Zhu Kang, Yang Yi, Huan Daoming, Hu Xueyu, Shi Nai, Xie Yun, Li Xinyu, Xia Changrong, Peng Ranran, Lu Yalin
CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, 96 Jinzhai Road, Hefei, 230026, Anhui, P. R. China.
Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, No. 96 Jinzhai Road, Hefei, Anhui Province, 230026, P. R. China.
ChemSusChem. 2021 Sep 20;14(18):3876-3886. doi: 10.1002/cssc.202101100. Epub 2021 Aug 1.
Improving proton conduction in cathodes is regarded as one of the most effective methods to accelerate the sluggish proton-involved oxygen reduction reaction (P-ORR) for proton-conducting solid oxide fuel cells (P-SOFCs). In this work, K dopant was used to improve the proton uptake and migration ability of SrCo Nb O (SCN). K -doped SCN (KSCN) demonstrated great potential to be a promising cathode for P-SOFCs. Density functional theory calculations suggested that doping with K led to more oxygen vacancies and more negative values of hydration enthalpy, which was helpful for the improvement of proton concentration. Importantly, the proton migration barriers could be depressed, benefiting proton conduction. Electrochemical investigations signified that the cell using KSCN cathode had a peak power density of 967 mW cm at 700 °C, about 54.1 % higher than that using a SCN cathode. This research highlights the K -doping strategy to improve electrochemical performance of cathodes for P-SOFCs.
提高阴极中的质子传导被认为是加速质子传导固体氧化物燃料电池（P-SOFC）中缓慢的质子参与氧还原反应（P-ORR）的最有效方法之一。在这项工作中，使用钾掺杂剂来提高SrCoNbO（SCN）的质子吸收和迁移能力。钾掺杂的SCN（KSCN）显示出成为P-SOFC有前景的阴极的巨大潜力。密度泛函理论计算表明，钾掺杂导致更多的氧空位和更负的水合焓值，这有助于提高质子浓度。重要的是，质子迁移势垒可以降低，有利于质子传导。电化学研究表明，使用KSCN阴极的电池在700°C时的峰值功率密度为967 mW cm，比使用SCN阴极的电池高约54.1％。这项研究突出了钾掺杂策略对改善P-SOFC阴极电化学性能的作用。
