Determining the locus for photocarrier recombination in dye-sensitized solar cells

Abstract

We present intensity-modulated photocurrent and infrared transmittance measurements on dye-sensitized solar cells based on a mesoporous titania (TiO2) matrix immersed in an iodine-based electrolyte. Under short-circuit conditions, we show that an elementary analysis accurately relates the two measurements. Under open-circuit conditions, infrared transmittance, and photovoltage measurements yield information on the characteristic depth at which electrons recombine with ions (the “locus of recombination”). For one particular series of samples recombination occurred near the substrate supporting the titania film, as opposed to homogeneously throughout the film.

Influence of a TiCl4Treatment Condition on Dye-Sensitized Solar Cells

“…From intensity-modulated infrared spectroscopy, Frank et al concluded that electron recombination near the FTO substrate is an important recombination route. 15) Recently, Yanagida group introduced that the thin Nb 2 O 5 layer works as a remarkable blocking layer at the FTO/TiO 2 interface, obtaining an increased cell performance. 13,16) Our group also investigated the positive effect of the underlayer on the cell performance of metal substrate based DSSC.…”

Photoinduced absorption spectroscopy of dye-sensitized nanostructured TiO2

“…PIA spectroscopy is frequently used in the field of conjugated polymers to investigate the nature and recombination kinetics of photogenerated species [5,6]. Recently, PIA measurements at a single wavelength in the near-infrared (frequency-resolved modulated www.elsevier.com/locate/cplett transmission) have been used to study dye-sensitized solar cells [7,8]. In this Letter we will present PIA spectra for both dye-sensitized solar cells and dye-sensitized TiO 2 films kept in air and determine the recombination rates under varying conditions from the frequency dependence of the PIA signals.…”

Dye Sensitized Solar Cells as an Alternative Approach to the Conventional Photovoltaic Technology Based on Silicon - Recent Developments in the Field and Large Scale Applications

“…Film morphology is a crucial parameter in DSSCs' performance mainly to the influence in electron recombination rate. As referred in literature this phenomenon usually happens in the contact between TiO 2 film and conductive substrate (Zhu, et al, 2002). Therefore, a condensed non-porous thin film of TiO 2 is formed between nanocrystalline thick film and TCO substrate and referred as "blocking layer".…”