Photocatalytic properties of semiconductor SnO2/CdS heterostructure nanocrystals

Abstract

Here we report the photocatalytic properties of semiconductor SnO₂/CdS heterostructure nanocrystals. A type-II SnO₂/CdS heterostructure has been synthesized from a single-source precursor and its structure was determined using XRD, HRTEM, elemental mapping and line scan EDAX analysis. A time resolved spectroscopic study revealed the effective charge separation in this heterostructure and the mechanism of charge separation was proposed using a schematic model. It is important to mention that the conductivity was found to be lower in the SnO₂/CdS heterostructure compared to uncoated SnO₂ nanorods due to efficient charge separation. The efficient charge separation in the SnO₂/CdS heterostructure revealed its higher photocatalytic activity and the photocatalytic degradation of Congo red dye was found to be 97% and 20% for the SnO₂/CdS heterostructure and SnO₂ respectively under UV light irradiation.