Large-scale tubular protonic ceramic electrolysis cells made by injection molding

Abstract

Protonic ceramic electrochemical cells (PCCs) are potential candidates for efficient hydrogen production at intermediate temperature (∼400–600 °C). However, their development has been limited to the laboratory scale. Here, we report the first demonstration of large-scale tubular PCCs via ceramic injection molding. NiO-BaCe_0.7Zr_0.1Y_0.1Yb_0.1O_3-d (BCZYYb7111) closed-end negatrode supports are injection-molded into uniform, straight tubes with a diameter of 1.5 cm and lengths up to 17.5 cm; the BCZYYb7111 electrolyte is then dip-coated and co-sintered. Microstructural analysis confirms homogeneous phase distribution, well-controlled porosity in the reduced negatrode, and a high-quality, dense, and crack-free electrolyte with exceptionally large grain size (∼50 µm) and thicknesses between 24 and 30 µm. Under electrolysis operation, these tubes achieve current densities up to 400 mA cm⁻² at 1.3 V and 650 °C. Stable operation for 50 hours at 250 mA cm⁻² and 550 °C is also demonstrated.