Electrochemical behavior of solid oxide fuel cell anodes based on infiltration of Y-doped SrTiO3

Abstract

Single cells based on yttrium-doped SrTiO3 (YST) infiltrated porous YSZ anodes were investigated as an alternative material for sulfur and carbon tolerant solid oxide fuel cells. First, a YSZ electrolyte-based cell with porous YSZ as the support for electrode materials on both sides was prepared. Then electrocatalyst materials were incorporated into the porous YSZ: the anode was infiltrated with YST precursor; and the cathode with LSM precursor to be heat treated in-situ. Heat treatment under reducing conditions was found to successfully eliminate the yttrium titanate impurity and to markedly reduce the YST crystal size. The results showed that there was an optimum amount of infiltrated YST to balance the conductivity and the polarization. Furthermore, the maximum power density under dry hydrogen at 900 °C was found to be 95 mW cm−2, which is greater than comparable reported values. H2S was found to have a promoting effect on the electrochemical performance of the fuel cell, particularly under methane. This work suggests that the infiltration technique can be successfully used not only to eliminate the complications associated with high temperature treatments required in conventional YST-YSZ anodes, but also to improve the electrochemical performance.