Synergistic dealloying and heterojunction construction on Ni-Fe-P ribbons for enhanced oxygen evolution

A synergistic dealloying and heterojunction construction strategy is developed on crystalline Ni–Fe–P ribbons. • The strong heterointerface enables efficient interfacial charge transfer and exposes abundant active sites for OER. • The electronic structure and surface reconstruction of the ribbon are modulated via LDH-induced interfacial coupling. Ni-Fe based ribbons are promising self-supporting oxygen evolution reaction (OER) electrocatalysts due to their low cost, good conductivity, and high intrinsic activity. However, pristine ribbons exhibit poor OER performance because their smooth, non-porous surface leads to limited active sites and their sluggish surface reconstruction lowers intrinsic activity. Dealloying can create nanoporous structures, but this single strategy suffers from a trade-off between mechanical integrity and active area, as well as a depth limitation of the porous layer (~500 nm). Herein, we report a synergistic strategy combining mild dealloying pretreatment with in situ growth of NiFe-LDH on Ni-Fe-P ribbons. Moderate dealloying preserves mechanical robustness while providing a nanoporous anchoring layer. Subsequent growth of NiFe layered double hydroxide (NiFe-LDH) nanosheets compensates for the limited active area, builds a deep three-dimensional catalytic network beyond the dealloying-limited depth, and forms a strong heterointerface that facilitates charge transfer. The optimized Ni-Fe-P/LDH electrode achieves a low overpotential of 245 mV at 20 mA cm −2 , substantially outperforming the pristine ribbon (353 mV) and the solely dealloyed ribbon (267 mV), and maintains stable operation for over 100 h at 10 mA cm −2 and 50 h at 500 mA cm −2 . This work demonstrates the feasibility of combining dealloying and heterojunction engineering for high-performance self-supporting OER electrocatalysts.