High performance cobalt-free Cu1.4Mn1.6O4 spinel oxide as an intermediate temperature solid oxide fuel cell cathode

In this work Cu 1.4 Mn 1.6 O 4 (CMO) spinel oxide is prepared and evaluated as a novel cobalt-free cathode for intermediate temperature solid oxide fuel cells (IT-SOFCs). Single phase CMO powder with cubic structure is identified using XRD . XPS results confirm that mixed Cu + /Cu 2+ and Mn 3+ /Mn 4+ couples exist in the CMO sample, and a maximum conductivity of 78 S cm −1 is achieved at 800 °C. Meanwhile, CMO oxide shows good thermal and chemical compatibility with a 10 mol% Sc 2 O 3 stabilized ZrO 2 (ScSZ) electrolyte material. Impedance spectroscopy measurements reveals that CMO exhibits a low polarization resistance of 0.143 Ω cm 2 at 800 °C. Furthermore, a Ni-ScSZ/ScSZ/CMO single cell demonstrates a maximum power density of 1076 mW cm −2 at 800 °C under H 2 (3% H 2 O) as the fuel and ambient air as the oxidant. These results indicate that Cu 1.4 Mn 1.6 O 4 is a superior and promising cathode material for IT-SOFCs.