Enhancement of photocatalytic degradation of polyethylene plastic with CuPc modified TiO2 photocatalyst under solar light irradiation

Solid-phase photocatalytic degradation of polyethylene (PE) plastic, one of the most common commercial plastic, over copper phthalocyanine (CuPc) modified TiO2 (TiO2/CuPc) photocatalyst was investigated in the ambient air under solar light irradiation. Higher PE weight loss rate, greater texture change; more amount of generated CO2, which is the main product of the photocatalytic degradation of the composite PEC plastic can be achieved in the system of PE–(TiO2/CuPc) in comparison with PE–TiO2 system. The CuPc promoted charge separation of TiO2 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 TiO2 or TiO2/CuPc particle surfaces play important roles. The present study demonstrates that the combination of polymer plastic with TiO2/CuPc composite photocatalyst in the form of thin film is a practical and useful way to photodegrade plastic contaminants under solar light irradiation.