Characterization of Crystalline Cu_2SnS_3 Synthesized via Low Temperature Solvothermal Method

摘要

Cu_2SnS_3 flower-like nanoparticles consisted of nano-flakes were successfully produced using solvothermal technique at 120°C for 12 h. The precursors used in this process were CuCl_2.2H_2O, SnCl_2.2H_2O, and thiourea with dimethyl sulfoxide (DMSO) as a solvent. The results showed that the as-obtained product was triclinic Cu_2SnS_3 with secondary phases CuS and SnS, and after annealing process, a pure triclinic was obtained. The crystal structure of the obtained samples was investigated by X-ray diffraction which assured the obtained data and the average crystallite size of as-prepared and annealed CTS was found to be 18.42 and 31.6 nm, respectively. Scanning electron microscopy (SEM) showed that the surface morphology has the shape of flower like consisted of nano flakes. The transmission electron microscope (TEM) displayed the formation of sheets. The band gap was measured using UV-Vis absorption spectroscopy and found that the as-prepared sample has 1.97 eV band gap, which obtained for various phases CuS and SnS. However, this band was changed to 1.26 eV upon the heat treatment at 500°C for 10 minutes. This value of E_g is comparable with the value reported by other literatures.