A new study by Penn State researchers demonstrates that waste polyethylene terephthalate (PET) plastic can be transformed into high-quality synthetic graphite suitable for battery applications. The team converted shredded PET bottles into highly ordered graphitic structures through a thermal process enhanced with graphene oxide additives. The resulting material exhibited larger and more ordered crystallites than those found in commercial natural graphite, indicating potential for superior performance as anode material in lithium-ion batteries.
Published in Diamond and Related Materials, the research addresses dual challenges: the growing demand for battery-grade graphite and the low recycling rates of PET plastic. According to the National Association for PET Container Resources, PET is one of the most widely used plastics globally, yet much of it is downcycled or landfilled despite recycling efforts. Graphite, classified as a critical mineral by the U.S. Department of Energy, is essential for storing and releasing electrical charge in lithium-ion cells used in electric vehicles, consumer electronics and grid-scale energy storage systems.
Lead author Shakshi Sekar, a doctoral student in Penn State’s Department of Energy and Mineral Engineering, explained that adding 2.5% graphene oxide by weight optimized the quality of the synthetic graphite. Oxygen-containing functional groups on graphene oxide sheets serve as templates, promoting lateral growth of graphite crystals during graphitization without introducing metal impurities. This contrasts with traditional methods that use metal catalysts—such as iron, nickel or cobalt—that can leave behind contaminants requiring additional purification.
By avoiding metal catalysts, the process simplifies manufacturing steps and reduces environmental impact. The research was supported by the U.S. National Science Foundation. The team’s approach could be scaled to convert common plastic waste into valuable battery materials, supporting clean energy technologies and redefining plastic recycling as a resource recovery strategy rather than a disposal problem.
Penn State professor Randy Vander Wal, co-author and faculty member in the Institute of Energy and the Environment, noted that further work is needed to assess large-scale production and battery performance. However, the study provides a promising pathway for integrating circular economy principles into the battery supply chain by transforming a prevalent waste stream into high-value, energy storage materials.
Source: Diamond and Related Materials
