Preparation and Optical Properties of Spherical Bi2S3 Nanoparticles by In Situ Thermal Sulfuration Method
Spherical Bi 2 S 3 nanoparticles (NPs) were prepared by a facile in situ thermal sulfuration method. Different Bi 2 S 3 samples were obtained by controlling the sulfuration time. The products were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), Raman and Fourier-transform infrared (FT-IR) methods. The optical properties were examined by UV-visible-near-infrared (UV-Vis–NIR) and photoluminescence (PL) techniques. The results show that the phase of the products after sulfuration is pure and the spherical shape of Bi NPs has been successfully transmitted to Bi 2 S 3 samples. The light absorption edges exhibit red shift to 1060 nm while the light emission displays blue shift to 868 nm, compared with the energy bandgap of bulk Bi 2 S 3. The reason for the special optical properties of Bi 2 S 3 NPs by this in situ sulfuration route is considered to associate with the defects and quantum size effect of NPs.