Recycle graphite from spent lithium-ion batteries for H₂O₂ electrosynthesis

On-site H₂O₂ synthesis via the two-electron route oxygen reduction reaction for environmental remediation is attractive. This work offers a novel strategy for both spent graphite recovery and H₂O₂ electrosynthesis catalyst preparation. The graphite is directly recycled from spent lithium-ion batteries to an H₂O₂ electrosynthesis catalyst. From the view of sustainable development and environmental protection, the H₂O₂ electrosynthesis catalyst prepared using spent graphite is eco-friendly and cost-efficient. The surface functional groups of the recycled graphite are finely tuned by the HNO₃ medium to induce -COOH and C-O-C groups. The activated graphite exhibits high H₂O₂ activity and selectivity, compared to the raw spent graphite. The activated graphite can achieve an H₂O₂ Faradic efficiency of about 80%. The activated graphite has a good prospect for T-acid wastewater treatment as the H₂O₂ generation catalyst. Almost 92% of chemical oxygen demand can be removed.