Synthesis of BaZr _0.1 Ce _0.7 Y _0.2 O _3‐δ nano‐powders by aqueous gel‐casting for proton‐conducting solid oxide fuel cells

Abstract 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.