Photosensitization of TiO2 nanorods with CdS quantum dots for photovoltaic devices

CdS quantum dots (QDs) coated TiO2 nanorod arrays have been prepared via a two-step method. TiO2 nanorod arrays were synthesized by a facile hydrothermal method, and CdS QDs were deposited on the nanorods by a sequential chemical bath deposition (S-CBD) technique. The surface morphology, structure, optical and photoelectrochemical behaviors of the core-shell nanorod array films are considered. A photocurrent of 2.5 mA/cm2, an open circuit photovoltage of 1.10 V, and a conversion efficiency of 1.91% were obtained under an illumination of 100 mW/cm2, when the CdS QDs deposited on TiO2 nanorods film for about 7 cycles. The results demonstrate that the composite films are of excellence with respect to photovoltaic conversion.