Enhancement of photocatalytic degradation of polyethylene plastic with CuPc modified TiO 2 photocatalyst under solar light irradiation

Abstract

Solid-phase photocatalytic degradation of polyethylene (PE) plastic, one of the most common commercial plastic, over copper phthalocyanine (CuPc) modified TiO 2 (TiO 2/CuPc) photocatalyst was investigated in the ambient air under solar light irradiation. Higher PE weight loss rate, greater texture change; more amount of generated CO 2, which is the main product of the photocatalytic degradation of the composite PEC plastic can be achieved in the system of PE–(TiO 2/CuPc) in comparison with PE–TiO 2 system. The CuPc promoted charge separation of TiO 2 and enhanced the photocatalytic degradation of PE based on the analysis of surface photovoltage spectroscopy (SPS). During the photodegradation of PE plastic, the reactive oxygen species generated on TiO 2 or TiO 2/CuPc particle surfaces play important roles. The present study demonstrates that the combination of polymer plastic with TiO 2/CuPc composite photocatalyst in the form of thin film is a practical and useful way to photodegrade plastic contaminants under solar light irradiation.