Substituents role in zinc phthalocyanine derivatives used as dye-sensitized solar cells. A theoretical study using Density Functional Theory

Plot ΔGinject versus sum of the Hammett parameters of the substituents on the ligand R. To quantize the effect of substituent in the peripheral of the phthalocyanine of zinc, we plotted the ΔGinject (associate to Q band) versus sum of the Hammett parameters (Σσ). A linear response with r2 = 0.93 is obtained. These results suggest new dyes for solar cells, based on molecules with adequate absorption bands using the appropriate substituent.