Two-Membrane-Pieces Sensitizing Technology and Cyanines Sensitized Nano-TiO2 Materials

Two-membrane-pieces sensitizing method and the corresponding equipments were developed to prepare cyanines sensitized nanoTiO₂ photo anode materials. The cyanines were synthesized from N-p-carboxybenzyl-2,3,3-trimethyl-3H-indoleninium-5-sulfonate potassium and squaric acid or 2-chloro-1-formyl-3-(hydroxymethylene) cyclohex-1-ene. The maximum UV-Vis absorption wavelengths of them were 631 nm and 782 nm, respectively. The nanoTiO₂ thin films were prepared on ITO conductive glass from tetrabutyl titanate by sol-gel technique, and were sensitized with the dyes by two-membrane-pieces dye sensitizing method or immersion sensitizing method. Compared with traditional immersion sensitizing method, two-membrane-pieces sensitizing method was an environmentally friendly and economical process due to less dye consumption and less waste formed.