From Powdered Oxide to Shaped Metal: an Easy Way to Prepare a Porous Metallic Alloy for SOFC

Abstract

This work reports a proof of concept to obtain a shaped porous metallic alloy by the reduction at low temperature of an oxide precursor shaped at high temperature. A mixed cations oxide selected for potential applications in solid oxide fuel cells (SOFCs), is prepared using Pechini's polymer route and consolidated using the spark plasma sintering (SPS) technique at temperature in the 900 °C – 1,100 °C range. A pellet of pure AB2O4 spinel‐like structure with 10% of open porosity is obtained. The reduction of this pellet under H2 flow at low temperature (800 °C) allows obtaining a highly porous (48%) metallic pellet which meets all necessary characteristics to be used as mechanical support for the third generation of SOFC (3G‐SOFC). The use of oxide precursors widen the accessible temperature range allowing the possibility to stack in one step an oxide precursor of the 3G‐SOFC with full densification of the electrolyte. This proof of concept opens the way to the easy and cheap “one step” building of an oxide precursor of 3G‐SOFC which will be in situ activated during the warming up of the cell.