Anode Containing Nickel and Molybdenum Oxide Catalysts for Ethanol Reforming in Solid Oxide Fuel Cells

Resumo

This work presents a catalytic anodic layer based on nickel and molybdenum oxides (NiO/MoO_x) for
ethanol reforming in solid oxide fuel cells (SOFCs). Flat disc-shaped cells (50 mm diameter, 0.4 mm
thick) were fabricated, incorporating a cathode, electrolyte, and a catalytic anode containing both nickel
and molybdenum oxide. Unlike most studies focusing on button cells with active areas of 0.5–1.0 cm²,
this work explores a larger active area of 9.62 cm², advancing efforts toward scalable SOFC designs.
Electrochemical performance was assessed through impedance spectroscopy and voltammetry. At
740 °C using hydrogen, the cell without MoOx showed a polarization resistance of 0.43 Ω cm², a current
density of 0.67 A cm for the maximum peak power density of 345.6 mW cm^–2. With MoO_x, polarization
resistance dropped to 0.33 Ω cm², current density increased to 0.79 A cm^–2 for the maximum power
density of 378.4 mW cm^–2. Using an ethanol-water (1:3) mixture, the cell with MoO_x achieved superior
performance: 0.23 Ω cm² polarization resistance, 0.97 A cm^–2 current density for the maximum power
density of 404.4 mW cm^–2 —versus 0.28 Ω cm², 0.62 A cm^–2 for 300.4 mW cm^–2 without the catalyst.
These results highlight the effective catalytic role of MoO_x in enhancing SOFC efficiency during direct
ethanol reforming.