Performance improvement of direct internal reforming solid oxide fuel cell fuelled by H₂S-contaminated biogas with paper-structured catalyst technology

Direct internal reforming (DIR) operation of a solid oxide fuel cell (SOFC) is a very attractive concept for downsizing and cost reduction of SOFC systems. This study aimed to develop stable operation of a DIR-SOFC fuelled by biogas. The current-voltage (I-V) curves of 2 × 2 cm² planar SOFCs (anode- and electrolyte-supported cells, ASC and ESC, respectively.) were measured at 800 °C in the direct feed of a simulated biogas mixture (CH₄/CO₂ = 1), and the flexible structured catalyst material (paper-structured catalyst (PSC)) was applied on the anode material for performance enhancement. By applying a hydrotalcite (HT)-dispersed PSC (HT-PSC), the sulfur tolerance of the SOFC in the DIR operation was remarkably improved. By the effect of the HT-PSC, for both ASC and ESC, a stable cell voltage higher than 800 mV was obtained over 200 h at 0.2 A cm⁻² in the direct feed of simulated biogas under 5 ppm H₂S poisoning.