Facile synthesis, spectral properties and formation mechanism of sulfur nanorods in PEG-200

The synthesis of nano-sulfur sol by dissolving sublimed sulfur in a green solvent-PEG-200 was studied. Homogeneous rod-like structure of sulfur with a typical diameter of about 80 nm and an average aspect ratio of 6–8 was obtained. The structure, morphology, size, and stability of the products were investigated by transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and dynamic light scattering (DLS) measurements. The spectral properties of the products were investigated by ultraviolet-visible (UV–vis) absorption and resonance Rayleigh scattering spectroscopy (RRS). The results showed that the spherical sulfur nanoparticles could self-assemble into nanorods in PEG-200. During the self-assembling process, the absorption band showed a red shift and the RRS intensity enhanced continuously. There was physical cross-linking between PEG and sulfur nanoparticles. PEG-200 induced the oriented attachment of sulfur nanoparticles by the terminal hydroxyl groups. This research provides a greener and more environment-friendly synthetic method for the production of sulfur nanorods.