Synthesis of Flower Shaped CuInS2Microparticles by One-Pot Polyol Method

Among the candidate semiconductors in photovoltaic applications، CuInS2 (CIS) is under intense investigation due to its direct band gap (1. 5eV)، high absorption coefficient and good stability. One of the limiting parameters in the mass production of these solar cells is that Indium is a rare metal which has to be substituted with other metallic elements. On the other hand، the maximum photovoltaic conversion efficiency is attained on devices with the absorber bandgap energy of approximately 1-1. 3 eV. So in this study، CIS synthesis and substitution of trace element of indium with abundant element of Iron were investigated. The solid solution compounds of CuIn1-xFexS2 were synthesised using one pot Polyol route. The synthesized powders were characterized using X-ray diffraction (XRD)، Scanning electron microscopy (SEM) and Scanning tunneling Spectroscopy (STS) techniques. As the amount of Iron increases up to x=0. 15، the crystallinity of particles is inhanced and their unit cell dimensions are reduced. Further increasing of iron content results in the formation of FeS and FeS2 as impurity phases were observed with further increasing the iron content، while the crystalinity is reduced. The density of states investigation confirmed that increasing the amount of Iron resulted in enhancing the density of carriers، p-type conductivity and formation of the intermediate band in the forbidden band of host material