Synthesis, electrochemical, and photophysical studies of hexadecachlorinatedphthalocyaninato zinc(II)

Synthesis of a new symmetrical 1,4,8,11,15,18,22,25-octahexyloxy-2,3,9,10, 16,17,23,24-octa-(3,5-dichlorophenyl)phthalocyaninato zinc(II), ZnPc, has been described and characterized by ¹H NMR, ¹³C NMR, MS, UV-Vis, and IR spectrometry. The newly prepared ZnPc is soluble in organic solvents and is not aggregated in solution. The photophysical properties were studied by steady-state absorption and emission, cyclic voltammetry, and nanosecond transient absorption techniques. The prepared ZnPc absorbs and emits at longer wavelengths compared to that of reported phthalocyanine derivatives. The electron-donating properties of the ZnPc have been examined by mixing it with the electron-accepting dicyanoperylene-3,4,9,10-bis(dicarboximide), PDICN₂. The recorded nanosecond transient spectra in the visible/near-IR region showed clearly the electron-transfer from the triplet-excited state of the ZnPc to PDICN₂ with a rate of 3.40 × 10⁸ M^-1 s^-1. Light absorption in a wide section of the solar spectrum, favorable redox properties, and the electron-transfer properties suggest usefulness of the ZnPc in light-energy harvesting and developing optoelectronic devices.