Engineered nano-scale interfaces in scandia stabilized zirconia and samaria doped ceria multi-layer hetero-structures
EMSL Project ID
47691
Abstract
Recent studies showed a colossal enhancement in the oxygen ionic conductivity of multi-layer oxide thin films compared to most commonly used solid oxide fuel cell (SOFC) electrolytes. It has been observed that, the ionic conductivity of multi-layer oxide thin films increases with the increase in number of layers. The enhancement in the ionic conductivity of these multi-layer thin films was attributed to interfacial conductivity due to the lattice strain and extended defects near the interface. In the proposed study, we will investigate the influence of nano-scale interfaces on oxygen ionic conductivity in samaria doped ceria/ scandia stabilized zirconia (SDC/ScSZ) multi-layer thin films. In this study, the epitaxial SDC/ScSZ multi-layer thin films wiil be grown on Al2O3(0001) substrates by oxygen plasma-assisted molecular beam epitaxy (OPA-MBE) capability in EMSL. The growth of SDC/ScSZ multi-layer thin films will be carried out using the optimized growth conditions, dopant concentrations and film properties established for single-layer SDC and ScSZ epitaxial thin films in the previous studies conducted at EMSL. The number of layers in the multi-layer thin films will be varied by keeping the total film thickness constant to understand the influence of individual layer thickness on the ionic conductivity. The structure-property relationship of these multi-layer hetero-structures will be investigated using advanced spectroscopy, diffraction, and microscopy capabilities in EMSL. Oxygen ionic conductivity measurements through the films will be carried out as a function of temperature using four probe surface impedance spectroscopy. Theoretical studies will also be carried out using molecular dynamics simulations in conjunction with the experimental studies.
Project Details
Project type
Exploratory Research
Start Date
2012-12-03
End Date
2013-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members