Facile synthesis of nanosized nickel phosphides with controllable phase and morphology

Abstract

A solvothermal route was developed to synthesize nanosized nickel phosphides with controllable phase and morphology using non-toxic red phosphorus as the P³⁻ ion source. The crystal phases and morphologies of nickel phosphides were facilely controlled by adjusting the counter anions of nickel salts and the solvents without additional additives. Four nickel sources (NiCl₂·6H₂O, Ni(CH₃COO)₂·4H₂O, NiSO₄·6H₂O and Ni(NO₃)₂·6H₂O) and six solvents (H₂O, methanol, ethanol, glycol, glycerol and polyglycol) were applied in the synthesis. The obtained nickel phosphides were characterized by XRD, SEM and TEM. The results indicated that two pure phases of Ni₂P and Ni₁₂P₅ with different exposition of the crystal surface and varied micro-morphologies can be achieved in this system, thus providing a facile way to prepare nickel phosphides with controllable phases and morphologies.