Publications (2)9.74 Total impact
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Article: Porphyrin sensitizers with π-extended pull units for dye-sensitized solar cells.
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ABSTRACT: New π-extended porphyrin dyes with long alkoxyl chains at the ortho positions of the meso-phenyls, and meta di-tert-butylphenyl-substituted porphyrins , and were synthesized for dye-sensitized solar cells, and their optical, electrochemical and photovoltaic properties were investigated and compared with those of and . The absorption spectra of showed a slight red shift of Soret bands and blue shift of Q bands as compared to the meta-substituted porphyrins due to the electron-donating effects of dioctyloxy substituents at the ortho-positions of the meso-phenyl rings. Replacement of the carboxyl with a cyanoacrylic acid as the anchoring group results in significant broadening and red shifts of the absorptions, which is due to the strong electronic coupling between the pull unit and the porphyrin ring facilitated by the C[triple bond, length as m-dash]C triple bond. The electrochemical studies and quantum-chemical calculations (DFT) indicated that the ortho alkoxy-substituted sensitizers exhibit lower oxidation potential, i.e. a higher HOMO energy level, and their HOMO-LUMO gaps are comparable to the meta-substituted analogues. The photovoltaic measurements confirmed that the ortho-octyloxy groups in the two meso-phenyls of and play a significant role in preventing dye aggregation thereby enhancing the corresponding short-circuit current density and open-circuit voltage. The power conversion efficiency (η) of is 8.04%, which is 11% higher than that of , whereas the efficiency of is 6.03%, which is 135% higher than that of . On the other hand, the poor performance of and is due to the floppy structural nature and limited molecular rigidity of the cyanoacrylic acid anchor.Physical Chemistry Chemical Physics 04/2013; · 3.57 Impact Factor -
Article: Design and characterization of alkoxy-wrapped push-pull porphyrins for dye-sensitized solar cells.
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ABSTRACT: Three alkoxy-wrapped push-pull porphyrins were designed and synthesized for dye-sensitized solar cell (DSSC) applications. Spectral, electrochemical, photovoltaic and electrochemical impedance spectroscopy properties of these porphyrin sensitizers were well investigated to provide evidence for the molecular design.Chemical Communications 03/2012; 48(36):4368-70. · 6.17 Impact Factor
