Electronic Properties Modulation of NiFe-based Nanoalloy by Introducing Cu and P for Faster Oxygen Evolution Reaction Kinetics

NiFe-based structures are well known for their high Oxygen Evolution Reaction (OER) activity. But, over time, because of Fe dissolution from these structures, activity and stability decreases gradually. In this work, we have presented a one-pot facile way to introduce Cu and P centres in a NiFe-based nanoalloy to get novel transition metal-based hierarchical nanostructures that show enhanced catalytic activity as well as remarkable stability. As evident from electron micrographs (EMs) followed by Electrochemically Active Surface Area (EASA) calculations, the introduction of Cu and P increases the active surface area compared to NiFe nanoalloy. Understanding the relationship between the local geometry of catalytically active sites and the OER activity is an invincible step for more advanced material fabrication. By studying X-ray Photoelectron Spectroscopy (XPS), X-ray Absorption Near Edge Structure (XANES), and Extended X-ray Absorption Fine Structure (EXAFS) of these materials, we understood the modulation of electronic properties of NiFe-based nanoalloy by introducing Cu and P centres within it. This electronic modulation of the newly developed hierarchical structures results in faster OER kinetics with an overpotential of 213 mV at a current density of 10 mA/cm2. Moreover, electrochemical studies clearly justify that all metal centres (i.e., Ni, Fe, and Cu) are positively participating in the OER kinetics.