Julien Warnan

Panchromatic trichromophoric sensitizer for dye-sensitized solar cells using antenna effect.

The first trichromophoric sensitizer, consisting of covalently linked boradiazaindacene (BODIPY), zinc porphyrin (ZnP), and squaraine (SQ) units, has been synthesized by Heck alkynylation to obtain a panchromatic dye, for dye sensitized solar cells (DSSCs). Efficient intramolecular energy transfers (ET) were observed between all chromophoric subunits and enhance the overall conversion efficiency by 25%. The antenna effect is demonstrated by the photoaction spectrum which features all of a chromophores absorption bands.

Diketopyrrolopyrrole-zinc porphyrin, a tuned panchromatic association for dye-sensitized solar cells

Aiming at collecting a maximum amount of energy with one panchromatic sensitizer, three novel dyes based on zinc porphyrin and diketopyrrolopyrrole units have been synthesized. Suitable dye functionalization resulted in a very broad coverage of the solar spectrum and an efficient photovoltaic energy conversion reaching 7.74% in a DSC device.

Bio-inspired artificial light-harvesting antennas for enhancement of solar energy capture in dye-sensitized solar cells

Light absorption is the primary step in any photovoltaic device, therefore panchromatic light collection is a fundamental condition to maximize the efficiency of a solar cell. Indeed, the photocurrent density is directly proportional to the fraction of the light absorbed by the cell relative to the whole incoming solar flux. By mimicking the light harvesting antennas of natural photosynthetic systems it is possible to enhance the light capture of photoanodes in DSCs by using different absorbing units which funnel the incident light to the sensitizer by energy transfer. In this perspective article, bio-inspired strategies to improve the light collection efficiency of dye-sensitized solar cells (DSCs) by the antenna effect are reviewed. We provide a summary of some of the most important and recent developments in the utilization of the antenna effect to improve the photocurrent density in DSCs. This article highlights how new and innovative multi-chromophoric sensitizers can effectively broaden and enhance the absorption cross-section which enables us to produce higher photocurrent density both in liquid and solid state solar cells. The potential for development, future challenges and opportunities of this strategy are discussed.

Application of Poly(3‐hexylthiophene) Functionalized with an Anchoring Group in Dye‐sensitized Solar Cells

A series of three poly(3-hexylthiophene) functionalized either with a cyanoacetic acid (CA) or a rhodanine-3-acetic acid anchoring groups were synthesized and characterized. The TiO(2) based dye-sensitized solar cells have been fabricated and performances were tested. We show that shorter chain length (15 thiophene units) linked to CA binding group gives good performances as J(sc) , V(oc) , FF and η(%) were 6.93(mA · cm(-2) ), 0.65(V), 0.67 and 3.02%, respectively. A maximum IPCE of ≈50% at 500 nm was recorded with a liquid electrolyte, under AM 1.5 simulated solar irradiance.