Yonghong Ni

A simple reduction-oxidation route to prepare Co3O4 nanocrystals

Abstract Cobalt oxide (Co3O4) nanoparticles have been successfully prepared via a simple reduction-oxidation route at room temperature and normal pressure, using cobalt chloride as the reactant and sodium acetate as the basic agent. Owing to employing a γ-irradiation technique, no extra reducing reagent was introduced into the system. The experiment contained two steps: first, cobalt (II) ions were reduced to cobalt atoms by γ-irradiation in nitrogen. Then, cobalt atoms were oxidized to cobalt oxide (Co3O4) in air. The TEM images showed that cobalt oxide powders consisted of crystallized spherical particles and amorphous wire-like particles.

Synthesis and characterization of polyacrylonitrile–silver nanocomposites by γ-irradiation

The nanocomposites of stable nanosilver particles embedded in polyacrylonitrile matrix were synthesized by γ-irradiation, in which the monomer acrylonitrile was polymerized and the silver ions were reduced simultaneously by γ-irradiation to form composites in situ. The strong interactions between silver ions with –CN groups of polyacrylonitrile are found, which were confirmed by X-ray powder diffraction, IR spectrum and absorption spectra.

γ-Irradiation preparation of CdS nano-particles and their formation mechanism in non-water system

Abstract Cadmium sulfide nano-particles with mean size of 2.3xa0nm have been successfully prepared by irradiating an ethanol solution of cadmium chloride and carbon disulfide with 60Co γ-ray. The product is characterized by X-ray powder diffraction, transmission electron microscopy and X-ray photo-electron spectrum, respectively. The influence of the irradiation dose on the size of cadmium sulfide nano-particles is investigated by UV–VIS absorption spectrum. A possible mechanism for the formation of cadmium sulfide nano-particles in ethanol system is proposed according to the result of experiments.

A novel route to prepare cadmium sulfide nano-rods

Cadmium sulfide nano-rods were successfully prepared by γ-irradiation at room temperature and ambient pressure using urea as the template. XRD pattern showed that the phase of the product was hexagonal. The morphology and the size of cadmium sulfide particles were viewed by TEM. Its formation process was described and some influencing factors were investigated.

In situ single-step synthesis of gold/polyacrylamide nanocomposites in an ethanol system

Abstract Au/polyacrylamide (Au/PAM) nanocomposites were successfully prepared in situ by γ (gamma)-irradiation in an ethanol system. The products were characterized by some means including X-ray powder diffraction (XRD), transmission electron microscopy (TEM), IR and UV–VIS spectra. Based on two-aspects, ethanol was used as the solvent. Firstly, it is a very good solvent like water. A lot of inorganic salts and organic monomers can dissolve in it. Secondly, ethanol is also a polar substance. Thus, solventional electron can be easily produced in it during γ-irradiation, which is an important media in the system and plays a crucial role in the synthesis of composites.

Synthesis and characterization of spherical MS (M=Cd, Zn) nanocrystalline in a quaternary W/O microemulsion by γ-ray irradiation

Abstract Spherical semiconductor metal sulfide (metal includes Cadmium and Zinc) nanocrystalline is successfully synthesized in a quaternary W/O microemulsion by γ-ray irradiation at room temperature under ambient pressure. XRD, TEM, XPS, UV–Vis and PL spectra are used to characterize the obtained product. A possible reaction process is discussed at the end of this paper.

Synthesis and characterization of α-FeO(OH) nano-rods in situ via a solution-oxidation

Abstract α-FeO(OH) nano-rods were synthesized in situ by a simple solution-oxidation reaction at room temperature. The product is characterized by XRD, TEM, XPS and IR, respectively. It was found that the product could be obtained directly in solution when sodium acetate instead of sodium hydroxide was used as the basic agent. The influence on the size and morphology of the product was also studied.