Enhanced Compatibility and Activity of High-entropy Double Perovskite Cathode Material for IT-SOFC

Intermediate-temperature solid oxide fuel cell (IT-SOFC) is promising for carbon neutrality, but its cathode is limited by the contradiction between thermal compatibility and catalytic activity. Herein, we propose a high-entropy double perovskite cathode material, GdBa(Fe0.2Mn0.2Co0.2Ni0.2Cu0.2)(2)O5+delta (HE-GBO) with improved compatibility and activity, in view of the high-entropy strategy by multi-elemental coupling, which possesses double perovskite structure and excellent chemical compatibility with state-of-the-art Gd0.1Ce0.9O2-delta (GDC). The polarization resistance (R-p) of the symmetrical cells with HE-GBO cathode is 1.68 ohm center dot cm(2) at 800 degrees C, and the corresponding R-p of HE-GBO-GDC (mass ratio 7:3) composite cathode can be greatly reduced (0.23 ohm center dot cm(2) at 800 degrees C) by introducing GDC. Dendritic microchannels anode-supported single cells with HE-GBO and HE-GBO-GDC cathodes realize maximum power densities of 972.12 and 1057.06 mW/cm(2) at 800 degrees C, respectively, indicating that cell performance can be enhanced by high-entropy cathodes. The results demonstrate that high-entropy double perovskite cathode material HE-GBO has a high potantial to solve the conflict problem of thermal compatibility and catalytic activity in IT-SOFCs.