Preparation Of Cds Nanoparticles And Their Photoelectric Catalytic Properties

As one of semiconductor materials CdS is of great for the solar cell and other opoelectronic products. For the bulk CdS the band gap is 2.45 eV at room temperature. With the development of nanotechnology CdS nanoparticles have drawn much attention recently due to enhanced semiconducting properties. A variety of synthetic methods have been developed for CdS nanoparticles, and the diameter, uniformity, purity, and other properties of particles are different depending on the preparing conditions and methods.This dissertation studied on the preparation of nano-sized CdS and its photocatalytic and bioelectrocatalytic properties. A novel anti-phase micelle method for the preparation of CdS nanoparticles has been developed using ultrasound oscilator. The CdS nanoparticles were analyzed by FT-IR, XRD, DTG-DTA, TEM, UV-vis and fluorescence spectroscopy. The results indicated that the surfaces of the CdS nanoparticles were modified with CTAB. The mean particle size was about 5nm. Its structure wasβ-CdS. UV-vis spectrum of CdS nanoparticles showed that there is a blue-shift in the absorption band.We have studied the photocatalytic degradation of organic dye, the results indicated that CdS nanoparticle has very good photocatalytic activities. The photocatalytic degradation of methyl orange in the aqueous solution was investigated using the sun light as the photosource and CdS as the catalyst prepared with the anti-phase micelle method. The effects of the amount of the catalyst, the initial pH of solution and the initial concentration of methyl orange were discussed. The results demonstrated that CdS nanoparticles prepared with the anti-phase micelle method could degrade the methyl orange using the solar energy. When the initial concentration of methyl orange was 20 mg/L, initial pH of solution was 7.1 and the amount of the catalyst was 0.125g/L, the decolorization ratio was higher than 90% after 8 min irradiation.CdS nanoparticles cast on the glassy carbon (GC) electrode was used to immobilize redox protein. The CdS nanoparticles could provide a favorable microenvironment for direct electron transfer of the immobilized proteins. In addition, the immobilized redox protein showed stable bioelectrocatalytic activity for the reduction of H₂O₂.