Stable proton-conducting Ca-doped LaNbo_4 thin electrolyte-based protonic ceramic membrane fuel cells by in situ screen printing

摘要

In order to develop a simple and cost-effective route to fabricate protonic ceramic membrane fuel cells (PCMFCs), a stable proton-conducting La_(0.99)Ca_(0.01) NbO_4 (LCN) thin electrolyte was fabricated on a porous NiO-La_(0.5)Ce_(0.5)O_(1.75) (NiO-LDC) anode by in situ screen printing. The key part of this process is to directly print well-mixed ink of La_2O_3, CaC03 and Nb_2O_5 instead of pre-synthesized LCN ceramic powder on the anode substrate. After sintering at 1400 deg C for 5 h, the full dense electrolyte membrane in the thickness of 20 mu m was obtained. A single cell was assembled with (La_(0.5)Sr_(0.2))_(0.9)MnO_((3-delta)-La_(0.5)Ce_(0.5)O_(0.75)(LSM-LDC) as cathode and tested with humidified hydrogen as fuel and static air as oxidant. The open circuit voltage (OCV) and maximum power density respectively reached 0.98V and 65mWcm~(-2) at 800 degg C Interface resistance of cell under open circuit condition was also investigated.