Protonic ceramic fuel cells(PCFCs) are promising for efficient,clean energy conversion at low to intermediate temperatures,but the widely used BaZr_(0.1)-Ce_(0.7)Y_(0.1)Yb_(0.1)O_(3-δ)(BZCYYb) electrolyte has poor ch...Protonic ceramic fuel cells(PCFCs) are promising for efficient,clean energy conversion at low to intermediate temperatures,but the widely used BaZr_(0.1)-Ce_(0.7)Y_(0.1)Yb_(0.1)O_(3-δ)(BZCYYb) electrolyte has poor chemical stability in humid environments.Herein,we show that under oxygen reduction reaction(ORR) conditions,water accumulates at the BaGd_(0.8)La_(0.2)Co_(2)O_(6-δ)(BGLC)cathode-BZCYYb electrolyte interface,causing selective loss of B a cations and decomposition of BZCYYb electrolyte.The introduction of triply ion-electron conducting La_(2)Ce_(2)O_(7-δ)(LCeO) into the BGLC cathode expands its active reaction area,accelerates ORR kinetics,and suppresses water accumulation at the cathode-electrolyte interface and electrolyte decomposition.A single cell with the BGLC-LCeO composite cathode achieves a peak power density of 1.07 W cm^(-2)at 700℃,with no profound degradation at 0.5 A cm^(-2)over 100 h.These findings provide guidance for the development of high-performance,durable PCFCs.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.22279018 and 22005055)
文摘Protonic ceramic fuel cells(PCFCs) are promising for efficient,clean energy conversion at low to intermediate temperatures,but the widely used BaZr_(0.1)-Ce_(0.7)Y_(0.1)Yb_(0.1)O_(3-δ)(BZCYYb) electrolyte has poor chemical stability in humid environments.Herein,we show that under oxygen reduction reaction(ORR) conditions,water accumulates at the BaGd_(0.8)La_(0.2)Co_(2)O_(6-δ)(BGLC)cathode-BZCYYb electrolyte interface,causing selective loss of B a cations and decomposition of BZCYYb electrolyte.The introduction of triply ion-electron conducting La_(2)Ce_(2)O_(7-δ)(LCeO) into the BGLC cathode expands its active reaction area,accelerates ORR kinetics,and suppresses water accumulation at the cathode-electrolyte interface and electrolyte decomposition.A single cell with the BGLC-LCeO composite cathode achieves a peak power density of 1.07 W cm^(-2)at 700℃,with no profound degradation at 0.5 A cm^(-2)over 100 h.These findings provide guidance for the development of high-performance,durable PCFCs.
