Sustainable upcycling of ABS plastic waste into nanostructured carbon for lithium-ion battery applications

Abstract

Acrylonitrile butadiene styrene (ABS), a high-performance thermoplastic widely used in electronics and 3D printing filaments, contributes significantly to the plastic waste problem due to its non-biodegradability. At the same time, the global push toward portable electronics and large-scale renewable energy storage systems has generated unprecedented demand for high-performance lithium-ion batteries (LIBs). We propose a way to convert ABS plastic waste directly from 3D printing scraps and failed prints into nanostructured carbon anodes for LIBs, valorizing a waste stream that is otherwise landfilled or downcycled. We systematically explored and compared the efficiency of our synthetic route, an acid-assisted route involving H2SO4 cross-linking prior to pyrolysis, with that of the conventional method. The addition of sulfonic groups (–SO3H) to the polymer structure stabilized the structure during heat treatment and promoted partial graphitization and the creation of a disordered porous structure. As a result, the carbon yield via cross-linking reached 30.13%, which is 6 times higher than that yielded by bare ABS. Structural characterization confirmed an expanded interlayer spacing of 3.7 Å, the presence of nanoscale graphitic domains, and a defect-rich microstructure, which are characteristics favorable for Li+ intercalation. In terms of electrochemical performance, the anode demonstrated a reversible capacity of more than 300 mAh g−1 in the first cycle, which was retained even after 100 cycles with a coulombic efficiency of 98%. It maintained excellent performance even at −15 °C. This work demonstrates that ABS plastic waste—one of the fastest-growing plastics in the 3D printing industry—can be directly converted into high-performance anode materials for lithium-ion batteries, offering a practical route for diverting this waste stream toward a valuable end use. A full assessment of the process's environmental footprint (chemical and energy inputs and wastewater generation) is needed before establishing its broader sustainability relative to the processes using conventional carbon sources.