Solid-phase photocatalytic degradation of polystyrene plastic under visible light irradiation by graphitic carbon nitride nanosheets

Abstract

In recent years, the production of polystyrene has increased in scale to satisfy rising demand. Therefore, a significant amount of polystyrene waste is still produced, along with related environmental and health issues. Under the influence of visible light irradiation, this study examined the solid-phase photocatalytic degradation of polystyrene (PS) plastic using graphitic carbon nitride nanosheets (CNs) in the surrounding air. The CNs were synthesized and characterized, and their surfaces were examined. Different techniques were used to investigate the CNs' efficacy as photocatalysts after they were combined with polystyrene to create a homogeneous blend. The techniques included monitoring the changes in weight loss, depression in molecular weight, and surface morphology following irradiation. The main byproducts of the effective breakdown of PS-CNs composite plastic are water and CO2. After 50 h of exposure to visible light, the PS-CNs (8 wt %) film lost 10 % of its weight. Additionally, irradiated polystyrene containing CNs showed the greatest amount of surface alterations, including the formation of cracks, roughness, and dark spots. A plausible mechanism was objectively provided based on proof and was in good agreement with the data gathered. According to the current study, polymer-CNs compositing is a viable and feasible method of decomposing plastic waste in the presence of visible light without causing any pollution.