Fabrication of BaZr(0.1)Ce_(0.7)Y_(0.2)O_(3-δ) - Based Proton-Conducting Solid Oxide Fuel Cells Co-Fired at 1,150℃

摘要

Dense proton-conducting BaZr_(0.1)Ce_(0.7)Y_(0.2)O_(3-δ) (BZCY) electrolyte membranes were successfully fabricated on NiO-BZCY anode substrates at a low temperature of 1,150℃ via a combined co-press and co-firing process. To fabricate full cells, the LaSr_3Co_(1.5)Fe_(1.5)O(10-δ)-BZCY composite cathode layer was fixed to the electrolyte membrane by two means of one-step co-firing and two-step co-firing, respectively. The SEM results revealed that the cathode layer bonded more closely to the electrolyte membrane via the one-step co-firing process. Correspondingly, determined from the electrochemical impedance spectroscopy measured under open current conditions, the electrode polarisation and Ohmic resistances of the one-step co-fired cell were dramatically lower than the other one for its excellent interface adhesion. With humidified hydrogen (2% H_2O) as the fuel and static air as the oxidant, the maximum power density of the one-step co-fired single cell achieved 328 mW cm~(-2) at 700℃, showing a much better performance than that of the two-step co-fired single cell, which was 264 mW cm~(-2) at 700℃.