An efficient method for the synthesis of nickel phosphide nanocrystals via thermal decomposition of single-source precursors

Abstract

An efficient method was developed for the synthesis of nickel phosphide nanocrystals (NCs) via thermal decomposition of bis(triphenylphosphine)nickel dichloride (BTND) precursor in the presence of oleylamine (OAm) for the first time. The effect of synthetic conditions such as reaction temperature, reaction time and OAm quantity on the size and phase of the as-synthesized nickel phosphide NCs was discussed. The structure and morphology were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and N₂ adsorption–desorption measurements. The results showed that the size of Ni₂P NCs can be controlled by increasing reaction temperature and OAm quantity. The phase of nickel phosphide NCs can be controlled by changing the reaction time. The shorter reaction time was beneficial for forming Ni₁₂P₅ NCs, and longer reaction time was beneficial for forming Ni₂P NCs. Furthermore, a possible growth mechanism of the as-synthesized nickel phosphide NCs was proposed. These synthetic techniques may be expanded to other metal phosphide materials.