Constructing highly active and durable oxygen electrode by nanoengineering for reversible protonic ceramic cell
Junmeng Jing, Ze Lei, Yuhan Xue, Ziwei Zheng, Haoran Wang, Panpan Zhang, Ben Ge, Zhibin Yang
Abstract
Reversible protonic ceramic cell (R-PCC) is a cost-effective and efficient energy storage and conversion system, yet the commercialization of R-PCC is hindered by the sluggish reaction kinetics of oxygen electrodes. Here, findings that dramatically enhance the reaction activity and stability of Ba 0.95 La 0.05 Fe 0.8 Zn 0.2 O 3−δ -BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3−δ (BLFZ-BZCYYb) oxygen electrode by PrO x nanoparticles coating are reported. PrO x -coated BLFZ-BZCYYb electrode exhibits a 55% decrease in polarization resistance at 650 °C (compared to the bare electrode). The R-PCC with PrO x -coated electrode demonstrates an excellent performance in fuel cell (peak power density of 0.747 W cm −2 @650 °C) and electrolysis (current density of 0.773 A cm −2 at 650 °C and 1.3 V) modes. Furthermore, the cell exhibits good cycling stability in dual fuel cell and electrolysis modes after 60 cycles at 650 °C. The performance improvement is ascribed to a synergistic effect of PrO x (accelerated O 2 dissociation) and triple conducting BLFZ, as confirmed by electrochemical impedance spectroscopy and computations.