MICROSCOPY Vol.45▶No.3 2010
â– Feature Articles: Towards a thorough Investigation of Material Science by Electron Holography

Observation of Inner Potential Distribution at Interfaces between Metal and Oxide Ion-Conductor

Takayoshi Tanji

Abstract: Electrostatic inner-potentials near the interfaces between Pt and oxide ion-conductor are measured by electron holography. The band bending inferred from the inner-potential distribution inside the proton conductor Strontium-Zirconium Oxide (SZO) supports the experimental result that the composite materials of Pt more than 1.5vol% in SZO show extremely low conductivity. Inner-potentials are also measured with applying external electric field to the model of fuel cell Pt/Gadolinium-doped Ceria (GDC)/Pt. In the result, an inhomogeneous distribution of Oxygen anions and ionic vacancies are detected in the condition no oxygen anions reserved. A new specimen holder has been developed so that specimen is applied external potential at high temperature.

Key words: fuel cell, oxide ion conductor, electron holography, in-situ observation