Synthesis of BaZr0.1Ce0.7Y0.2O3-δ nano-powders by aqueous gel-casting for proton-conducting solid oxide fuel cells

For the sake of enhance the sinter ability and electrical conductivity of BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY) electrolytes, a modified aqueous gel-casting method was applied to synthesize high sintering active and high conductive BZCY nano-powders. The new approach makes it easy to obtain pure perovskite. The highly sintering active purity-phase of BZCY nano-powder (particle size of 50∼100 nm) was obtained by calcining at 1100°C for 2 h. Nano-powders effectively reduce the sintering densification temperature and successfully prepare BZCY electrolyte with relative density > 96 % at 1450°C, and promote grain growth with an average grain size of 2.36 μm. Benefiting from this, improved electrical conductivities (e.g., 12.4×10 −3 S cm −1 at 700°C, in wet air) are obtained. The NiO-BZCY/BZCY/LSCF-BZCY anode-supporting single cell shows a peak power density of 0.75 W cm −2 at 700°C while taking ambient air as oxidants and wet H 2 (∼3 vol.% H 2 O) as fuels.