Direct ethanol solid oxide fuel cells integrated with internal reforming for renewable power generation

Solid oxide fuel cells (SOFCs) can directly convert bio-ethanol (a product of biomass process) into renewable power with high energy efficiency and low environmental impact, while it is still a challenge to achieve stable power generation because ethanol fuel readily causes carbon deposition over the state-of-the-art Ni-based anodes. This study has developed the anode supports integrated with internal reformers to convert ethanol into syngas, and the internal reformers were constructed by packing Ru-GDC nanofibrous catalysts within microchannels embedded in anode supports. The internal reforming increased the maximum power density (MPD) from 388.4 to 944.5 mW cm⁻² at 800 °C and a low ethanol concentration of 6.5%, which is the highest-recorded MPD of oxygen ion-conducting SOFCs using ethanol fuel. The MPD increased with operation temperature and ethanol concentration while high ethanol concentration reduced ethanol conversion and potentially promoted carbon deposition. Adding steam with ethanol like conventional ethanol-fueled SOFCs greatly decreased MPD due to fuel dilution and the reduced open circuit voltage. The direct ethanol SFOCs with internal reformers demonstrated stable power generation at a current density of 1.0 A cm⁻² for 236 h.