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A novel sonication method has been successfully developed for the preparation of anthracene nanoparticles. The as-prepared nanoparticles are characterized using transmission electron microscopy, ultraviolet-visible absorption spectroscopy, fluorescence excitation and emission spectroscopy. Nanoparticles prepared with sonication are smaller and better dispersed than with magnetic stirring. Surfactants cetyltrimethylammonium bromide, bis(2-ethylhexyl)sodium sulfosuccinate, sodium dodecyl sulfonate and polyvinylpyrrolidone are used to control the size and morphology. Excimer band is found at 445 and 472 nm and possible mechanism is discussed.

The synthesis and characterization of a highly ordered macroporous CdS with regular arrays of spherical pores comparable to optical wavelengths are discussed. The sample has been successfully fabricated using colloidal crystal of poly (styrene-acrylic) (PSA) spheres as templates. The pore size is tunable in the range of 100–400 nm based on the size of PSA spheres. Transmission electron microscope (TEM) and scanning electron microscope (SEM) show that the exactly three-dimensional structure of the template has been imprinted in the final materials. XRD pattern indicates that the walls of the macroporous material are composed of 4 nm CdS nanoparticles making the absorption spectrum shift blue. The sample was also characterized by Raman spectroscopy and photo luminescent spectra (PL).

Star-shaped CdS patterns, which were composed of rod-like nanoparticles with diameters of 4–7 nm and lengths ranging from 150 to 200 nm, were successfully prepared by a convenient microemulsion technique at room temperature. It was found that the hydrophobic carbon chain of surfactant played an important role in controlling the morphology of the product. The present convenient microemulsion method is relatively mild and low toxic. It may provide a new route to the production of other metal sulfide patterns at room temperature.

CdS nanocrystals with various morphologies have been successfully fabricated in the C2H5OH and H2O solvents using sodium dodecyl sulfate (SDS) as capping material. CdS nanocrystals were formed via precipitation of Cd2+ ions with homogeneously released S2− ions from the decomposition of thioacetamide (TAA, CH3CSNH2) under the mild ultraviolet irradiation at room temperature. It was found that the capping material SDS in the solvents with different volume proportions of C2H5OH and H2O has much influence on the morphology of CdS nanocrystals. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) were employed to characterize the products. This study may provide a conveniently method to control shape other metal sulfide semiconductor nanocrystals.