Simple synthesis method of Bi2S3/CdS quantum dots cosensitized TiO2nanotubes array with enhanced photoelectrochemical and photocatalytic activity

Abstract

A TiO₂ nanotubes array film with nanowires directly formed on top (denoted as TiO₂ NTWs) was prepared by an anodization method (potentiostatic anodization growth). Bi₂S₃ QDs were sensitized on the CdS/TiO₂ NTWs array by a simple successive ionic layer adsorption and reaction (S-SILAR). A short-circuit photocurrent density of 2.16 mA cm⁻² was obtained under an illumination of AM 1.5 G. The data of the photoelectrochemical performance test show that Bi₂S₃/CdS co-modification can boost the photocurrent density of the bare TiO₂ NTWs by up to 308%. The photocatalytic activity was tested by treating rhodamine B (RhB) and methyl orange (MO) solutions, which were degraded completely after 240 min and 210 min, respectively. The present study shows the Bi₂S₃/CdS/TiO₂ NTWs array can be applied in photocatalytic devices, and the greatest advantages are low-cost, easy reuse and recyclability.