Core-Shell Structure of Ni

Hydrogen energy has attracted considerable attention due to its zero emissions and high conversion efficiency. However, the sluggish anodic kinetics in anion exchange membrane fuel cells (AEMFCs) necessitate the use of high-load platinum-group metal (PGM) catalysts, significantly increasing system cost. Herein, a nickel-based electrocatalyst of Ni17W3@W with a unique core-shell structure is reported, which exhibits outstanding intrinsic activity with an electrochemical surface area-normalized exchange current density of 0.072 mA cmNi -2. Compared to commercial Pt/C, Ni17W3@W also demonstrates superior CO tolerance and long-term operational stability. X-ray absorption spectroscopy and ultraviolet photoelectron spectroscopy reveal an increased valence state of Ni in Ni17W3@W, leading to a downshift of d-band center and a corresponding decrease in hydrogen binding energy. In situ surface enhanced infrared absorption spectroscopy confirms that the W shell optimizes the interfacial water structure, enhancing the hydrogen-bonding network and further promoting the hydrogen oxidation reaction. Moreover, the porous W shell serves as a protective barrier, effectively preventing oxidation of the Ni17W3 core and ensuring long-term catalyst durability. This work offers valuable insights for the rational design of high-performance non-PGM anode catalysts in AEMFCs.