Formation of ZnIn2S4 nanosheets and tubular structures in organic media

Hot-injection method for synthesis of ZnIn2S4 (ZIS) in organic media was studied. Nanosized ZnIn2S4 is successfully synthesized in oleic acid/oleylamine mixture in different ratios, which are both: complexing and/or capping agents. Nanosheets/nanoscrolls of about 50 nm are obtained. The band gaps of synthesized nanostructures were calculated to be in the range from 2.6 to 3.0 eV, values which are increased compared to bulk value (2.3-2.5 eV). The increase of band gap can be assigned to nanodimensions of the particles. Potential of band edges is calculated using empirical equation and find to be in the range from -0.16 to -0.36 V for conduction band, and from 2.24 to 2.69 V for valence band. By using XRD and TEM techniques, crystal structure and morphology of obtained materials were investigated, and detailed formation and growth mechanism of nanosheets/nanoscroles is proposed accordingly. (C) 2016 Elsevier Ltd. All rights reserved.