Upcycling spent ternary lithium-ion batteries into enlarged covalency manganese-based Fenton-like catalysts for efficient emerging contaminants removal.

Abstract

Growing deployment of ternary Mn-rich lithium-ion batteries (LIBs) for electric vehicles generates large amounts of spent ternary Mn-rich LIBs. However, traditional recycling processes face limited economic benefit because of the high-content but low-value Mn. Upcycling Mn from them into Fenton-like catalysts is a promising strategy, but their activity is limited by the thermodynamic constraints of Mn(II)/Mn(III)/Mn(IV) redox cycling. Herein, we proposed an upcycling process to convert them into Mn-based Fenton-like catalysts (MnNiCoO_x-LIBs) for efficient emerging contaminants removal by peroxymonosulfate (PMS) activation. Co-doping with strong-electronegativity Ni/Co from spent ternary Mn-rich LIBs enlarges Mn-O covalency in MnNiCoO_x-LIBs, strengthening PMS adsorption and breaking the thermodynamic limitation of Mn(IV)/Mn(III) redox cycling by PMS. As expected, the Fenton-like activity for bisphenol A removal of MnNiCoO_x-LIBs is 3.3 times that of MnO_x prepared from commercial oxalates. It exhibits excellent anti-interference ability, long-term stability (over 800 min), and universality for multiple emerging contaminants. Life cycle assessment confirms that MnNiCoO_x-LIBs shows superior environmental sustainability and cost-effectiveness. Notably, multiple spent ternary Mn-rich LIBs can be upcycled into MnNiCoO_x-LIBs that exhibit lower synthetic cost and better Fenton-like activity than multiple reported catalysts. This work provides a promising approach for emerging contaminants removal and sustainable recycling of spent ternary Mn-rich LIBs.