Electrical conductivity of Gd-doped ceria film at low temperatures (300–500 °C)

Gd-doped ceria (GDC, Ce1 − xGdxO2 − δ, x = 0.14–0.16) thin-films were deposited on sapphire substrate by RF-magnetron sputtering and their electrical conductivities of films were measured as a function of temperature (T = 300–500 °C) and oxygen partial pressure (Po2). All films showed columnar grains with crystallite size of 18–36 nm. The films annealed at high temperature and deposited from dense target exhibited their ionic conductivities similar to or higher than bulk GDC. The electronic conductivities of GDC films shown in low Po2 range, however, were higher than that of bulk GDC.