Cobalt-free oxide Ba0.5Sr0.5Fe0.8Cu0.2O3−δ for proton-conducting solid oxide fuel cell cathode

A cobalt-free perovskite oxide Ba0.5Sr0.5Fe0.8Cu0.2O3−δ (BSFC) is employed as a cathode material for intermediate-temperature proton-conducting solid oxide fuel cells. Symmetrical electrochemical cell with the configuration of BSFC-BZCY/BZCY/BSFC-BZCY is applied for the impedance study. The single cell, consisting of BSFC-BZCY/BZCY/NiO-BZCY structure, is assembled and tested from 600 to 700 °C with humidified hydrogen (∼3% H2O) as the fuel and the static air as the oxidant. A maximum power density of 430 mW cm−2 is obtained at 700 °C for the single cell. Long-term stability of the BSFC-BZCY/BZCY/NiO-BZCY single cell at 600 °C for 40 h has also been studied. Preliminary results demonstrat that cobalt-free oxide BSFC is a very promising cathode for application in proton-conducting solid oxide fuel cells.