Preparation And Characterization Of Ni₂P/Ni₁₂P₅ Micro/Nano Material

Due to their novel structures and superior properties, nickel phosphides have been considered as obbligato materials in many reactions. The synthesis of nickel phosphide with novel morphology and excellent performance has been being a research focus for researchers. At the same time, the control of uniform size and morphology is an awkward problem for nickel phosphide research. Herein, Ni2 P and Ni12P5 microcrystals were successfully fabricated via hydro-/solvothermal route. Based on a series of dependent experiments, the optimum reaction conditions and the formation mechanism of as-prepared samples were discussed. Furthermore, the performance of as-prepared products was tested and the theoretical reason was analyzed. Our work is summarized as follows:(1) 3D flower-like microstructural nickel phosphide(Ni12P5) was successfully synthesized by a facile solvothermal route. XRD and FE-SEM images demonstrated the as-prepared Ni12P5 microstructure had a tetragonal phase and were composed of a large quantity of flower-like structure. Based on a series of the time-dependent experiments, the formation mechanism of flower-like Ni12P5 microstructures were discussed. It was found that the as-prepared flower-like microstructures are assembled by many spherical particles. In addition, the results exhibited the as-prepared flower-like Ni12P5 microstructures possess excellent photocatalytic activity and could photocatalytically degrade some typical organic dyes under the irradiation of UV light.(2) Uniform single-crystal Ni2 P hollow spheres with an average diameter of 200 nm were successfully synthesized via a solvothermal route at 180℃ for 16 h in presence of mixed surfactant of sodium dodecyl benzene sulfonate/cetyltrimethyl ammonium bromide(SDBS/CTAB). The phase composition, morphologies and adsorption activities of the samples were confirmed by XRD, FE-SEM, TEM, SEAD, and HRTEM. The results exhibited the as-prepared hollow spheres would be obtained only using the mixtures of CTAB and SDBS with a mass ratio of 7:3 rather than single CTAB or pure SDBS. Furthermore, it turned out that the single-crystal Ni2 P hollow spheres could exhibit excellent adsorption activity for Mountain green organic dyes.(3) In this paper, Ni2 P solid spheres and Ni12P5 yolk-shell microspheres have been fabricated successfully via two different hydrothermal systems, using sodium dodecyl benzene sulfonate/sodium dodecyl sulphate(SDBS/SDS) and sodium dodecyl benzene aasulfonate/cetyltrimethyl ammonium bromide(SDBS/CTAB) as stabilized system, respectively. The yolk-shell Ni12P5 spheres exhibit the size of around 900 nm, which make up mainly the shells with a thickness of 110 nm and the cores with a diameter of 350 nm on average. As the heating time increases from 0 to 36 h, Ni12P5 structures transform from yolk–shell microspheres to a hollow spheres. Based on a series of surfactant-dependent and time-dependent experiments, the optimum proportion of mixed surfactant and the formation mechanism of Ni12P5 yolk–shell microstructures were discussed. Importantly, the as-prepared Ni2 P and Ni12P5 possess excellent photocatalytic activity for Congo red(CR) and Safranine T dyes.