Nitrogen-doped cerium-iron phosphide as an ultra-efficient Ru-free electrocatalyst for oxygen evolution reaction

Designing nonprecious metal-based heteroatom-doped electrocatalysts with low overpotential for efficient hydrogen production via oxygen evolution reactions presents significant challenges. We fabricated and carbonized an N-doped bimetallic phosphide (CeFeP) in this study. Scanning electron microscopy and transmission electron microscopy analyses revealed the formation of a uniform spherical nanoparticle morphology, while structural changes were evidenced in the carbonization step at temperatures of 300 and 700 ℃ by XRD analysis. The synthesized materials were then coated onto carbon paper electrodes in a basic medium, and their performance in the oxygen evolution reaction was evaluated. The results show that the N-doped bimetallic phosphide material carbonized at 700 ℃ has enhanced catalytic activity, as indicated by its low overpotential of 155 mV and Tafel slope of 57 mV/dec, respectively, for a standard current density of 10 mA/cm2. The catalytic performance of the N-doped CeFeP sample was significantly higher than that of undoped CeFeP and the single metal phosphide, thereby indicating it has significant potential for practical applications.