An oxygen sensor includes an epitaxial oxide thin film double perovskite oxygen sensor formed on a single crystal oxide substrate. The thin film includes a lanthanide element, barium, cobalt, and oxygen.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with government support under grant no. 0709293 awarded by the National Science Foundation and grant no. DE-FG26-07NT43063 awarded by the U.S. Department of Energy. The government has certain rights in the invention.