Investigation of single phase $Cu_{2}ZnSn_{x}Sb_{1−x}S_{4}$ compounds processed by mechanochemical synthesis

Physical review materials 2(7), 075404 (2018). doi:10.1103/PhysRevMaterials.2.075404
The copper zinc tin sulfide (CZTS) compound is a promising candidate as an alternative absorber materialfor thin-film solar cells. In this study, we investigate the direct formation of Cu1.92ZnSnx (Sb1−x )S4 compounds[CZT(A)S], with x = 1, 0.85, 0.70, and 0.50, via a mechanochemical synthesis (MCS) approach, starting frompowders of the corresponding metals, zinc sulfide, and sulfur. The thermal stability of theCZT(A)S compoundswasevaluated in detail by in situ synchrotron high-energy x-ray diffraction measurements up to 700 °C. The CZT(A)Scompounds prepared viaMCS revealed a sphalerite-type crystal structure with strong structural stability over thestudied temperature range. The contribution of the MCS to the formation of such a structure at room temperatureis analyzed in detail. Additionally, this study provides insights into the MCS of CZTS-based compounds: thepossibility of a large-scale substitution of Sn by Sb and the production of single phase CZT(A)S with a Cu-poor/Zn-poor composition. A slight increase in the band gap from 1.45 to 1.49–1.51 eV was observed with theincorporation of Sb, indicating that these novel compounds can be further explored for thin-film solar cells.
Published by APS, College Park, MD