Role of Alkylamines in Tuning the Morphology and Optical Properties of SnS(2) Nanoparticles Synthesized by via Facile Thermal Decomposition Approach

The present study reported the synthesis of SnS(2) nanoparticles by using a thermal decomposition approach using tin chloride and thioacetamide in diphenyl ether at 200 °C over 60 min. SnS(2) nanoparticles with novel morphologies were prepared by the use of different alkylamines (namely, octylamine (OCA), dodecylamine (DDA), and oleylamine (OLA)), and their role during the synthesis was explored in detail. The synthesized SnS(2) nanostructures were characterized using an array of analytical techniques. The XRD results confirmed the formation of hexagonal SnS(2), and the crystallite size varied from 6.1 nm to 19.0 nm and from 2.5 to 8.8 nm for (100) and (011) reflections, respectively. The functional group and thermal analysis confirmed the presence of organics on the surface of nanoparticles. The FE-SEM results revealed nanoparticles, nanoplates, and flakes assembled into flower-like morphologies when dodecylamine, octylamine, and oleylamine were used as capping agents, respectively. The analysis of optical properties showed the variation in the bandgap and the concentration of surface defects on the SnS(2) nanoparticles. The role of alkylamine as a capping agent was explored and discussed in detail in this paper and the mechanism for the evolution of different morphologies of SnS(2) nanoparticles was also proposed.