Hexadecachloro-substituted lanthanide(III) phthalocyaninates and their hybrid conjugates with gold nanoparticles: Synthesis and optical properties

Abstract Novel hexadecachloro-substituted Eu, Er and Lu monophthalocyaninates were prepared via two alternative ways: lanthanide ion templated tetramerization of tetrachlorophthalonitrile and metallation of the corresponding phthalocyanine ligand. Target complexes were identified by mass spectrometry and fourier transform infrared spectroscopy. Aggregation behavior of these compounds was investigated using UV–Vis and fluorescence spectroscopy. Hybrid nanoparticle conjugates composed of the gold cores (20 and 30 nm in diameter) covered by the layers of target phthalocyanines were obtained. The formation of phthalocyanine shell on the surface of nanoparticles and its elemental composition were examined using transmission electron microscopy experiments. Reverse saturable absorption effect was found in solution of the erbium complex utilizing z-scan technique. Furthermore, significant increase in the effect was observed in hybrid nanoparticles due to their plasmonic properties.