Preparation And Properties Of A Novel Composite Photosensitizer Of The Squarylium Indocyanine Dye

To develop new dye sensitizer with wide spectral response is one of the mostimportant ways to improve the dye sensitized solar cell efficiency. The squaryliumindocyanine dye has been synthesized from squaric acid and the dye intermediatesynthesized by myself. The product was purified by the silica gel column chromatographyand the structure was confirmed by HNMR, ESI-MS and IR.Based on this, the further application of the squarylium indocyanine dye was studied,including the squarylium indocyanine dye-p-aminoazobenzene derivative synthesizedfrom the squarylium indocyanine dye and the p-aminoazobenzene, the compositephotosensitizer got from the squarylium indocyanine dye and the p-aminoazobenzene bydifferent mole ratio of them, the graphene modified by the squarylium indocyanine dye,and the squarylium indocyanine dye-oxalic acid compound synthesized from thesquarylium indocyanine dye and the oxalic acid, and the spectral properties of them werestudied.The molar extinction coefficient of squarylium indocyanine dye is more than105L/mol·cm, its maximum absorption wavelength is638.5nm in methanol and occurresblue shift with the increasing of solvents polarity. Squarylium indocyanine dye-p-aminoazobenzene derivative, the composite photosensitizer and the squaryliumindocyanine dye-oxalic acid compound all have strong absorption both in the range of638.5nm and400nm, so the range of absorption spectrum of the squarylium indocyaninedye is broaden. The physical properties of the graphene modified by the squaryliumindocyanine dye, such as dispersion in water, film-forming properties etc. are improved,but the mechanism remains to be further studied.