Zhu Ziyi, Zhou Mingyang, Tan Kai, Fan Zidai, Cao Dan, Liu Zhijun, Chen Meilong, Chen Yu, Chen Min, Liu Jiang
Guangzhou Key Laboratory for Surface Chemistry of Energy Materials, New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
School of Materials Science and Engineering, Georgia Institute of Technology, 771 Ferst Drive, Atlanta, Georgia 30332-0245, United States.
ACS Appl Mater Interfaces. 2023 Mar 22;15(11):14457-14469. doi: 10.1021/acsami.3c00728. Epub 2023 Mar 9.
The solid oxide cell (SOC) based on a proton-conducting electrolyte is promising to play an important role in large-scale energy storage and hydrogen production. However, its development is hindered by performance degradation caused by the mismatch in thermal expansion coefficients (TECs) between the electrolyte and the oxygen electrode. Although there is work on reducing TECs of the oxygen electrode, it is difficult to find proper materials having a low TEC while maintaining a high performance. In this paper, we propose a new path to solve this problem: increasing the TEC of the electrolyte. We demonstrate that doping Fe into BaZrCeYYbO (BZCYYb) can increase the TEC from 10.3 × 10 K of BZCYYb to 13.4 × 10 K of BaZrCeFeYYbO (BZCYYbF). Fe doping also enhances the sinterability, electrochemical performance, and stability of the electrolyte. Meanwhile, we find that doping Fe into the oxygen electrode material PrNiCoO (PNC) decreases the TEC from 19.2 × 10 K of PNC to 17.4 × 10 K of PrNiCoFeO (PNCF). The improved stability of the SOC with the BZCYYbF electrolyte and the PNCF oxygen electrode is verified for steam electrolysis under a high steam partial pressure, 50%. Such a cell operates stably at a current density of 1.76 A cm under 1.30 V and 700 °C for 150 h.
基于质子传导电解质的固体氧化物电池（SOC）有望在大规模储能和制氢方面发挥重要作用。然而，其发展受到电解质与氧电极之间热膨胀系数（TEC）不匹配导致的性能退化的阻碍。尽管有关于降低氧电极TEC的工作，但很难找到在保持高性能的同时具有低TEC的合适材料。在本文中，我们提出了一条解决此问题的新途径：提高电解质的TEC。我们证明，将Fe掺杂到BaZrCeYYbO（BZCYYb）中可使TEC从BZCYYb的10.3×10⁻⁶K增加到BaZrCeFeYYbO（BZCYYbF）的13.4×10⁻⁶K。Fe掺杂还提高了电解质的烧结性、电化学性能和稳定性。同时，我们发现将Fe掺杂到氧电极材料PrNiCoO（PNC）中可使TEC从PNC的19.2×10⁻⁶K降低到PrNiCoFeO（PNCF）的17.4×10⁻⁶K。在50%的高蒸汽分压下对蒸汽电解验证了采用BZCYYbF电解质和PNCF氧电极的SOC的稳定性得到改善。这样的电池在1.30V和700℃下以1.76A/cm²的电流密度稳定运行150小时。
