 3 (STO) prepared by PLD is used as a buffer layer on the MgO substrates to enable epitaxial growth of the fluorite-structured SDC film; the STO layer provides a proper crystalline match between SDC and MgO, resulting in highly crystalline, epitaxial SDC films grown in the (001) orientation. Film conductivity is evaluated by electrochemical impedance spectroscopy measuremensts, which are performed at various temperatures (400-775°C) in a wide range of oxygen partial pressure (pO2) values (10 -25-1 atm) in order to separate ionic and electronic conductivity contributions. At 700°C, SDC/STO films on (100) MgO exhibit a dominant ionic conductivity of about 7×10-2S cm-1, down to pO 2 values of about 10-15 atm. The absence of grain boundaries make the SDC/STO/MgO heterostructures stable to oxidation-reduction cycles at high temperatures, in contrast to that observed for the more disordered SDC/STO films, which degraded after hydrogen exposure.
AB - Thin films of samarium-oxide-doped (20 mol%) ceria (SDC) are grown by pulsed-laser deposition (PLD) on (001) MgO single-crystal substrates. SrTiO 3 (STO) prepared by PLD is used as a buffer layer on the MgO substrates to enable epitaxial growth of the fluorite-structured SDC film; the STO layer provides a proper crystalline match between SDC and MgO, resulting in highly crystalline, epitaxial SDC films grown in the (001) orientation. Film conductivity is evaluated by electrochemical impedance spectroscopy measuremensts, which are performed at various temperatures (400-775°C) in a wide range of oxygen partial pressure (pO2) values (10 -25-1 atm) in order to separate ionic and electronic conductivity contributions. At 700°C, SDC/STO films on (100) MgO exhibit a dominant ionic conductivity of about 7×10-2S cm-1, down to pO 2 values of about 10-15 atm. The absence of grain boundaries make the SDC/STO/MgO heterostructures stable to oxidation-reduction cycles at high temperatures, in contrast to that observed for the more disordered SDC/STO films, which degraded after hydrogen exposure.
UR - http://www.scopus.com/inward/record.url?scp=67649206066&partnerID=8YFLogxK
U2 - 10.1002/adfm.200801768
DO - 10.1002/adfm.200801768
M3 - Article
AN - SCOPUS:67649206066
SN - 1616-301X
VL - 19
SP - 1713
EP - 1719
JO - Advanced Functional Materials
JF - Advanced Functional Materials
IS - 11
ER -