title: The origin of grain boundary capacitance in highly doped ceria.
abstract: The origin of a grain-boundary capacitance in mixed oxide-ion/electronic conductors has been investigated for the case of Ce0.8Sm0.2O1.9-δ using a.c. impedance spectroscopy under low pO2 from 250 to 400 °C. The observed capacitance is interpreted in terms of Ce(III):4f(1) electrons first introduced into the grains and not into the grain boundaries.
authors: Instituto de Química, Universidade de São Paulo, 05508-000, SP, Brazil. eccsouza@iq.usp.br.
authors: Eduardo Caetano C
authors: EC
authors: Souza
authors: Texas Materials Institute, The University of Texas at Austin, Austin, TX 78712, USA.
authors: John B
authors: JB
authors: Goodenough