Performance enhancement of CdS-sensitized TiO 2 mesoporous electrode with two different sizes of CdS nanoparticles

Abstract

In order to absorb broad spectrum and enhance the absorption in visible region, a novel electrode architecture is designed to co-sensitize TiO 2 mesoporous film with two different sizes of CdS nanoparticles. Firstly, an added layer of CdS film with large size CdS nanoparticles (L-CdS) is coated on the TiO 2 mesoporous film using spin-coating technique. Then the small size CdS nanoparticles (S-CdS) are deposited on TiO 2/L-CdS mesoporous film by sequential chemical bath deposition method. The co-sensitization electrode (TiO 2/L-CdS/S-CdS electrode) shows enhancement and broadening of absorption spectrum, in comparison with single-sensitization electrodes (TiO 2/L-CdS and TiO 2/S-CdS electrodes). The conversion efficiency of the semiconductor-sensitized solar cells (SSSCs) prepared with TiO 2/L-CdS/S-CdS electrode is 1.60% which is higher than that of the SSSCs prepared with TiO 2/L-CdS and TiO 2/S-CdS electrodes.