Ni2P/NiCo2S4/NF nanocomposite as an anode catalyst for constructing urea fuel cells.

Ni-based catalysts have been considered as an efficient anode material for urea fuel cells due to their low cost and high activity in alkaline media. Ni₂P/NiCo₂S₄ catalyst grown on nickel foam was synthesized by hydrothermal synthesis and solid phosphating. The cathode material Pt/C was prepared using the drop-coating method, which has good oxygen reduction reaction (ORR) activity. H-type urea/O₂ fuel cell was assembled and showed high energy density in alkaline solution at room temperature. X-Ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDS) were employed to characterize the Ni₂P/NiCo₂S₄/NF catalyst. Results confirmed the formation of 3D flower-like microspheres from Ni₂P/NiCo₂S₄/NF catalyst nanosheets. Electrochemical testing results indicated that the Ni₂P/NiCo₂S₄/NF catalyst-decorated electrode can effectively promote urea oxidation and plays a leading role in improving the performance of fuel cells in 1 M KOH + 0.33 M urea. The H-type urea/O₂ fuel cell possesses a high power density of 0.42 mW cm⁻² at a cell potential of 0.45 V. To summarize, this study introduces a cheap but efficient electrode material as an anode catalyst for constructing urea fuel cells. [ABSTRACT FROM AUTHOR]