A photochemical method for controlling the size of CdS nanoparticles

2019-09-24 23:05:35

illumination size nanoparticles CdS capping

责任者: Marandi, M.;Taghavinia, N.;Iraji Zad, A.;Mahdavi, S.M. 单位: Physics Department, Sharif University of Technology, Tehran 14588, Iran 来源出处: Nanotechnology,2005,16(2):334-338 摘要: The optical and electrical properties of semiconductor nanoparticles are strongly dependent on their size. A flexible control of the size of the nanoparticles is of interest for tuning their properties for different applications. Here we use a coupled method to control the size of CdS nanoparticles. The method involves the photochemical growth of CdS nanoparticles together with the use of a capping agent as an inhibiting factor. CdS nanoparticles were formed through a photoinduced reaction of CdSO4 and Na2S2O3 in an aqueous solution. Mercaptoethanol (C2H6OS) was used as the capping agent, and we investigated the effect of illumination time, illumination intensity and the concentration of capping agent on the nanoparticle size. Transmission electron microscopy (TEM) shows crystalline nanoparticles with relatively low dispersion. Optical absorption spectroscopy was mainly used to measure the band gap and size of the nanoparticles. Increasing the illumination time or illumination intensity increases the nanoparticle size, while higher capping agent concentration leads to smaller nanoparticle size. A band gap range of 2.75-3.4 eV was possible with our experimental conditions, corresponding to a 3.2-6.0 nm size range. 关键词: Nanostructured materials;Cadmium sulfide;Photochemical reactions;Semiconductor materials;Crystalline materials;Surface active agents;Energy gap;Light absorption;Diffusion;Optoelectronic devices;Synthesis (chemical);Transmission electron microscopy;CdS nanoparticles;Semiconductor nanoparticles;Photochemical growth;Capping agents