Great influence of a small amount of capping agents on the morphology of SnS particles using xanthate as precursor

Abstract

Several hierarchical tin sulfide (SnS) architectures have been prepared based on the reaction of tin dichloride (SnCl 2·2H 2O) with potassium O-ethyldithiocarbonate (ethylxanthate, C 2H 5OCS 2K) via a solvothermal route in N, N-dimethylformamide (DMF) solution at 180 °C for 24 h. By varying experimental parameters such as reaction temperature, reaction time and the ratios of reactants, various morphologies of three-dimensional (3D) superstructures assembled by SnS nanosheets, nanoribbons and nanorods were obtained. The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). For a typical molar ratio of C 2H 5OCS 2K/SnCl 2 = 2, the addition of a slight excess of C 2H 5OCS 2K (molar ratio of C 2H 5OCS 2K/SnCl 2 = 2.4) resulted in one-dimensional growth of lamellar SnS particles and their assembly into flowerlike superstructures. Similarly, for the molar ratio of C 2H 5OCS 2K/SnCl 2 = 2, if a small amount of capping agent (1 mL potassium oleate in 40 mL DMF solution) was employed, SnS microspheres aggregated by nanorods were formed. Possible mechanisms for the formation of 3D SnS microstructures were proposed. Optical properties of the products were also studied.