Reversible protonic ceramic electrochemical cells (R-PCECs) have a good application prospect as the energy conversion and storage devices. The electrode surface kinetics (i.e., oxygen reduction reaction (ORR) and water oxidation reaction (WOR)) are major technical obstacles to developing the R-PCECs. Here, we report a phase-pure Pd-doped double perovskite with a PrBaCaCoPdO (PBCCPd) formula. The PBCCPd air electrode displays a polarization resistance () of 0.056 Ω cm in the BZCYYb-based symmetrical cell at 700 °C, and also performs a peak power density (PPD) of 2.08 W cm using the fuel cell mode, and a current density of -4.42 A cm at 1.3 V using the electrolysis cell mode at 700 °C. Moreover, R-PCECs with PBCCPd air electrodes show excellent stability in fuel and electrolysis cells, and cycling modes with reasonable Faradaic efficiency. It is shown that Pd doping can effectively increase the oxygen vacancy, improve the oxygen surface exchange, bulk diffusion capabilities, and electrocatalytic activity and stability in the air electrode of R-RCECs, indicated by the X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectra (EIS), electrical conductivity relaxation (ECR), and distribution of relaxation time (DRT).

中文翻译：

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用于可逆质子陶瓷电化学电池的活性双功能钯掺杂双钙钛矿空气电极

可逆质子陶瓷电化学电池（R-PCECs）作为能量转换和存储装置具有良好的应用前景。电极表面动力学（即氧还原反应（ORR）和水氧化反应（WOR））是开发R-PCEC的主要技术障碍。在这里，我们报道了一种具有 PrBaCaCoPdO (PBCCPd) 公式的纯相 Pd 掺杂双钙钛矿。 PBCCPd空气电极在700°C下在基于BZCYYb的对称电池中显示出0.056Ω·cm的极化电阻（），并且使用燃料电池模式还表现出2.08W·cm的峰值功率密度（PPD）和电流密度使用电解池模式在 700 °C 下在 1.3 V 下为 -4.42 A cm。此外，具有 PBCCPd 空气电极的 R-PCEC 在燃料电池和电解电池中表现出优异的稳定性，并且具有合理的法拉第效率的循环模式。 X射线光电子能谱（XPS）、电化学分析表明，Pd掺杂可以有效增加氧空位，提高R-RCEC空气电极的氧表面交换、体扩散能力以及电催化活性和稳定性。阻抗谱 (EIS)、电导率弛豫 (ECR) 和弛豫时间分布 (DRT)。