H2O-gasification direct carbon solid oxide fuel cells utilizing biochar as fuel for high-performance electricity generation

Abstract

H 2 O-gasification direct carbon solid oxide fuel cells (DC-SOFCs) show promise for operation at reduced temperatures. In this study, Camellia oleifera shell biochar is utilized in H 2 O-gasification DC-SOFCs to improve cell performance and broaden fuel applicability. The biochar contains inherent catalysts for the steam-carbon gasification, while its hydrogen content contributes to in situ generation of steam. The cells, fabricated with an LSGM electrolyte-supported structure, are evaluated at 700 °C. The cell at the optimal H 2 O/C ratio of 7.5% achieves a peak power density of 189 mW cm −2 , significantly superior to the conventional cell (78 mW cm −2 ) and approaching the H 2 -fueled SOFC (216 mW cm −2 ). Moreover, the cell exhibits improved discharge stability with a lifetime of 11.33 h and a fuel utilization of 17.6%. These findings demonstrate the feasibility of biochar fuel for H 2 O-gasification DC-SOFCs, offering a promising strategy for high-performance cell development and green biomass utilization.