Preparation And Photoluminescence Study Of CdS/PAN Composite Nanofibers

Nano-scaled semiconducting materials have attracted considerable attentions due to their unique electrical and optical properties as well as their chemical and physical properties. Among theâ…¡-â…¥semiconductors, cadmium sulfide (CdS) has a direct band gap of 2.4 eV. When the particle size becomes comparable to the Bohr diameter, the quantum efficiency increases. Materials with different optical properties can be prepared via controlling the CdS particle size and size distribution, and were widely applicated in optoelectronic devices.In this paper, we designed a combination of solvothermal treatment and electrospinning methods for the preparation of semiconductor functional material with a combination of nanofiber materials, using electrospinning firstly polyacrylonitrile and cadmium nitrate into a precursor one-dimensional fiber, after hydro-and solvothermal treatment, under the premise of not undermining the structure of fibers, let the cadmium nitrate embedded in fibers under the conditions of heat of the treatment and the slowly release and reacted with sulfide ions in the solution to produce CdS/PAN composite nanofibers, a new type of nano-materials. The influences of synthetic conditions on the growth of CdS nanostructures were studied in details. And we compared the two samples synthesized in hydrothermal and solvothermal treatment.Scanning electron microscopy(SEM), X-ray diffraction(XRD), Fourier transform infrared (FT-IR), and Photoluminescence(PL)spectra were employed to examine the structures, morphologies , micro-structure ,optical properties of the products. The main results of the dissertation are summarized as follows: the changes of concentration , time and temperature have no influences on the morphologies but the size and the density distribution; the composite fibers have luminous property because of the surface defection; the CdS particles combined with PAN via physical acting force not chemical acting force; the CdS particles synthesized in distilled water wrer with larger size, low density, and stronger surface defection compared with the particles synthesized in solvothermal treatment.Ultrathin fibers which control the 1-D nanostructure of the composite were fabricated by electrospinning, combinated with hydro- and solvothermal , research different experiment routes and the reaction conditions, by which kinds of semiconductor functional materials with One-dimensional nanostructures were synthesized, and developed a simple and effective way to the preparation of one dimensional structure, and the new method of establishing the foundation.