Pure single-crystalline bismuth (III) sulfide (Bi2S3) nanowires with lengths of the long and short axes being 1.58–1.75 μm and 40 nm were prepared by a simple surfactant-assisted reflux method in the presence of thioacetamide, which served as both the sulfur source and a “soft template” in the formation of bismuth sulfide nanostructures. The effects of different surfactant, surfactant molecular weight, solvent medium, and sulfur source on the morphology, structure, and phase composition of the as-prepared Bi2S3 products were discussed. The formation of long Bi2S3 nanowires was probably via the mechanism of pyrolysis of bismuth (III) sulfide complexes dimer and continuous growth of crystalline nuclei along rod-shaped micelles originated from “soft-template” of polyethylene glycol (PEG-800). Besides, ultraviolet–visible spectroscopic (UV-Vis), and photoluminescent (PL) Bi2S3 band features indicated that the nanowires have excellent optical properties, in the optical field of potential applications.
