Trash to treasure: Converting plastic waste into a useful graphene foil

Recycling of plastic waste has commercial value and practical significance for both environmental safety and recovery of resources. To realize trash recycling, a cheap, simple, and safe solid-state chemical vapor deposition method has been developed to convert a series of daily plastic wastes to a high quality graphene foil (GF) at a large scale. The GF possesses a high electrical conductivity of 3824 S·cm^-1, which is much higher than that of the conventional free-standing graphene film treated at an extremely high temperature of 2200-2500 °C. Further, the GF can act as various flexible elements such as a free-standing electrode in a foldable lithium-ion battery, which shows stable electrochemical performances. On the other hand, it presents a fast and ultra low-voltage responsivity to be used as a flexible electrothermal heater, which generates a temperature of up to 322.6 °C at a low input voltage of only 5 V. The convenient trash-to-treasure conversion of plastics to GF provides a unique pathway for waste recycling and opens new application possibilities of graphene in various fields.