Hollow zinc phthalocyanine nanoshells: quick low temperature synthesis, enhanced near-IR absorption and water-dispersibility for photocatalysis and phototherapy

Abstract

A quick (two minutes), low temperature (10 °C) synthesis has been developed to obtain crystalline and hollow zinc phthalocyanine (ZnPc) nanoshells (major axis: 32.0 ± 5.2 nm, aspect ratio: 1.3, void size: 18.1 ± 2.3 nm) with a redshift of the Q-band and emergence of a new NIR peak (746 nm). Thioglycolic acid (TGA)-capping uniquely imparts the ability for it to act as solo photocatalyst which was not found in uncapped ZnPc NPs. In addition, it also exhibited robust photothermal effect (ΔT = 16 °C) under NIR-LED (660 nm) irradiation. The optimum sub-50 nm size also makes them well suited for phototherapy as well.