@article{Liu_Tang_Song_Yang_Qian_Yang_Zhu_Ran_Wang_Zhou_Shao_2022, title={High-Entropy Perovskite Oxide: A New Opportunity for Developing Highly Active and Durable Air Electrode for Reversible Protonic Ceramic Electrochemical Cells}, volume={14}, url={https://nmlett.org/index.php/nml/article/view/1214}, DOI={10.1007/s40820-022-00967-6}, abstractNote={<p>Reversible proton ceramic electrochemical cell (R-PCEC) is regarded as the most promising energy conversion device, which can realize efficient mutual conversion of electrical and chemical energy and to solve the problem of large-scale energy storage. However, the development of robust electrodes with high catalytic activity is the main bottleneck for the commercialization of R-PCECs. Here, a novel type of high-entropy perovskite oxide consisting of six equimolar metals in the A-site, Pr<sub>1/6</sub>La<sub>1/6</sub>Nd<sub>1/6</sub>Ba<sub>1/6</sub>Sr<sub>1/6</sub>Ca<sub>1/6</sub>CoO<sub>3−<em>δ</em></sub> (PLNBSCC), is reported as a high-performance bifunctional air electrode for R-PCEC. By harnessing the unique functionalities of multiple elements, high-entropy perovskite oxide can be anticipated to accelerate reaction rates in both fuel cell and electrolysis modes. Especially, an R-PCEC utilizing the PLNBSCC air electrode achieves exceptional electrochemical performances, demonstrating a peak power density of 1.21&nbsp;W&nbsp;cm<sup>−2</sup> for the fuel cell, while simultaneously obtaining an astonishing current density of − 1.95&nbsp;A&nbsp;cm<sup>−2</sup> at an electrolysis voltage of 1.3&nbsp;V and a temperature of 600&nbsp;°C. The significantly enhanced electrochemical performance and durability of the PLNBSCC air electrode is attributed mainly to the high electrons/ions conductivity, fast hydration reactivity and high configurational entropy. This research explores to a new avenue to develop optimally active and stable air electrodes for R-PCECs.</p> <p>Highlights:</p> <p>1 Synthesis of high-entropy perovskite oxide for air electrode in reversible proton ceramic electrochemical cells.<br>2 Triple-conducting high-entropy air electrodes exhibit excellent structural stability and oxygen catalytic activity.<br>3 The peak power density and current density of the cell with high-entropy air electrode in the fuel cell and electrolysis modes are 1.21 W cm<sup>−2</sup> and − 1.95 A cm<sup>−2</sup> at 600 °C, respectively.</p>}, journal={Nano-Micro Letters}, author={Liu, Zuoqing and Tang, Zhengjie and Song, Yufei and Yang, Guangming and Qian, Wanru and Yang, Meiting and Zhu, Yinlong and Ran, Ran and Wang, Wei and Zhou, Wei and Shao, Zongping}, year={2022}, month={Nov.}, pages={217} }