Monodispersed Ni nanoparticles were successfully prepared by chemical reduction with hydrazine hydrate in ethylene glycol. The effect of the amount of polyvinylpyrrolidone （PVP-K30） on the preparation of Ni nanopart...Monodispersed Ni nanoparticles were successfully prepared by chemical reduction with hydrazine hydrate in ethylene glycol. The effect of the amount of polyvinylpyrrolidone （PVP-K30） on the preparation of Ni nanoparticles was investigated. X-ray diffraction （XRD）, transmission electron microscopy （TEM）, and high resolution transmission electron microscopy （HRTEM） were employed to characterize the nickel powders. The average nickel particle size can be controlled from 103 nm to 46 ran with increasing the mass ratio of PVP to NiCl2·6H2O. The particles are spherical in shape and are not agglomerated. A possible extensive mechanism of nickel nanoparticle formation has been suggested.展开更多
Semiconductor CdS nanoparticles were synthesized by the sonochemical reduction of a mixed aqueous solution of CdCl2, Na2S2O3 and (CH3)CHOH in Ar atmosphere at room temperature. The results of a detailed investigation ...Semiconductor CdS nanoparticles were synthesized by the sonochemical reduction of a mixed aqueous solution of CdCl2, Na2S2O3 and (CH3)CHOH in Ar atmosphere at room temperature. The results of a detailed investigation with X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectrum and optical absorption spec-troscopy are reported. A clearly red shift of the absorption edge and a broad absorption band related to the surface states of nanoparticles have been observed in the optical absorption spectra with the increasing of CdS particle size. The mechanisms of the CdS nanoparticle formation and size growth during sonochemical irradiation were discussed. This convenient method is found to be an efficient way to produce other chalcogenides as well.展开更多
文摘Monodispersed Ni nanoparticles were successfully prepared by chemical reduction with hydrazine hydrate in ethylene glycol. The effect of the amount of polyvinylpyrrolidone （PVP-K30） on the preparation of Ni nanoparticles was investigated. X-ray diffraction （XRD）, transmission electron microscopy （TEM）, and high resolution transmission electron microscopy （HRTEM） were employed to characterize the nickel powders. The average nickel particle size can be controlled from 103 nm to 46 ran with increasing the mass ratio of PVP to NiCl2·6H2O. The particles are spherical in shape and are not agglomerated. A possible extensive mechanism of nickel nanoparticle formation has been suggested.
基金This work was supported by the National Key Basic Research Project(G1999064501)the Natural Science Foundation of Anhui Province(No.01044903).
文摘Semiconductor CdS nanoparticles were synthesized by the sonochemical reduction of a mixed aqueous solution of CdCl2, Na2S2O3 and (CH3)CHOH in Ar atmosphere at room temperature. The results of a detailed investigation with X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectrum and optical absorption spec-troscopy are reported. A clearly red shift of the absorption edge and a broad absorption band related to the surface states of nanoparticles have been observed in the optical absorption spectra with the increasing of CdS particle size. The mechanisms of the CdS nanoparticle formation and size growth during sonochemical irradiation were discussed. This convenient method is found to be an efficient way to produce other chalcogenides as well.
