Fabrication of CdSe/CdTe Quantum Dots Co-Sensitized TiO2 Nanorods by Electrochemical Atomic Layer Deposition Method

Abstract

In this paper, uniformly distributed CdSe and CdTe quantum dots (QDs) are deposited simultaneously on the surface of TiO2 nanorods via electrochemical atomic layer deposition (ECALD) method. XRD and TEM characterization confirm that the deposits are the composite of CdSe and CdTe QDs. SEM observation presents that the co-sensitized QDs cover homogenously both on the top and side surface of TiO2 nanorods, and the EDX composition analysis suggests that the ratio of Cd to Se and Cd to Te is approximate 1:1, indicating that ECALD can control the deposition of each element well. In comparison with the CdSe or CdTe QDs sensitized photoanodes, the photo absorption range of the CdSe/CdTe co-sensitized QDs photoande is greatly broadened, and a power conversion efficiency of 2.01% with a short-circuit current density of 6.59 mA/cm2 at AM 1.5 solar light of 100 mW/cm2 is achieved for the CdSe/CdTe QDs co-sensitized solar cells.