A Simple and Cost‐Effective Approach to Fabrication of Dense Ceramic Membranes on Porous Substrates

A simple and elegant approach to fabrication of dense ceramic membranes on porous substrates, a traditional dry pressing of foam powders, has been developed to reduce the cost of fabrication. Gd‐doped ceria (GDC, Gd 0.1 Ce 0.9 O 1.95 ) electrolyte membranes as thin as 8 μm are obtained by dry‐pressing highly porous GDC powders. The membrane thickness can be readily controlled by the amount of powder. The electrolyte membranes are studied in a solid‐oxide fuel cell (SOFC) with air as oxidant and humidified hydrogen (3% H 2 O) as fuel. Open‐circuit voltages of about 1.0 V are observed, implying that the permeability of the membranes to molecular gases is insignificant. Power densities of 140 and 380 mW/cm 2 are demonstrated at 500° and 600°C, respectively, representing a significant progress in developing low‐temperature SOFCs.