Redox Stability and Conductivity of Nb Doped SrTiO3 for SOFC Anodes

Michael A. Deighan1, Addison Z. Yee2, and Michael D. Gross1. (1) Chemical Engineering, Bucknell University, Lewisburg, PA 19610, (2) Mechanical Engineering, Bucknell University, Lewisburg, PA 19610

This study investigated the development of novel electronically conductive ceramic materials for use in redox-stable solid oxide fuel cell (SOFC) anodes. The conductivity of bulk SrNbxTi1-xO3 (SNT), for x = 0.05, 0.1, and 0.2, was measured for samples sintered in air as well as samples sintered under reducing conditions. The conductivity of reduced bulk samples was measured to be of order 10 S/cm under relevant fuel cell operating and redox conditions. In addition, the electronic conductivity of porous SNT/yttria-stabilized zirconia (YSZ) composites was measured to be of order 1 S/cm. All samples sufficiently maintained conductivity with redox cycling at 973 K and 1073 K. X-ray diffraction (XRD) data suggest the SNT and YSZ do not react, indicating compatibility of the composite materials.