Solvent Effect and Spectroscopic Properties of Phthalocyanines in Homogeneous and Micro-Heterogeneous Media
The photophysical and photochemical properties of four commercial phthalocyanines (part A) were investigated in DMSO, DMSO80% / THF20%, DMSO60% / THF40%, DMSO40% / THF60%, DMSO20% / THF80% and THF (v / v). Four phthalocyanines were synthesized (Part B), namely zinc methyl phthalocyanine (MetZnPc), chlorine aluminum methyl phthalocyanine (MetAlClPc), zinc tert-butyl phthalocyanine (TbutZnPc) and chloro-aluminum tert-butyl phthalocyanine (TbutCl ). Their photophysical and photochemical properties were also studied in different solvents, being THF, DMF, DMSO, CHCl3 and MeOH. For the study of life time, the single-photon time correlated technique (TCSPC) was used. In commercial phthalocyanines, the indirect method using DPBF was used to demonstrate the generation of reactive oxygen species of the compounds. The direct method, which analyzes the singlet oxygen phosphorescence decay curves at 1270 nm, was also employed for both commercial and synthesized phthalocyanines. The influence of the central metal on photophysical, photochemical and solvent effect were discussed in all studied compounds, both part A and part B. For the synthesized compounds, the study of the aggregation effect was investigated in THF. The effect of peripheral and axial ligands was verified, as well as the effect of complexed metals on all studied properties.