Solvent-controlled syntheses of Ni12P5 and Ni2P nanocrystals and photocatalytic property comparison

Nickel phosphide nanocrystals with various phases have been successfully synthesized via a simple solvothermal route at 180 °C for 16 h, employing nickel chloride and white phosphorus (WP) as starting reactants in the presence of sodium dodecylbenzene sulfonate (SDBS). X-ray powder diffraction (XRD) research showed that the pure Ni12P5 phase with a high yield could be obtained in an ethanol solution, and the pure Ni2P form was prepared in a mixed system with the volume ratio of water/ethanol of 10:10. Namely, the presence of water molecules induced the phase conversion of nickel phosphides. Furthermore, in order to investigate the correlation between properties and phases, as a case, the photocatalytic degradation abilities of two nickel phosphide phases for organic dyes were compared.

► Ni12P5 and Ni2P have been selectively prepared via a facile solvothermal route in the presence of SDBS.
► Nickel chloride and white phosphorus were selected as the starting reactants.
► The water/ethanol volume ratio played a crucial role in the phase control of nickel phosphide.
► Ni2P possesses a stronger capacity for the degradation of Safranin T than Ni12P5.