| Owing to their suitable band gaps, high absorption coefficients and large atomic number, Cd-basedⅡ-Ⅵcompounds such as CdTe, CdS and CdZnTe are the most promising materials for solar cells and radiation detectors. In this thesis, first, we reviewed the applications of Cd-basedⅡ-Ⅵcompounds as solar cells,γ– and X– detectors, then took a further work in the preparation technique for CdTe polycrystalline films, at last introduced the principle of Rietveld method and made a preliminary application in the samples synthesized by hydrothermal method.Four aspects of our work are given in the body of this thesis: (1) we designed a system based the vacuum evaporation instrument to realize the closed-space sublimation technique and preliminarily studied the deposition temperature of this system; (2) texture-tuned growth CdTe thin films were grown on indium tin oxide (ITO) glass substrates by closed-space sublimation (CSS) method using the system we designed, and the optical absorption characteristics of the films were investigated; (3) nanostructure growth CdTe thin films were prepared by CSS using the system we designed, and the growth process was deduced according to the XRD, SEM analysis; (4) reviewed the history of Rietveld method and introduced the principle of Rietveld structure refinement, then refined the crystal structure of NiS2, FeS2 synthesized by hydrothermal method using Rietveld method.Some main conclusions obtained through the above work are as follows: (1) in the system we designed the increasing rate of temperature of Ni slice and substrate depends on the different current changing conditions, besides, the shape of Ni slice influences directly on the minus temperature between the source and the substrate; (2) the textures of the films prepared by CSS using the system we designed depend on the heating current increasing rate which does not greatly affect the CdTe band gaps; (3) nanostructure growth CdTe thin films which have various morphologies can be grown by CSS which is low cost and high production; (4) according to the results of Rietveld refinement, we find the unit cell parameters of NiS2 and the impurity phase Ni3S4 have reversed changing tendency; according to the quantitive phase analysis, the proper reaction temperature of synthesizing FeS2 by hydrothermal method is 180℃, because at this reaction temperature the content of the impurity phase of marcasite is the lowest. |
