Thermal stability of SrFeO3/Al2O3 thin films: Transmission electron microscopy study and conductometric sensing response

Abstract

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Strain-Induced Anisotropic Transport Properties of LaBaCo2O5.5+δ Thin Films on NdGaO3 Substrates

“…Complex transition-metal oxides have attracted considerable attention of research due to their electrical, magnetic, and optical properties, which can be used for the development of various new concept devices, such as energy harvest, electrical, and chemical sensors, etc. − Perovskite cobaltates exhibit remarkable mixed conductivity and catalytic properties at high temperature as well as interesting magnetic and electrical transport properties at low temperature. − Among them, the oxygen-deficient double perovskite cobaltates LnBa­Co 2 O 5.5+δ (Ln = Lanthanide) show particularly interesting phenomena of the order–disorder at the A-cation sites in the cobaltate system. − Especially, the very small difference in the A-site cations’ radii between La 3+ and Ba 2+ in the LaBa­Co 2 O 5.5+δ (LBCO) can form complex A-site order, nanoarea order, and disorder layered perovskite structures and induce various exciting physical phenomena, such as various oxidation states (Co 2+ /​Co 3+ /Co 4+ ) of cobalt, different spin state configurations, giant MR effect, metal insulator transition, etc. − In order to fully understand the magnetic and transport properties of such complex cobalt oxides, the single crystalline samples are critically desired. In our previous work, we have fabricated highly epitaxial single crystalline LBCO thin films on (001) LaAlO 3 , , (001) SrTiO 3 , , and (001) MgO and found that these films possess an extraordinary sensitivity to reducing/oxidizing environments and an exceedingly fast redox reaction at high temperature.…”

Epitaxial Nature and Transport Properties in (LaBa)Co2O5+δ Thin Films

“…Mixed ionic/electronic conducting materials are of increasing interest owing to their potential applications in various novel devices such as ceramic membranes, ultra sensitive chemical sensor, partial oxidation reactors as well as electrodes in solid oxide fuel cell (SOFC). − To improve the performance of those devices, the mixed ionic electronic conducting materials should meet the requirements of both high oxygen diffusivity and great enhancement of surface exchange rate, , These two desirable attributes are typically found in the oxygen deficient doped perovskite cobaltates (Re,A)Co 2 O 5+δ , where Re is a rare earth element and A is an alkaline earth element. The A-site cation average valence favors a compensating population of oxygen vacancies at low oxygen partial pressures and therefore leads to the observed high ionic conductivity.…”

Manipulation of Optical Transmittance by Ordered-Oxygen-Vacancy in Epitaxial LaBaCo2O5.5+δ Thin Films

“…Especially, the remarkable mixed conductivity and catalytic properties at high temperature and exciting magnetic and electrical transport properties at low temperature have been intensively studied by scientists and technicians89. All these excellent physical properties have encouraged people to design lots of kinds of functional devices, including solid oxide fuel cells, energy harvest devices, electrical and chemical sensors, etc10111213.…”