Studies On The Preparation,Characterization And Properties Of Cu₂S Nano Materials

Because of the special optical and electrical properties of copper chalcogenides, there are plenty of reports about the efficient ways to prepare them,such as CuO,Cu₂O, which have been synthesized with multifarious morphologies like nanoparticles, nanorods,nanoplatelets,nanowires.However,there are a few investigations about the synthesis and property of Cu₂S.It is a p-type semiconductor,with a direct band gap of 1.2 eV.It can be used in solar cells,thin-film transistor for panel displays,electronic and optoelectronie chips,biosensors,etc.So,it is a potential semiconductor having many applications.In this paper,Cu₂S nanostructures were fabricated by a polyol process using Cu(CH₃COO)₂·H₂O and thioacelamide(TAA)as precursors and diethylene glycol as both solvent and reducing agent.The prepared nanostructures were characterized by X-ray diffraction(XRD)pattern,scanning electron microscopy(SEM),X-ray photoelectron spectra(XPS),transmission electron microscopy(TEM)and high resolution TEM (HRTEM).Additionally,UV-Vis diffusion reflection spectroscopy(UV-Vis)and fluorescence(PL)spectrometer were employed to record the optical properties of the nanostructures.Besides,the mechanisms of the crystallizationand photoluminescence were also discussed.Finally,the photocatalytic activity of Cu2S nanostructures was evaluated.The result shows that with the change of the reaction conditions,Cu₂S nanostructures with different morphology,such as vertically nanorod arrays,nanoflowers assembled by nanorod array,nanoparticles and nanowires,can be successfully prepared with control.The growth mechanism with the change of the conditions is proposed. Moreover,the prepared Cu2S nanostructures with different morphology have broad fluorescence emission in the range of 530-560 nm under the excitation wavelength of 250 nm.The peak location is also dependent on their nanostructures.The peculiar morphology of flower-like Cu2S possesses an excellent photocatalytic activity.The degradation efficiency of the dye Brillant Red under visible light can reach to 50.1%.Besides,Cu₂S-TiO₂,Cu₂S-CNTs and Cu₂S-CdS were fabricated by this way and all of them have different photocatalytic activity.The Cu2S-CdS degradation efficiency of the dye Brillant Red under visible light can reach to 68.0%.