Preparation of monoclinic Cu2SnS3 single crystal by chemical vapor transport with iodine

Abstract Single crystals of monoclinic Cu 2 SnS 3 (CTS) were prepared by chemical vapor transport using iodine as a transport agent. A range of iodine concentrations from 1.5 to 3.0 mg/cm 3 was employed to determine its effect on crystal growth. The crystals were quenched after vapor transport to prevent the growth of additional, secondary CTS phases. A stoichiometrically balanced CTS product (with a composition ratio of Cu:Sn:S=2.05:1.01:2.94) was achieved using an iodine concentration of 2.0 mg/cm 3 . The results of Raman scattering and X-ray diffraction analyses showed that the samples were CTS crystals with a monoclinic structure. The sample was confirmed to be a single crystal by selected-area electron diffraction patterns, which showed a regular array of spots consistent with monoclinic CTS.