High performance proton-conducting solid oxide fuel cells with a stable Sm_(0.5)Sr_(0.5)Co_(3-δ)-Ce_(0.8)Sm_(0.2)O_(2-δ) composite cathode

摘要

A Sm_(0.5)Sr_(0.5)Co_(3-δ)-Ce_(0.8)Sm_(0.2)O_(2-δ) (SSC-SDC) composite is employed as a cathode for proton-conducting solid oxide fuel cells (H-SOFCs). BaZr_(0.1)Ce_(0.7)Y_(0.2)O_(3-δ) (BZCY) is used as the electrolyte, and the system exhibits a relatively high performance. An extremely low electrode polarization resistance of 0.066 Ω cm~2 is achieved at 700℃. The maximum power densities are: 665,504,344, 214, and 118m W cm~(-2) at 700, 650,600,550, and 500 ℃, respectively. Moreover, the SSC-SDC cathode shows an essentially stable performance for 25 h at 600 ℃ with a constant output voltage of 0.5 V. This excellent performance implies that SSC-SDC, which is a typical cathode material for SOFCs based on oxide ionic conductor, is also a promising alternative cathode for H-SOFCs.