Engineering Bi2S3/BiOI p-n heterojunction to sensitize TiO2 nanotube arrays photoelectrodes for highly efficient solar cells and photocatalysts

Abstract

Abstract To significantly improve the solar harvesting and electron transportation, Bi 2 S 3 /BiOI p-n heterojunctions were successfully formed on the surface of TiO 2 nanotube arrays (TiO 2 NTs/Bi 2 S 3 -BiOI) by a simple solvothermal method, and the morphology, composition and photoelectrochemical property of the TiO 2 NTs/Bi 2 S 3 -BiOI were investigated by adjusting the concentration ratio of sulphur/iodonium. TiO 2 NTs/Bi 2 S 3 -BiOI nanosheets and nanorods were prepared, and the self-assembled microflowers were also observed. The results indicated that flower-like TiO 2 NTs/Bi 2 S 3 -BiOI showed high visible light absorption, photocurrent density and rapid photoelectrocatalytic removal of organic dyes and Cr(VI). The growth and photocatalytic mechanism were proposed to illuminate the high photoelectrochemical performances. The excellent photoelectrochemical activities drive the TiO 2 NTs/Bi 2 S 3 /BiOI being superior environmental and energy materials in the applications of wastewater purification and solar cells.