Branched Bi₂S₃/TiO₂ nano-heterostructure with enhanced photoelectric performance

The fabrication of a branched nano-heterostructure composed of Bi 2 S 3 nanosheet branches and TiO 2 nanorod stem was performed using a facile and cost-effective hydrothermal method. The nanoscale morphology of Bi 2 S 3 deposited on TiO 2 nanorod arrays was regulated by controlling the hydrothermal growth time of Bi 2 S 3 sensitizer. The optical properties and photoelectrochemical performance were evaluated systematically for Bi 2 S 3 /TiO 2 heterostructures with different morphology. The Bi 2 S 3 /TiO 2 heterostructures presented the higher visible-light absorption ability and photoelectric performance compared to the bare TiO 2 . The highest photocurrent density of approximately 6.01 mA cm −2 was obtained for the Bi 2 S 3 /TiO 2 heterostructure with 1 h hydrothermal sensitization time. The improved photoelectric performance was attributed to the unique branched structure resulting in an obviously enhanced light absorption in visible-light region and better electron-hole separation and transporation.