Synthesis of monodispersed ultrafine Bi2S3 nanocrystals

Monodispersed ultrafine Bi2S3 nanocrystals of ∼3 nm were synthesized via a facile and mild method, in which thioacetamide and bismuth oleate complex were used as the sulfur and bismuth precursors, respectively. The obtained Bi2S3 nanocrystals possessed a high surface area of 305 m2 g−1. The nanostructures of Bi2S3 nanocrystals were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and selective area electron diffraction (SAED) techniques. The optical property of the Bi2S3 nanocrystals was studied by photoluminescence spectroscopy. A remarkable blue shift and a band gap of ∼1.5 eV were observed. The shape of the Bi2S3 nanocrystals could be tuned by adjusting the initial Bi/S molar ratio and reaction temperature, respectively. A possible burst nucleation mechanism for this monodispersed ultrafine Bi2S3 nanocrystals was proposed.

► Monodispersed and ultrafine Bi2S3 single-crystals with size of ∼3 nm were successfully synthesized under a facile and mild condition. ► A remarkable blue shift and a band gap of ∼1.5 eV were observed. ► A possible burst nucleation mechanism for the formation of the monodispersed and ultrafine Bi2S3 nanocrystals is proposed.