Controlled Synthesis Of Metal Sulfides With Complex Nanostructures

Metal sulfides nanomaterials are a group of important semicunductors with a wide range of application. This paper uses mild and simple hydrothermal method to synthesis some important metal sulfides nanomaterials. It is aimed at controlling the product, morphology, the size and doing some research for the optical properties of them. Furthermore, many modern techniques including X-ray powder diffraction (XRD), Energy dispersive X-ray spectroscopy (EDX), Field emission scanning electron microscope (FE-SEM), high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy (Raman), UV absorption spectra (UV-vis), Photoluminescence spectra (PL), etc., were used to characterize the structure, phase, composition, morphology, size and the optical properties of as-synthesized products. The main elements have been completed are summarized as follows:1. Using F-containing coordination compounds as precursors, three-dimensional (3D) CuS hierarchical microspheres (the diameter of microspheres were1-3μm, nanosheets thickness were about20nm) were synthesized by a novel precipitate-converting-hydrothermal-synthesis reaction at120℃for6h without any surfactant or template. The obtained products were characterized by XRD, EDX, FTIR, Raman, FE-SEM and HRTEM to investigate the reaction time, concentration, tempereture, etc how to affect the structure, phase, composition, morphology, size of the products. Besides, the optical properties and thermal stability of the as-synthesized CuS3D microspheres were also studied.2. Using oxalate as precursors, hollow structure sulfides (CuS, ZnS and PbS) were synthesized by precipitate-converting hydrothermal and solvothermal synthesis:(a) hollow sphere-like morphologies of copper sulfide nanostructures (the diameter of hollow spheres were1-2μm, nanosheets thickness were about50nm) were synthesized from the reaction of Cu(NO3)2·3H2O, H2C2O4and Na2S·9H2O at120℃for6h via a hydrothermal method. It was discussed that the solvent concentration, tempereture, and the reaction time have great influence on the morphology and size of the resulting CuS products. Besides, the optical properties of the as-synthesized CuS hollow spheres were also studied.(b) hollow sphere-like morphologies of zinc sulfide nanostructures (the diameter of hollow spheres were2μm, the diameter of polyhedrons were about50nm) were synthesized from the reaction of Zn(NO3)2·3H2O, Na2C2O4and Na2S·9H2O at180℃for12h via a solvothermal method. The controlled preparation of ZnS nanocrystals with different phases and morphologies could be achieved only by changing the ratio of ethanol to water. The optical properties of the obtained ZnS nanocrystals with different phases were investigated.(c) hollow tube-like morphologies of lead sulfide nanostructures (the diameter of hollow tubes were1-2μm, the diameter of nanoparcles were about80nm) were synthesized from the reaction of Pb(NO3)2, Na2C2O4and Na2S·9H2O at180℃for12h via a hydrothermal method. The structure, composition, morphology, size of the obtained products were characterized by XRD, EDX, Raman, FE-SEM and HRTEM. The possbile formation mechanism of hollow structures was also proposed.3. Using sulphate and carbonate as precursors, cage-like and rod-like PbS were synthesized by precipitate-converting hydrothermal-synthesis:(a) hollow cage-like morphologies of lead sulfide structures (the diameter of hollow cages were2μm, the diameter of cubes were about200nm) were synthesized from the reaction of Pb(NO3)2, Na2SO4and Na2S·9H2O at180℃for12h via a hydrothermal method. The possbile formation mechanism of hollow cage-like structures was also proposed.(b) rod-like morphologies of lead sulfide structures (the length of rods were1-3μm, the diameter of nanoparcles were about60nm) were synthesized from the reaction of Pb(NO3)2, Na2CO3and Na2S·9H2O at180℃for12h via a hydrothermal method. The structure, composition, morphology, size of the obtained products were characterized by XRD, EDX, Raman, FE-SEM and HRTEM.