The influence of reaction temperatures and volume of oleic acid to synthesis SnS nanocrystals by using thermal decomposition method

We report synthesis of SnS nanocrystals and their size variation with the reaction temperature, and volume of the oleic acid (OA) solvent. These nanocrystals were synthesized by using a tin precursor, Sn(OA)_x prepared by tin oxide (SnO) with different moles of oleic acid and a mixture of sulfur and oleylamine (OLA) was injected into the solution at different temperatures under argon atmosphere by using thermal decomposition method. The SnS nanocrystals show orthorhombic crystal structure, and the average particle size is increased from 20 nm to 50 nm and finally 200 nm with an increase in temperature from 150 C to 180 C and to 210 C. Careful observations indicate a gradual change in the shape of these nanocrystals from spherical to sheet like structure with the increase of the volume of oleic acid (2-5 mmol). The tin sulfide (SnS) films were grown by spin-coating method and subsequently the film was applied as an absorber for solar cells. The as-prepared SnS samples and films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to investigate the structure, phase composition, surface morphology and microstructure. The optical properties of SnS films were studied by using UV-visible spectroscopy.