Spectroscopy and Theoretical Modeling of Phonon Vibration Modes and Band Gap Energy of CuZnSn(S Se ) Bulk Crystals and Thin Films.

Semiconductor CuZnSn(S Se ) (CZTSSe) solid solution is considered as a perspective absorber material for solar cells. However, during its synthesis or deposition, any modification in the resulting optical properties is hardly predicted. In this study, experimental and theoretical analyses of CZTSSe bulk crystals and thin films are presented based on Raman scattering and absorption spectroscopies together with compositional and morphological characterizations.

Effect of non-stoichiometry of initial reagents on morphological and structural properties of perovskites CHNHPbI.

The properties of films of organic-inorganic perovskites CHNHPbICl depending on the ratio of starting reagents in solutions (PbI:{CHNHI + CHNHCl}) has been investigated. It was found that the formation of the perovskite structure with the ratio of the initial reagents PbI: CHNHI = 1:1 occurs at 70-80 °C, and with the increase of the temperature of thermal treatment to 120 °C, the thermal destruction of the perovskite begins. When the ratio of the starting reagents PbI: CHNHI = 1:2, the formation of the perovskite structure occurs through the intermediate compound (CHNH)PbI, and when the ratio is 1:3-(CHNH)PbI and (CHNH)PbI.