In-situ synthesizing CoONAl-C catalysts from spent LiCoO2 batteries and tobacco stems biomass: nearly 100 % peroxymonosulfate utilization

Strategic metal recovery from spent lithium-ion batteries (LIBs) is urgently required novel technologies with high efficiency, low environmental impact, and strong economic viability. This study proposes a tobacco stems biomass assisted strategy that directly converts spent LiCoO 2 into advanced functional Co-based catalyst in water treatment. Benefited from the biomass pyrolysis, Co-based catalyst was first in-situ doped with metal (Al) and non-metal (C and N) to obtain CoON Al -C catalysts. The prepared CoON Al -C achieved nearly 100 ​% peroxymonosulfate (PMS) utilization efficiency, which exhibited a persulfate per mass pollutants normalized kinetic rate constant surpassing reported water treatment systems by 2–42 times. The co-doping of metal (Al) and non-metal (C and N) not only shortened the bond length between PMS and Co-O but also upward shifted the d-band center close to Fermi-level. The alteration of Co active sites' electronic distribution via Co-N coordination, combined with loading and reduction of biomass pyrolysis, significantly promoted Co(II)/Co(III) redox cycles. This synergy boosted PMS adsorption-activation and Fenton-like catalytic activity, ultimately driving O-O bond cleavage to generate reactive oxygen species for efficient degradation of emerging contaminants. Moreover, the practical applicability of CoON Al -C was supported by its high stability over seven cycles, minimal ion leaching, reduced toxicity of intermediates, and effective operation in real water samples. This study addressed the high PMS consumption bottleneck in water treatment, contributing to the sustainable utilization of spent LIBs and waste biomass. • CoON Al -C was in-situ synthesized from spent LiCoO 2 cathodes and tobacco biomass. • CoON Al -C exhibited nearly 100 ​% PMS utilization to degrade carbamazepine completely. • PMS/mass pollutants normalized k surpassed reported systems by 2–42 times. • CoON Al -C shorten the bond length with PMS and modified the d-band center. • CoON Al -C showed great cyclic stability, pH tolerance, and anti-interference.