Iron-Doped Nickel Phosphide Nanosheet Arrays: An Efficient Bifunctional Electrocatalyst for Water Splitting

Exploring
efficient and earth-abundant electrocatalysts for water splitting
is crucial for various renewable energy technologies. In this work,
iron (Fe)-doped nickel phosphide (Ni2P) nanosheet arrays
supported on nickel foam (Ni1.85Fe0.15P NSAs/NF)
are fabricated through a facile hydrothermal method, followed by phosphorization.
The electrochemical analysis demonstrates that the Ni1.85Fe0.15P NSAs/NF electrode possesses high electrocatalytic
activity for water splitting. In 1.0 M KOH, the Ni1.85Fe0.15P NSAs/NF electrode only needs overpotentials of 106 mV
at 10 mA cm–2 and 270 mV at 20 mA cm–2 to drive the hydrogen evolution reaction (HER) and oxygen evolution
reaction (OER), respectively. Furthermore, the assembled two-electrode
(Ni1.85Fe0.15P NSAs/NF∥Ni1.85Fe0.15P NSAs/NF) alkaline water electrolyzer can produce
a current density of 10 mA cm–2 at 1.61 V. Remarkably,
it can maintain stable electrolysis over 20 h. Thus, this work undoubtedly
offers a promising electrocatalyst for water splitting.