物理化学学报 >> 2013, Vol. 29 >> Issue (02): 311-318.doi: 10.3866/PKU.WHXB201212062

电化学和新能源 上一篇    下一篇

LaAlO3基电解质与阳极材料的化学相容性及电化学性能

覃国恒, 黄晓巍, 胡智   

  1. 福州大学材料科学与工程学院, 福州 350108
  • 收稿日期:2012-09-17 修回日期:2012-12-05 发布日期:2013-01-14
  • 通讯作者: 黄晓巍 E-mail:xwhuang@fzu.edu.cn
  • 基金资助:

    福建省自然科学基金(2008J0146)资助项目

Chemical Compatibility and Electrochemical Performance between LaAlO3-Based Electrolyte and Selected Anode Materials

QIN Guo-Heng, HUANG Xiao-Wei, HU Zhi   

  1. College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, P.R. China
  • Received:2012-09-17 Revised:2012-12-05 Published:2013-01-14
  • Supported by:

    The project was supported by the Natural Science Foundation of Fujian Province, China (2008J0146).

摘要:

采用甘氨酸-硝酸盐法(GNP)合成La0.90Sr0.10Al0.97Mg0.03O3-δ (LSAM)粉体, 成型后经1500 °C、5 h 烧结的样品, 900 °C时其电导率为1.11×10-2 S·cm-1. 利用X射线衍射(XRD)、扫描电镜/X 射线能谱分析(SEM/EDX)和交流阻抗技术等表征手段研究NiO-Ce0.9Gd0.1O1.95 (Ni-GDC)、Sr0.88Y0.08TiO3 (SYT)和La0.75Sr0.25Cr0.5Mn0.5O3(LSCM)三种阳极材料与LSAM电解质的化学相容性. 结果表明, SYT 和LSCM与LSAM的化学相容性欠佳,SYT中的Sr2+和Ti4+向LSAM晶格的扩散明显, LSCM中的Mn3+和Cr3+向LSAM晶格的扩散显著; 而Ni-GDC与LSAM具有良好的化学相容性, 在1300 °C下两材料间阳离子的相互扩散作用极小. 800 °C时Ni-GDC的比表面极化电阻(RASP)值为5.12 Ω·cm2. LSAM 电解质(厚度为550 μm)支撑的Ni-GDC/GDC/LSAM/GDC/LSF(La0.75Sr0.25FeO3)单电池, 在800 °C时电池的开路电压为0.925 V, 最大功率密度为19.5 mW·cm-2.

关键词: LaAlO3基电解质, 化学相容性, 比表面极化电阻, 固体氧化物燃料电池

Abstract:

Powders of La0.90Sr0.10Al0.97Mg0.03O3-δ (LSAM) were synthesized by the glycine-nitrate process, and then sintered at 1500 °C for 5 h. Impedance spectroscopy at 900 °C in air revealed that the conductivity of LSAM was 1.11×10-2 S·cm-1. The chemical compatibility of LSAM with anode materials NiO-Ce0.9Gd0.1O1.95 (Ni-GDC), Sr0.88Y0.08TiO3 (SYT) and La0.75Sr0.25Cr0.5Mn0.5O3 (LSCM) was characterized by X-ray diffraction, scanning electron microscopy with energy-dispersive X-ray spectroscopy and AC impedance spectroscopy. The results indicated that SYT and LSCM had poor chemical compatibility with LSAM because Sr2+, Ti4+, Mn3+, and Cr3+ diffused readily into the LSAM lattice. The interdiffusion of cations between LSAM and Ni- GDC at 1300 °C was limited, implying excellent chemical compatibility. The electrochemical performance of symmetrical cells of the anode materials was measured under hydrogen atmosphere. The area-specific polarization resistance of Ni-GDC was 5.12 Ω·cm2 at 800 ° C. An open-circuit voltage of 0.925 V and a power density of 19.5 mW·cm-2 were obtained at 800 °C for a 550 μm thick LSAM electrolyte-supported single cell (Ni-GDC/GDC/LSAM/GDC/La0.75Sr0.25FeO3).

Key words: LaAlO3-based electrolyte, Chemical compatibility, Area-specific polarisation resistance, Solid oxide fuel cell