Synthesis of high-quality Ni2P hollow sphere via a template-free surfactant-assisted solvothermal route

Ni2P uniform hollow nanospheres were prepared via a template-free surfactant-assisted solvothermal route using NiCl2·6H2O and elemental yellow phosphorus as starting materials and urea as pH regulator in a mixture solution of ethylene glycol (EG), ethanol and water. X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), transmission electronic microscopy (TEM), electron diffraction (ED), and scanning electron microscopy (SEM) studies show that the as-obtained nanocrystal is pure Ni2P with a hexagonal phase and the high-quality spheres are about 500 nm in diameter. The experimental results indicated that sodium dodecyl sulfate (SDS) and urea play an important role in controlling the formation of Ni2P hollow nanospheres. The possible growth mechanism is proposed.