A detailed analysis of thermal and chemical compatibility of cathode materials for BaCeO3 and BaZrO3-based electrolytes for solid oxide fuel cell application

Abstract

The identification of suitable cathode materials, which can be successfully used in unit SOFCs based on proton-conducting electrolytes during long-term stability and thermal cycling measurements is investigated in the present work. To achieve this aim, a wide variety of materials were synthesized and their thermal and chemical compatibilities toward BaCe0.8Y0.2O3-δ and BaZr0.8Y0.2O3-δ are verified by means of detailed dilatometry and XRD analysis of calcined electrode/electrolyte mixtures, respectively. It is found that most of the studied cathodes are characterized by significant thermal expansion along with the tangible chemical one. Moreover, some of them react to a different degree with selected electrolytes. It is also found that, LaNi0.6Fe0.4O3-δ and La2NiO4+δ oxides can be considered as suitable cathode materials for BaCe0.8Y0.2O3-δ and BaZr0.8Y0.2O3-δ protonconducting electrolytes. Moreover, layered Y0.8Ca0.2BaCo4O7+δ cobaltite also possesses the required thermal properties and acceptable compatibility with BaZr0.8Y0.2O3-δ material.