BODIPY Compounds as Non-Innocent -Spacers for DSSC Dyes

BODIPY Compounds as Non-Innocent -Spacers for DSSC Dyes

Devin D. Machin, Catherine Bonnier, Bryan D. Koivisto*

Science at the Interface August 14, 2012Department of Chemistry and BiologyRyerson University

The Opportunities For Solar TechnologyCrystalline silicon photovoltaics (PVs) dominate the solar technology market They are a mature technology, efficient and robustHowever, they are expensive and have limited design potential.

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Solar energy haspromising potential

The Dye Sensitized Solar Cell (DSSC)3The DSSC is a promising next generation PV technology

1. A photon is absorbed2. The excited e- is injected into TiO23. The e- enters the circuit4. The dye molecule is reduced by the electrolyte

The Dye Molecule4

The dye molecule is the powerhouse of the DSSC

The use of BODIPY and a non-innocent -spacer for DSSC dyes is explored

Organic dyes typically follow a Donor--spacer-Acceptor motifSun, L. et al., J. Org. Chem., 2007, 9550.

Boron-Dipyrromethene (BODIPY) A robust moiety, that is redox stable and therefore can be used to increase the absorption envelope and long-term stability of DSSC dyes.

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Erten-Ela, S. et al., Org. Lett., 2008, 3300. Mau, M. et al., Dyes Pigments., 2012, 231.

Conjugation is interrupted by the orientation of theIndicated phenyl groupIndicated group is a poor electron donorTarget moleculesA family of BODIPY dyes with modified conjugation lengths for red-shifted absorption6

Synthesis of Target 2a & 2b

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2b in DCMFluorescence of BODIPY is quenched through the addition of donor and anchor groups

Synthesis of Target 5a & 5b

85b in DCM

Cyclic Voltammetry and DFT9HOMOLUMO

B3LYP/6-31G

Calibrated vs Ferrocene (not shown)UV-vis Spectra Comparison10

Hagfelt, A. et al., Chem Rev., 2010, 6595. Dyes 2b and 5b show red shifted absorptions tailing off to 630 nmSummary and Future work 6 of 8 target molecules were successfully synthesized.These dye molecules have promising physical properties (UV-vis, CV)11

Dyes will be used in prototype devices to determine conversion efficiencyFuture synthesis utilizing other organic frameworks as non-innocent -spacers

AcknowledgementsCurrent GroupDr. Bryan Koivisto (PI)Dr. Catherine Bonnier (PDF)Devin Machin (BSc)Omar Abdi (BSc)Muhammad Yousaf (MSc)

Left to Right: Devin, Catherine, Bryan, Muhammad, & OmarPeopleFunding

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