Enhanced performance of symmetrical solid oxide fuel cells using a doped ceria buffer layer

Abstract

Enhanced performance of symmetrical solid oxide fuel cell (SSOFC) is reported by using a doped ceria buffer layer, which can solve the issues during the operation of traditional solid oxide fuel cells, such as carbon deposition and sulfur poisoning. In this work, cobalt-free perovskite oxide La0.8Sr0.2FeO3-δ (LSF) is applied as a novel stable electrode material for symmetrical solid oxide fuel cell. The electrical conductivities of LSF are 141.1Scm−1 and 0.138Scm−1 in air and humidified H2 (3% H2O) at 800°C, respectively. Gadolinium doped ceria (GDC) buffer layer is fabricated by screen printing onto the YSZ electrolyte, which dramatically enhances the electrochemical performance by more than 90 percent at 700°C. The improvement of SSOFC performance is attributed to the elimination of reactivity and the optimization of interface between YSZ electrolyte and LSF electrode. These results demonstrate that the doped ceria buffer layer provides a highly repeatable route for further improving the performance of YSZ-based SSOFC, with potentially important implications for developing cost-effective SSOFCs with huge application opportunities.