Reaction time dependent investigation on the properties of the Bi 2 S 3 nanoparticles: Photocatalytic application

Abstract Different morphologies of the Bi 2 S 3 nanostructures (nanorods and nanoparticles) were successfully synthesized with a facile reflux method with small reaction time (10 min, 20 min and 30 min) at 120°C. The morphology was transformed from nanorods to nanoparticles when the reaction time is increased. The effect of reaction time on the morphology, particle size, band gap and photocatalytic performance of the Bi 2 S 3 products have been investigated. The Bi 2 S 3 nanostructures have been formed with bismuth nitrate and thiourea as starting reactants, ethylene glycol as the reaction medium and polyvinylpyrrolidone (PVP) as the structure-directing reagent. The obtained products are characterized by Powder X-Ray Diffraction, SEM, EDAX, UV-Vis Spectroscopy and FT-IR. XRD patterns show that the Bi 2 S 3 nanoparticles obtained are of orthorhombic structure. The Scanning electron microscopic images confirm the formation of nanoparticles. The results of the energy dispersive analysis of X-ray (EDAX), UV-Visible spectroscopy (UV-Vis), FT-IR studies are compared and discussed. The photocatalytic activity studies reveal that the synthesized Bi 2 S 3 nanorods exhibit excellent photocatalytic performance in degrading methylene blue dye solution under UV irradiation.