Light scattering amplification on dye sensitized solar cells assembled by hollyhock-shaped CdS-TiO 2 composites

Abstract

To investigate the scattering layer effect of a TiO 2 multilayer in dye-sensitized solar cells (DSSCs), we designed a new DSSC system, assembled with a CdS-TiO 2 scattering layer electrode. A high-magnification SEM image exhibited hollyhock-like particles with a width of 1.5-2.0 μm that were aggregated into 10-nm clumps in a hexagonal petal shape. The efficiency was higher in the DSSC assembled with a CdS-TiO 2 scattering layer than in the DSSC assembled with TiO 2-only layers, due to the decreased resistance in electrochemical impedance spectroscopy (EIS). The short-circuit current density (J sc) was increased by approximately 7.26% and the open-circuit voltage (V oc) by 2.44% over the 1.0 wt % CdS-TiO 2 composite scattering layer and the incident photon-to-current conversion efficiency (IPCE) in the maximum peak was also enhanced by about 5.0%, compared to the DSSC assembled without the CdS-TiO 2 scattering layer.