Vanadium Doped Nickel Phosphide Nanosheets Self‐Assembled Microspheres as a High‐Efficiency Oxygen Evolution Catalyst

Abstract Recently, much attention has been paid to the low‐cost, high‐efficiency and stable non‐precious metal catalysts for oxygen evolution reaction (OER). In this work, vanadium (V)‐doped nickel phosphide (Ni 2 P) nanosheets self‐assembled microspheres supported on nickel foam (Ni 1 V 1 P NSs/NF) were synthesized as a novel OER catalyst by combined processes of hydrothermal method and low‐temperature phosphorization. The synthesized Ni 1 V 1 P NSs/NF material shows excellent catalytic activity due to its interconnected three‐dimensional (3D) structure and synergistic effect between nickel and vanadium. When used as a catalyst electrode for OER, the synthesized Ni 1 V 1 P NSs/NF exhibits excellent electrocatalytic activity, reaching a current density of 50 mA cm −2 at the low overpotential of 250 mV in 1.0 M KOH. This material also shows superior electrochemical stability with negligible decay of the activity after continual measurement for 15 h at 50 and 100 mA cm −2 in 1.0 M KOH, respectively. This work provides a valuable method to synthesize efficient OER catalysts by doping valence‐variable metal ions and designing distinctive 3D structure.