Abstract
The cost-effective upcycling method of waste anode graphite (SG) presents an important challenge within the field of spent lithium-ion battery recycling. In this study, waste graphite was recovered from waste lithium-ion batteries by a one-step mechanochemical method and the high-efficiency graphene-based adsorbent OMG17 was synthesized. Following this, titanium dioxide microspheres (TiO(2)) were integrated through electrostatic self-assembly to create an in situ photo-regeneration adsorbent, referred to as OMG17@TiO(2). The synthesized OMG17@TiO(2) exhibits a well-developed pore structure, characterized by regular crack-like pores and an abundance of functional groups. Furthermore, OMG17@TiO(2) was fabricated into a membrane via the vacuum filtration method, enhancing its practicality for collection in water bodies. The results indicate that the adsorption capacities of OMG17@TiO(2) for methylene blue and rhodamine B reached 673.67 and 966.58 mg/g, respectively, as determined by the Langmuir isothermal model, significantly exceeding the performance of comparable graphitic adsorbents. Additionally, the regeneration efficiency achieved through ultraviolet (UV) irradiation was found to be as high as 70%. In contrast to traditional desorption methods, the in situ photo-regeneration approach offers distinct advantages in preserving the structural integrity of the material, including the maintenance of pore structure and recovery of specific surface area. Through density functional theory calculations and an examination of the adsorption mechanism, it was established that the pore structure and oxygen-containing functional groups are the primary determinants of the adsorption capacity, while the in situ degradation of pollutants within the pores via UV light serves as the principal mechanism for regeneration.