Synthesis and 0.88 μm near-infrared electroluminescence properties of a soluble chloroindium phthalocyanine

A chloroindium phthalocyanine bearing phenoxyl substituents was synthesized and characterized by MS, 1H NMR and elemental analysis, which were consistent with the proposed structure; UV–vis absorption and photoluminescence (PL) spectra were also investigated. Near-infrared (NIR) organic light-emitting devices (OLEDs) were fabricated employing tris-(8-hydroxyquinoline) aluminum (Alq3) and poly(vinylcarbazole) (PVK) which had been doped with chloroindium phthalocyanine. Room-temperature electroluminescence (EL) was observed near 0.88 μm due to transitions from the first excited singlet state to the ground state (S1–S0). As phthalocyanine possesses excellent solubility in common organic solvents, the light-emitting layer can be prepared by spin coating to simplify the fabrication process and so lower the manufacturing costs. The emission processes of this chloroindium phthalocyanine in the doped devices are discussed.