1 Tetrachelate Porphyrin Chromophores for Metal Oxide Semiconductor Sensi tization: Effect of the Spacer Leng th and Anchoring Group Position Speaker :李李李 Jonathan Rochford, Dorothy Chu, Anders Hagfeldt, and Elena Gal oppini J. Am. Chem. Soc. 2007, 129, 4655 -4665
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1 Tetrachelate Porphyrin Chromophores for Metal Oxide Semiconductor Sensitization: Effect of the Spacer Length and Anchoring Group Position Speaker :李光凡.
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Tetrachelate Porphyrin Chromophores for Metal Oxide Semiconductor Sensitization: Effect of the Spacer Length and Anchoring Gro
up Position
Speaker:李光凡
Jonathan Rochford, Dorothy Chu, Anders Hagfeldt, and Elena Galoppini
J. Am. Chem. Soc. 2007, 129, 4655 -4665
2
Photoinduced Electron Transfer from Molecules to Semiconductor Nanopar
ticles
Lian, T. Coord. Chem. Rev. 2004, 248, 1231.
3
Different Ways of Anchoring Molecules on Surfaces
Grätzel, M. Coord. Chem. Rev. 1998, 177, 347
4
Structures of Dyes
Durrant, J. R. J. Am. Chem. Soc. 2004, 126, 5225.
5
Work Principle of DSSCs
Grätzel, M. Inorg. Chem. 2005, 44, 6841.
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“Rigid-rod” and “Tripodal”
J. Phys. Chem. B, 2004, 108, 16642-16653
J. Phys. Chem. B, 2006 110, 15735
J. AM. CHEM. SOC. 2002, 124, 7801-7811
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Structures of The Porphyrins
Sanders, J. J. Chem.Soc. Chem. Commun. 1991, 575.-[E]-[A]-[S]
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Synthesis of the Porphyrin Sensitizers
O
O
N
N
Cl
Cl
2,3-dichloro-5,6-dicyanoquinonert 12h
22-30%
86-92%
68-82%68-76%
rt 12h
rt 3 days
rt 3h
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Synthesis of 4a
Sonogashira coupling reaction
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FT-IR-ATR Spectra of p-ZnTCPP and m-ZnTCPP
v(C=O)
v(C-O)
asymmetric v(CO2-)symmetric v(CO2
-)
v(C=O)
symmetric v(CO2-)
N+- H bending
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FT-IR-ATR Spectra of m-ZnTCP2P and m-ZnTC(PEP)P
v(C=O) v(C=O)
v(C-O) v(C-
O)
asymmetric v(CO2-)
v(C=O)
symmetric v(CO2-)
v(C≡C)
N+-H bending
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12
Main Binding Modes of The Carboxylate Group to TiO2
η1- κ2- μ2-
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Solution UV-Vis Absorption and Fluorescence Emission Data
• Four para- and meta-Zn(II) tetra(carboxyphenyl)porphyrins were studied in solution and bound to metal oxide (TiO2, ZnO, and ZrO2) nanoparticle films to determine the effect of the spacer length and anchoring group position on their photoelectrochemical and photophysical properties.
• All studies indicated that only p-ZnTCPP aggregated, suggesting close packing of the dye molecules on the semiconductor surface, and aggregation effects were not observed for the meta porphyrins.
• The greater efficiency of the rigid planar meta-substituted systems was explained in terms of a greater charge injection into the TiO2 semiconductor from rings that lie flat, and closer, to the surface.