High-performance direct carbon dioxide-methane solid oxide fuel cell with a structure-engineered double-layer anode.

Reduced La 0.6 Sr 0.2 Cr 0.85 Ni 0.15 O 3 (LSCrN) contains exsolved Ni nanoparticles (LSCrN@Ni) and abundant oxygen vacancies. Thus, it is an excellent catalyst for CO 2 dry reforming of CH 4. To use CH 4 directly in solid oxide fuel cells, Ni–Ce 0.9 Gd 0.1 O 1.95 (GDC) anode-supported cells are fabricated with and without a layer of LSCrN@Ni-20 wt% GDC on top of the anode, which are defined as double anode supported cell (DASC) and conventional anode supported cell (CASC), respectively. They are investigated comparatively by X-ray diffraction, thermal expansion, thermogravimetry, scanning electron microscopy, and electrochemical performance measurement in H 2 and 50%CO 2 –50%CH 4 fuels. Both CASC and DASC demonstrate similarly high performance with H 2 fuel, the maximum power density is 856 and 822 mW cm−2 at 750 °C, respectively. When 50%CO 2 –50%CH 4 is used, DASC outperforms CASC significantly, showing a maximum power density of 758 mW cm−2 and an on-cell CH 4 conversion of 85.5% at 750 °C. Also, DASC demonstrates a stable performance, and the cell voltage and CH 4 conversion remain unchanged at 0.65 V and 84% without detectable carbon formation in the anode, while those of CASC decrease monotonously from the beginning with observable carbon formation during a test of 36 h under 400 mA cm−2 at 750 °C. Image 1 • On-cell DRC is achieved by adding an LSCrN@Ni-GDC layer on the top of Ni-GDC anode. • LSCrN@Ni-GDC catalyst is more active and stable than Ni-GDC for DRC reaction. • Single cell with LSCrN@Ni-GDC fueled with CO 2 –CH 4 outperforms the conventional one. [ABSTRACT FROM AUTHOR]