Controlled synthesis of bismuth sulfide nanorods by hydrothermal method and their photocatalytic activity

Abstract Bi 2 S 3 nanorods with orthorhombic structure were successfully synthesized through hydrothermal method. Systematic experiments were accomplished to study the variable factors such as the Bi/S molar ratio, reaction time and reaction temperature, which have great impact on the structural morphologies of Bi 2 S 3 and the photocatalytic performance. TEM and FE-SEM images reveal that the prepared Bi 2 S 3 is flower-like built up from many nanorods with average 30–50 nm in diameter and 0.5–1 μm length. The optimal conditions for the preparation of Bi 2 S 3 nanorods were Bi/S molar ratio 1/2 for 20 h at 180 °C to obtain the highest photocatalytic activity of ~ 98% towards methylene blue (MB) degradation. It is also found that the determined k values for Bi 2 S 3 nanorods prepared at Bi/S molar ratio 1/2 was higher 40 and 5.5 times than that the samples prepared at either low or high Bi/S molar ratios 1/0.5 and 1/5, respectively.