Polymer/copper indium sulfide (CIS) nanocomposite solar cells are prepared via a capper free in situ preparation route using copper and indium xanthates as precursors, which decompose and form CIS nanoparticles in the polymer matrix during a mild thermal treatment. The solar cells generate current in a wide range of the solar spectrum and exhibit efficiencies up to 2.8%.
The formation of copper indium disulfide nanoparticles via the oleylamine route using copper iodide, indium chloride, and elemental sulfur has been investigated by applying conventional thermal heating as well as microwave irradiation. Oleylamine thereby acts as a capping ligand as well as a solvent. In an initial set of experiments, the onset of the reaction was determined to be around 115 °C by an in situ X-ray study using Synchrotron radiation. Using comparatively low synthesis temperatures of 120 °C, it is already possible to obtain nanoparticles of 2-4 nm with both heating methods but with irregular shape and size distribution. By applying higher temperatures of 220 °C, more crystalline and larger nanoparticles were obtained with slight differences in crystallite size and size distribution depending on the synthesis route. The size of the nanoparticles is in the range of 3-10 nm depending on the heating time. Using microwave irradiation, it is possible to obtain nanoparticles in only 90 s of total synthesis time. Control experiments to probe a nonthermal microwave effect were carried out ensuring an identical experimental setup, including the heating profile, the stirring rate, and the volume and concentration of the solutions. These experiments clearly demonstrate that for the preparation of CuInS(2) nanoparticles described herein no differences between conventional and microwave heating could be observed when performed at the same temperature. The nanoparticles obtained by microwave and thermal methods have the same crystal phase, primary crystallite size, shape, and size distribution. In addition, they show no significant differences concerning their optical properties.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.