Controlled Synthesis of 3D Flower-like Ni 2 P Composed of Mesoporous Nanoplates for Overall Water Splitting.

Developing efficient non-noble metal and earth-abundant electrocatalysts with tunable microstructures for overall water splitting is critical to promote clean energy technologies for a hydrogen economy. Herein, novel three-dimensional (3D) flower-like Ni2 P composed of mesoporous nanoplates with controllable morphology and high surface area was prepared by a hydrothermal method and low-temperature phosphidation as efficient electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Compared with the urchin-like Nix Py , the 3D flower-like Ni2 P with a diameter of 5 μm presented an efficient and stable catalytic performance in 0.5 m H2 SO4 , with a small Tafel slope of 79 mV dec-1 and an overpotential of about 240 mV at a current density of 10 mA cm-2 with a mass loading density of 0.283 mg cm-2 . In addition, the catalyst also exhibited a remarkable performance for the OER in 1.0 m KOH electrolyte, with an overpotential of 320 mV to reach a current density of 10 mA cm-2 and a small Tafel slope of 72 mV dec-1 . The excellent catalytic performance of the as-prepared Ni2 P may be ascribed to its novel 3D morphology with unique mesoporous structure.