An Efficient Trifunctional Spinel‐Based Electrode for Oxygen Reduction/Evolution Reactions and Nonoxidative Ethane Dehydrogenation on Protonic Ceramic Electrochemical Cells
Yangsen Xu, Hua Zhang, Kang Xu, Xirui Zhang, Feng Zhu, Wanqing Deng, Fan He, Ying Liu, Yu Chen
Abstract
Abstract Protonic ceramic electrochemical cells (PCECs) have received considerable attention as they can directly generate electricity and/or produce chemicals. Development of the electrodes with the trifunctionalities of oxygen reduction/evolution and nonoxidative ethane dehydrogenation is yet challenging. Here these findings are reported in the design of trifunctional electrodes for PCECs with a detailed composition of Mn 0.9 Cs 0.1 Co 2 O 4‐δ (MCCO) and Co 3 O 4 (CO) (MCCO–CO, 8:2 mass ratio). At 600 °C, the MCCO–CO electrode exhibits a low area‐specific resistance of 0.382 Ω cm 2 and reasonable stability for ≈105 h with no obvious degradation. The single cell with the MCCO–CO electrode shows an encouraging peak power density of 1.73 W cm −2 in the fuel cell (FC) mode and a current density of ‐3.93 A cm −2 at 1.3 V in the electrolysis cell (EC) mode at 700 °C. Moreover, the MCCO–CO cell displays promising operational stability in FC mode (223 h), EC mode (209 h), and reversible cycling stability (52 cycles, 208 h) at 650 °C. The MCCO–CO single cell shows an encouraging ethane conversion to ethylene (with a conversion of 40.3% and selectivity of 94%) and excellent H 2 production rates of 4.65 mL min −1 cm −2 at 1.5 V and 700 °C, respectively, with reasonable Faradaic efficiencies.