Applied Surface Science, Vol.476, 539-551, 2019
Molten salt conversion of polyethylene terephthalate waste into graphene nanostructures with high surface area and ultra-high electrical conductivity
The pollution caused by the accumulation of plastic products is a serious emerging threat to the nature and to us. Here, we first report on the structural and thermokinetic characterization of the plastic bottle material. It was found that the pyrolysis of polyethylene terephthalate in air leads to the formation of an amourphose carbon with an exceptional thermal oxidation resistance, based on which an effective and scalable molten salt strategy for green conversion of plastic bottles into a highly conducive nanostructured carbon is proposed. In this process, no complicated equipment or protective gas is required. The nanostructured carbon consisted of crystalline graphitic nanosheets with a thickness of less than 10 nm; and an ultra-high electrical conductivity of 1150 S m(-1) at a low bulk density of 1 g cm(-3), with an estimated production cost about US $6 kg(-1). These characteristics are attractive for various applications including conducive additives to electronic devices. In the light of the fact that the plastic pollution crisis cannot be appropriately resolved without the involvement of short term economic motivations, the proposed molten salt method may provide a sufficient economic driving force towards the use of PET wastes as valuable raw materials, hence protecting the environment.