Study On The Growth Mechanism Of Nano Zinc Sulfide Based On Small Angle X-ray Scattering

Small angle X-ray scattering(SAXS)has been developed as a technique and means to study the submicron structure and morphological characteristics.It is widely used in the fields of polymers,biomacromolecules,condensed matter physics and materials science.The small angle X-ray scattering can capture the electron density inhomogeneities within the nano-scale(1-100)and reflect the structure information in the two-dimensional scattering pattern.Therefore,the structure information can be obtained by solving SAXS spectra.Zinc sulfide(ZnS),as a typical Ⅱ-Ⅵ wide band gap semiconductor material,is one of the best substrates for electroluminescence.It has been widely used in the fields of photoelectric conversion,nonlinear optics and flat panel display.The growth of ZnS nanoparticles and the growth rate of ZnS nanoparticles are the important factors influencing the industrial controllable mass production of ZnS.Therefore,it is very important to study the growth mode of ZnS nanoparticles.SAXS can track the particle size of ZnS nanoparticles with time evolution relationship,therefore it has been recognized as an effective means to characterize the structure of nano-materials information.This paper describes the fundamental theories,experimental methodologies,and application of synchrotron radiation and small-angle X-ray scattering(SAXS),in an effort to study the growth process of ZnS nanoparticles in solution.The process of particle shape,size and distribution is analyzed and we finally obtain its growth mode.Main works include:1.A sample tank for the growth of ZnS nanoparticles was designed by combining the characteristics of small-angle X-ray scattering technique and the parameters of the small-angle station of Beijing Synchrotron Radiation Facility 1W2A.2.The tangent-by-tangent method is applied to SAXS data processing.This method is a practical application of Guinier’s law.Therefore,for any shape of nanoparticle system,the distribution function of the radius of gyration can be obtained by step-by-step tangent method.3.The size of the ZnS nanoparticles with the concentration of the reactants and the time of the reaction were studied by using SAXS technique.The size of ZnS nanoparticles at different reactant concentrations can be obtained by the combination of UV-vis,DLS and TEM,and then the time course of ZnS nanoparticles can be obtained.For growth mechanism of ZnS nanoparticle in ethanol is dominated by Ostwald-ripening mechanism and accompanied by oriented attachment.