Upgrading Polyolefin Plastic Waste into Multifunctional Porous Graphene using Silicone-Assisted Direct Laser Writing

The widespread use of plastics, especially polyolefin including polyethylene and polypropylene, has led to severe environmental crises. Chemical recycling, a promising solution for extracting value from plastic waste, however, is underutilized due to its complexity. Here, a simple approach, silicone-assisted direct laser writing (SA-DLW) is developed, to upgrade polyolefin plastic waste into multifunctional porous graphene, called laser-induced graphene (LIG). This method involves infiltrating polyolefins with silicone, which retards ablation during the DLW process and supplies additional carbon atoms, as confirmed by experimental and molecular dynamic results. A remarkable conversion yield of 38.3% is achieved. The upgraded LIG exhibited a porous structure and high conductivity, which is utilized for the fabrication of diverse energy and electronic devices with commendable performance. Furthermore, the SA-DLW technique is versatile for upgrading plastic waste in various types and forms. Upgrading plastic waste in the form of fabric has significantly simplified pre-treatment. Finally, a wearable flex sensor is fabricated on the non-woven fabric of a discarded medical mask, which is applied for gesture monitoring. This work offers a simple but effective solution to upgrade plastic waste into valuable products, contributing to the mitigation of environmental challenges posed by plastic pollution.