Core-shell structured Fe@Ni aerogels as efficient bifunctional electrocatalysts for OER and MOR

The development of bifunctional non-noble metal electrocatalysts with high activity and stability remains a significant challenge. In this work, Fe@Ni aerogels with core-shell structure were synthesized by sol-gel method. The unique network-like architecture and amorphous core-shell structures of Fe@Ni aerogels provide abundant defects and unsaturated sites. Moreover, the tunable surface electronic structure enhances the availability of active catalytic sites, resulting in outstanding catalytic performance for both the oxygen evolution reaction (OER) and methanol oxidation reaction (MOR). For OER, the FeNi 2 aerogel requires only an overpotential of 215 mV to achieve a current density of 10 mA cm −2 , along with a low Tafel slope of 31.7 mV dec −1 and excellent stability. For MOR, its specific and mass activities were as high as 213.6 mA cm −2 and 106.8 A g −1 , respectively. In addition, this study also elucidated the mechanism of the excellent bifunctional catalytic activity of Fe@Ni core-shell aerogels, which provides a new idea for the development of other high-activity non-precious metal electrocatalysts. • Fe@Ni aerogels with a core-shell structure were synthesized in one step. • The core-shell structure enhances its geometric and electronic properties. • The aerogel demonstrates exceptional catalytic performance in OER and MOR.