Electronic Structural Optimization of the Air Electrodes for Reversible Protonic Ceramic Electrochemical Cells via IIIA Cation Doping

作者：Hao Liu, Wenjie Gong, Fan He, Yixuan Huang, Jiaojiao Xia, Xirui Zhang, Xiaofeng Chen, Kotaro Sasaki, YongMan Choi, Yu Chen · 发表于：ACS Energy Letters · 年份：2025 · DOI：10.1021/acsenergylett.5c02911 · 被引用次数：5 · 研究领域：Advancements in Solid Oxide Fuel Cells、Catalysis and Oxidation Reactions、Gas Sensing Nanomaterials and Sensors

Reversible protonic ceramic electrochemical cells (R-PCECs) have emerged as a novel technology for clean and efficient energy generation and storage. Improving the oxygen and proton conduction characteristics and stability of air electrodes at intermediate temperatures is crucial for achieving a high performance. Herein, we optimize the electronic structure of a state-of-the-art PrBa 0.8 Ca 0.2 Co 2 O 5+δ (PBCC) air electrode via doping IIIA cations (Al 3+, Ga 3+, and In 3+ ). It is shown that PrBa 0.8 Ca 0.2 Co 1.9 Ga 0.10 O 5+δ (PBCCGa 0.10 ) exhibits improved oxygen reaction activity and hydration capability. Density functional theory calculations confirm that Ga doping provides the most favorable electronic structure. An R-PCEC with PBCCGa 0.10 achieves a peak power density of 2.21 W cm –2 and a current density of −4.64 A cm –2 at 1.3 V at 650 °C. Additionally, the PBCCGa 0.10 electrode performs good operational stability in FC mode (for about 100 h), EC mode (for about 100 h), and reversible cyclic testing (over 200 h) at 600 °C.