Synthesis and structural characterization of Ag2ZnSnS4 crystals

In today’s battle for the environment, renewable energy sources, including solar energy, plays a significant role. Therefore, it is necessary to develop new materials for solar cells. Ag2ZnSnS4 (AZTS) is a material that makes it possible to increase the efficiency of photovoltaic modules, compared to cells based on Cu2ZnSnS4. AZTS was obtained by several methods, but in these research it was synthesized by Chemical Vapor Transport method (CVT), using zinc chloride as transporting agent, for the first time. X-ray powder diffraction was used in the structural tests, which showed that through the CVT method it is possible to obtain a pure Ag2ZnSnS4 phase with a stannite crystal structure. Raman measurements were conducted to determine the crystal quality of samples and to check their phase homogeneity. Raman spectra were calculated from DFT analysis applying the LDA and GGA approximations. The measured Raman peaks were assigned to calculated ones for AZTS structure.