Comparative study between dye-sensitized and CdS quantum-dots-sensitized TiO 2 solar cells using Photoinduced absorption spectroscopy

Abstract

Two 8μm thick TiO 2 photoelectrodes have been sensitized separately by N719 dye molecules and CdS quantum dots for a comparison study. Photoinduced absorption (PIA) spectroscopy was employed to investigate the mechanistic properties of electrons under illumination conditions comparable to sunlight. The PIA spectrum of both electrodes (in the presence of electrolyte) is due to electrons in TiO 2 and iodine radicals I 2 -. in the electrolyte. In the absence of redox electrolyte, both electrodes show long-lived photoinduced charge-separation with lifetime in a millisecond range (8.5ms for Q-dot-sensitized TiO 2 and 11.5ms for dye-sensitized TiO 2). Copyright © 2011 Idriss Bedja and Anders Hagfeldt.