Recycling Microplastics to Fabricate Anodes for Lithium‐Ion Batteries: From Removal of Environmental Troubles via Electrocoagulation to Useful Resources

Abstract Electrocoagulation is an evolving technology for the abatement of a broad range of pollutants in wastewater owing to its flexibility, easy setup, and eco‐friendly nature. Here, environment‐friendly strategies for the separation, retreatment, and utilization of microplastics via electrocoagulation are investigated. The findings show that the flocs generated by forming Fe₃O₄ on the surface of polyethylene (PE) particles are easily separated using a magnetic force with high efficiency of 98.4%. In the photodegradation of the obtained flocs, it is confirmed that Fe₃O₄ shall be removed for the efficient generation of free radicals, leading to the highly efficient photolysis of PE. The removed Fe₃O₄ can be recycled into iron‐oxalate compounds, which can be used in battery applications. In addition, it is suggested that heat treatment of Fe₃O₄–PE flocs in an Ar atmosphere leads to forming Fe₃O₄ core–carbon shell nanoparticles, which show excellent performance as anodes in lithium‐ion batteries. The proposed composite exhibits an excellent capacity of 1123 mAh g⁻¹ at the current density of 0.5 A g⁻¹ after 600 cycles with a negative fading phenomenon. This study offers insight into a new paradigm of recyclable processes, from environmental issues such as microplastics to using energy materials.