High performance Mn1.3Co1.3Cu0.4O4 spinel based composite cathodes for intermediate temperature solid oxide fuel cells†
Herein, we developed a Mn1.3Co1.3Cu0.4O4 (MCCO) spinel for use as a new ORR catalyst for intermediate temperature solid oxide fuel cell (SOFC) applications. The addition of Cu to the (Mn,Co)3O4 spinel effectively promoted the oxidation states of Mn ions, which were mostly positioned at octahedral sites. This effect facilitated small polaron hopping with a narrow band gap, resulting in high electrical conductivity of MCCO. An SOFC employing the MCCO–Sc0.1Zr0.89Ce0.01O1.95 composite cathode yielded extraordinarily high power-output values of 1.92 and 1.38 W cm−2, at 800 and 700 °C, respectively. To the best of our knowledge, this result indicates the best performance among all SOFCs with any spinel-based cathodes to date.