Crystal structures of mixed-conducting oxides present in the Sr-Fe-Co-O system

摘要

The potential applications of mixed-conducting ceramic oxides include solid-oxide211u001efuel cells, rechargeable batteries, gas sensors and oxygen-permeable membranes. 211u001eSeveral perovskite-derived mixed Sr-Fe-Co oxides show not only high electrical-211u001econductivity but also appreciable oxygen-permeability at elevated temperatures. 211u001eFor example, dense ceramic membranes of SrFeCo(sub 0.5)O(sub 3(minus)(delta)) can 211u001ebe used to separate oxygen from air without the need for external electrical 211u001ecircuitry. The separated oxygen can be directly used for the partial oxidation of 211u001emethane to produce syngas. Quantitative phase analysis of the SrFeCo(sub 211u001e0.5)O(sub 3(minus)(delta)) material has revealed that it is predominantly 211u001ecomposed of two Sr-Fe-Co-O systems, Sr(sub 4)Fe(sub 6(minus)x)Co(sub x)O(sub 13) 211u001eand SrFe(sub 1(minus)x)Co(sub x)O(sub 3(minus)(delta)). Here we report 211u001epreliminary structural findings on the SrFe(sub 1(minus)x)Co(sub x)O(sub 211u001e3(minus)(delta)) (0 (le) x (le) 0.3) system.