Heterointerface engineering of FeNiP-CeO2/NF for efficient and durable oxygen evolution at high current densities

FeNiP-CeO 2 /NF heterostructure is designed for efficient oxygen evolution reaction. • Superior OER activity: 231, 304, 390 mV at 100, 500, 1000 mA·cm −2 . • Performance optimized by heterostructure design and interfacial synergistic effect. • The catalyst exhibits outstanding long-term stability of 200 h at 500 mA·cm −2 . Developing efficient and durable non-noble-metal electrocatalysts for the oxygen evolution reaction under industrially relevant conditions remains a significant challenge. Herein, a heterostructured FeNiP-CeO 2 /NF electrocatalyst was rationally designed and synthesized via a two-step hydrothermal–phosphidation strategy. The resulting catalyst features hierarchically assembled FeNiP nanosheets intimately coupled with oxygen-vacancy-rich CeO 2 nanoparticles, forming abundant heterointerfaces. Benefiting from the synergistic interaction between bimetallic Fe–Ni phosphide active sites and CeO 2 -induced interfacial charge redistribution, FeNiP-CeO 2 /NF exhibits markedly enhanced OER activity in alkaline media, delivering low overpotentials of 231, 304, and 390 mV at current densities of 100, 500, and 1000 mA cm −2 , respectively. In addition, the catalyst demonstrates excellent long-term durability, maintaining stable operation for 200 h at 500 mA cm −2 with a Faradaic efficiency of 99.3%. This work demonstrates that rational heterointerface engineering combined with hierarchical structural design is an effective strategy for constructing highly active and robust OER electrocatalysts, highlighting the promising potential of FeNiP-CeO 2 /NF for industrial water electrolysis applications. Download: Download high-res image (256KB) Download: Download full-size image