Architecting Bi2S3/graphene quantum dots/TiO2 photoelectrodes for aqueous Cr(VI)/methyl orange removal

Abstract Ternary shell/core/core Bi 2 S 3 /graphene quantum dots/TiO 2 nanowire arrays (Bi 2 S 3 /GQDs/TNWs) photoelectrodes are constructed through electrophoretic deposition of GQDs onto TNWs followed by electrochemical deposition of Bi 2 S 3 QDs. An interesting synergistic effect was observed in configuration of Bi 2 S 3 /GQDs/TNWs. Under irradiation, the photocurrent density of 50 μA/cm 2 (an enhancement of ∼86%) and the removal efficiency of Cr (VI) is 97% (an enhancement of ∼76%) compared to that TiO 2 nanowire array were obtained. Such significant enhancement is attributed to the strong photoabsorption ability of Bi 2 S 3 QDs and excellent electron transport ability of GQDs.