Pei Kai, Zhou Yucun, Xu Kang, Zhang Hua, Ding Yong, Zhao Bote, Yuan Wei, Sasaki Kotaro, Choi YongMan, Chen Yu, Liu Meilin
School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.
School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30309, USA.
Nat Commun. 2022 Apr 22;13(1):2207. doi: 10.1038/s41467-022-29866-5.
Reversible protonic ceramic electrochemical cells (R-PCECs) are ideally suited for efficient energy storage and conversion; however, one of the limiting factors to high performance is the poor stability and insufficient electrocatalytic activity for oxygen reduction and evolution of the air electrode exposed to the high concentration of steam. Here we report our findings in enhancing the electrochemical activity and durability of a perovskite-type air electrode, BaCoFeNbO (BCFN), via a water-promoted surface restructuring process. Under properly-controlled operating conditions, the BCFN electrode is naturally restructured to an Nb-rich BCFN electrode covered with Nb-deficient BCFN nanoparticles. When used as the air electrode for a fuel-electrode-supported R-PCEC, good performances are demonstrated at 650 °C, achieving a peak power density of 1.70 W cm in the fuel cell mode and a current density of 2.8 A cm at 1.3 V in the electrolysis mode while maintaining reasonable Faradaic efficiencies and promising durability.
可逆质子陶瓷电化学电池（R-PCEC）非常适合高效的能量存储和转换；然而，高性能的限制因素之一是暴露于高浓度蒸汽中的空气电极稳定性差以及氧还原和析出的电催化活性不足。在此，我们报告了通过水促进的表面重构过程提高钙钛矿型空气电极BaCoFeNbO（BCFN）的电化学活性和耐久性的研究结果。在适当控制的操作条件下，BCFN电极自然重构为覆盖有缺铌BCFN纳米颗粒的富铌BCFN电极。当用作燃料电极支撑的R-PCEC的空气电极时，在650°C下表现出良好的性能，在燃料电池模式下实现了1.70 W cm的峰值功率密度，在电解模式下在1.3 V时实现了2.8 A cm的电流密度，同时保持了合理的法拉第效率和良好的耐久性。
