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

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 Fe₃ O₄ 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 Fe₃ O₄ shall be removed for the efficient generation of free radicals, leading to the highly efficient photolysis of PE. The removed Fe₃ O₄ can be recycled into iron-oxalate compounds, which can be used in battery applications. In addition, it is suggested that heat treatment of Fe₃ O₄ -PE flocs in an Ar atmosphere leads to forming Fe₃ O₄ 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.