SrCe_0.9In_0.1O_3-δ-based reversible symmetrical Protonic Ceramic Cell

In-doped SrCe_0.9In_0.1O_3-δ (SCI) perovskite-type oxide is utilized as the solid electrolyte, as well as a component, together with SrFe_0.75Mo_0.25O_3-δ (SFM) compound, in the composite-type electrodes to construct symmetrical Protonic Ceramic Fuel Cells (PCFC). With good mutual stability of SCI and SFM at high temperatures in water vapor-containing reducing and oxidizing conditions, as well as sufficient ionic conductivity with high proton transference number of SrCe_0.9In_0.1O_3-δ, and high electronic conduction of SrFe_0.75Mo_0.25O_3-δ, effectiveness of the electrochemical reactions is ensured. It is documented that 80:20 wt.% SFM-SCI electrode performs better, comparing to the one having 50:50 wt.% ratio of both compounds, with both electrodes showing lower polarization resistance values in the reducing conditions. Symmetrical SCI-SFM|SCI|SCI-SFM cells can be operated in normal (PCFC) and reversed, Protonic Ceramic Electrolyzer Cell (PCEC) mode, showing similar shape of current density-voltage characteristics. The maximum obtained power density is 32 mW cm⁻² at 800 °C.