Direct carbon dioxide-methane solid oxide fuel cells combined with in-situ exsolution perovskite La0.75Sr0.25Cr0.5Fe0.4Cu0.1O3-δ-based dry reforming catalysts

Abstract

In response to greenhouse effect and energy crisis, the clean and efficient use of CH4 and CO2 resources has become increasingly attractive. Against this background, solid oxide fuel cells (SOFCs) have become one of the research hotspots due to the possibility of utilizing methane and carbon dioxide for the conversion into syngas (H2 and CO) for efficient direct power generation. In this study, we propose to dope Cu into La0.75Sr0.25Cr0.5Fe0.5O3-δ to enhance the catalytic activity for direct carbon dioxide-methane dry reforming reactions. In wet hydrogen conditions, Fe nanoparticles can effectively exsolve from La0.75Sr0.25Cr0.5Fe0.4Cu0.1O3-δ (LSCFC), which is beneficial for the dry reforming reaction of methane. With the LSCFC-Ce0.9Gd0.1O2-δ (LSCFC-GDC) composite reforming layer, the anode-supported single cells exhibited remarkable electrochemical performance. When fueled with both H2 and CH4–CO2, the maximum power densities achieved 608.3 and 497.1 mW cm−2 at 800 °C, with corresponding polarization resistance values of 0.35 and 1.11 Ω cm2, respectively. Furthermore, the single cells with LSCFC-GDC reforming layer showed excellent carbon tolerance, maintaining stable performance for 120 h using 50%CH4–50%CO2. Our results demonstrate the use of dry reforming catalysts in SOFCs is effective in both enhancing CH4–CO2 reforming efficiency and maintaining carbon tolerance.