Tuning La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ perovskite cathode as functional electrolytes for advanced low-temperature SOFCs

The ionic electrolyte and compatible cathode are major challenges to develop advanced low temperature solid oxide fuel cells (LT-SOFCs). Perovskite La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (LSCF) has considered as desired SOFC cathodes due to its unique advantages including high mixed electronic and ionic conductivity and excellent catalytic activity for oxygen reduction reaction. Our present work demonstrates the first application of LSCF tuned as functional electrolyte through composing with sodium carbonate. The mixed ionic and electronic conductor (MIEC)/carbonate LSCF/Na₂CO₃ nanocomposites can make use of the intrinsic high ionic conductivity of LSCF, and extend the three phase electrocatalytic reaction region into the electrolyte region along with suppress its electronic contribution, ultimately tuned as functional electrolyte material. Through optimizing Na₂CO₃ content, the novel LSCF/Na₂CO₃ nanocomposite gives rise to an superior fuel cell performance of 700 mW/cm² at 550 °C. This work has demonstrated a new approach to develop electrolyte materials tuned from MIEC for advanced LT-SOFCs for next-generation.