Recycling Spent Lithium-Ion Battery Cathodes to Multimetallic Phosphides for High-Efficiency Oxygen Evolution Reaction

Surge in lithium-ion battery (LIB) production predicts that massive spent LIBs will be produced in the future. Hence, rational utilization of spent LIBs is a win-win strategy to protect the environment, recycle resources, and reverse the dilemma of the current energy challenges. In this work, different decommissioned layered oxide cathodes were recovered and converted into a novel NiCoMn phosphides–nickel foam (NCM-P) electrode for the OER using acid leaching to extract valuable metals and then carrying out a hydrothermal process and phosphating. The enhanced inherent catalytic activity can be achieved by regulating intermetallic interactions with adjusting the stoichiometric ratio of transition metal. Additionally, the NCM 111-P catalyst obtained from the spent LiNi_0.33Co_0.33Mn_0.33O₂ cathode has a special nanosheet–nanoneedle hierarchical structure, resulting in abundant active sites and stimulative detachment of gases in the OER course. Consequently, the NCM 111-P exhibits competitive catalytic performance (overpotential of 277 mV at 10 mA cm^–2, electrolytic durability of 246 h). The research furnishes a positive way to recycle spent LIBs and promotes the development of electrolytic water.