Scholarlink

<p>Composite cathodes based on La<sub>0.7</sub>Sr<sub>0.3</sub>MnO<sub>3</sub> (LSM) and 8&#xa0;mol% yttria-stabilized zirconia (8YSZ) are widely adopted in solid oxide fuel cells (SOFCs) due to their thermal compatibility and electrochemical stability. However, critical questions remain regarding the interplay between these phases and their impact on ionic transport. In this study, LSM-8YSZ composites with varying volumetric ratios (10–90 vol% LSM) were systematically investigated to elucidate the structural, thermal, and electrical consequences of phase interactions. Contrary to expectations, no resistive zirconate phases were detected via X-ray diffraction in samples sintered at 1400&#xa0;°C. Electrochemical impedance spectroscopy evidenced a severe degradation of ionic transport properties in LSM-8YSZ composites, characterized by a 35-fold reduction in grain conductivity and an increase of more than 70-fold in grain-boundary resistance relative to pure 8YSZ. The combined SEM and EIS analyses indicate that the dominant degradation mechanism can be strongly associated with microstructural changes, particularly the increase in porosity and the disruption of the percolative network of 8YSZ grains in the composite. These effects markedly compromise the continuity of oxygen-ion transport pathways and are therefore considered the primary cause of the pronounced loss in electrochemical functionality of 8YSZ.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Effects of the La0.7Sr0.3MnO3 and 8 mol% yttria-stabilized zirconia phases on the conductivity and stability of composite cathodes

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年7月7日

查看全文
  • Thiago Dias,
  • Fábio C. Antunes,
  • João P. J. de Oliveira,
  • João Pedro Aguiar dos Santos,
  • Danilo A. Dantas,
  • Julian D. Hunt,
  • Hudson Zanin,
  • Gustavo Doubek

摘要

Composite cathodes based on La0.7Sr0.3MnO3 (LSM) and 8 mol% yttria-stabilized zirconia (8YSZ) are widely adopted in solid oxide fuel cells (SOFCs) due to their thermal compatibility and electrochemical stability. However, critical questions remain regarding the interplay between these phases and their impact on ionic transport. In this study, LSM-8YSZ composites with varying volumetric ratios (10–90 vol% LSM) were systematically investigated to elucidate the structural, thermal, and electrical consequences of phase interactions. Contrary to expectations, no resistive zirconate phases were detected via X-ray diffraction in samples sintered at 1400 °C. Electrochemical impedance spectroscopy evidenced a severe degradation of ionic transport properties in LSM-8YSZ composites, characterized by a 35-fold reduction in grain conductivity and an increase of more than 70-fold in grain-boundary resistance relative to pure 8YSZ. The combined SEM and EIS analyses indicate that the dominant degradation mechanism can be strongly associated with microstructural changes, particularly the increase in porosity and the disruption of the percolative network of 8YSZ grains in the composite. These effects markedly compromise the continuity of oxygen-ion transport pathways and are therefore considered the primary cause of the pronounced loss in electrochemical functionality of 8YSZ.