Preparation Of Copper Sulfide Micro/Nano Structured Materials With Different Morphologies And Its Photocatalytic Performance

In this paper, CuS micro/nanomaterials with different morphologies and sizes were successfully prepared by solvothermal, hydrothermal-microemulsion and hydrothermal method, and the photocatalytic properties of the product were also studied, respectively. The main content can be summarized as follows:Flower-like copper sulfide microsphere superstructures with diameters of 2.2~4.8μm comprising nanoflakes were successfully prepared via a solvothermal process, employing copper chloride and thiourea as starting materials, ethylene glycol as solvent. The as-obtained products were characterized by XRD, SEM, TEM, HRTEM and SAED techniques. The xenon lamp and high-pressure mercury lamp were used as light source to investigate the photocatalytic activity of CuS microspheres for the degradation of methylene blue. The results show that the CuS microspheres are hexagonal phase. It is also demonstrated that the morphologies of the products are greatly influenced by solvents, different sources of sulfur and copper salt, reaction temperature and reaction time. Photocatalytic tests reveal that the degradation rate of methylene blue is up to 98.7 % after illuminating for 30 min under 35 W Xenon Lamp, exhibiting higher photocatalytic activity in visible region. UV-Vis absorption and photoluminescence spectroscopy results show that the as-obtained CuS microspheres have strong absorption at the wavelengths of 269 nm and 494 nm, and its band gap is 2.0 eV. Photoluminescence spectrum has an emission band around 608 nm. In addition, the growth mechanism of the flower-shaped CuS crystals was also discussed.Hedgehog-shaped CuS hollow microspheres were successfully prepared via a hydrothermal microemulsion process, using CS2, ethylenediamine and CuCl2·2H2O as starting materials. The products were characterized by XRD,SEM,TEM and HRTEM means. The effects of different conditions such asω0, reactant concentration, reaction time and reaction temperature on the morphology and size of the products were studied. Photocatalytic performance of the CuS hollow microspheres was investigated by measuring the decomposition rate of methylene blue at room temperature. The results show that the prepared product is hexagnoal CuS hollow spheres, with a diameter of about 0.1~1.0μm. The crust of the microspheres are composed of many twisted nanoflakes, with edge length of 200~300 nm, thickness of about 10 nm. It is also demonstrated that the reaction temperature, reaction time, differentω0 value and reactant concentration have a great effect on the morphology and size of the final products. The photodegradation results indicate that the degradation rate of methylene blue reach 91.4 % after illuminating for 30 min under 35 W Xenon Lamp, exhibiting excellent visble-light photocatalytic activity. UV-Vis results indicate that product CuS has a strong adsorption at 443 nm and its band gap is around 1.8 eV. The fluorescence spectroscopy shows the emission spectral band at 365 nm and 486 nm, respectively. We have preliminarily studied the growth mechanism of hedgehog-shaped CuS hollow microspheres.Copper sulfide microspheres with diameters of 0.1~1.6μm were prepared by a facile hydrothermal process, using CuCl2·2H2O, CS2 and ethylenediamine as source materials. The samples were characterized by XRD, SEM, TEM, HRTEM and SAED techniques. Photocatalytic activity of CuS microspheres was investigated by decomposing of methyl orange solution at room temperature. The results show that the CuS microspheres are hexagonal phase. It is also demonstrated that the morphology of the products are greatly influenced by different sources of sulfur, reaction time and reaction temperature. UV-Vis results indicate that product CuS has a strong adsorption at 576 nm and its band gap is around 1.8 eV. The fluorescence spectroscopy shows the emission spectral band at 350 nm, 487 nm and 529 nm, respectively. Photocatalytic tests show that the degradation rate of methyl orange is up to 86.9 % after illuminating for 30 min under 35 W Xenon Lamp, exhibiting higher visble-light activity. In addition, the growth mechanism of the CuS microspheres was also proposed.