Strategies to maximize the reuse of electronic and industrial wastes have scientific, economic, social and environmental implications. We herein propose a strategy of “treating waste with waste” using LiCoO 2 cathode powders from spent lithium ion batteries to eliminate industrial pollutants led by sulfur (S) (IV) in waste water. By radical scavenging experiments and electron spin resonance (ESR) analysis, we identified singlet 1 O 2 as the dominant species while SO 4 − and OH as the secondary species for decontamination during the oxidization process mediated by LiCoO 2 powders. The intrinsic mechanism of S(IV) conversion was revealed to be two-step hydrogen migrations from HSO 3 − to O 2 occurring on LiCoO 2 surface by density functional theory (DFT) calculations. The surface of LiCoO 2 powders plays a key role in anchoring sulfur species and forming surface complex as an excellent medium, which is found to be stable and reusable by material characterizations and the recycling experiment. Free Co(II) ions in solvents have no catalysis effect on the conversion of pollutants. Our work offers a particularly vivid example for rational reuse of electronic wastes to eliminate industrial pollutants, and may raise economic benefits in environmental practice due to two aims achieved in once action.
To meet the development of multifunctional surfaces with long-term antibacterial activity for biomaterials and implantable devices, herein, a novel self-polishing antibacterial surface was developed. The functionalized surface was prepared by first surface-initiated ring-opening grafting polymerization (SI-ROP) of a cyclic carbonate monomer 4′-(fluorosulfonyl)benzyl-5-methyl-2-oxo-1,3-dioxane-5-carboxylate (FMC) containing a sulfonyl fluoride group in the side chain onto the material surface and then by a “sulfur(IV)-fluorine” exchange (SuFEx) postclick modification reaction to link the imidazolium salt ionic liquid to the polyFMC (PFMC) brush. In vitro experimental results showed that the functionalized surface has good biocompatibility, enzymatic biodegradable properties and excellent bactericidal properties, which can effectively kill E. coli (∼94%) and S. aureus (∼93%). In addition, the functionalized surface can release the killed bacteria (∼90%) several times efficiently under the action of lipase enzymatic degradation, restoring the original bactericidal function of the surface, thus forming a dynamic self-polishing and self-renewing antibacterial surface. Therefore, this method for the fabrication of self-polishing antibacterial surfaces may offer innovative insights into applications of biomedical implant materials.
Hydrophilic antifouling polymers provide excellent antifouling effects under usual short-term use conditions, but the long-term accumulation of contaminants causes them to lose their antifouling properties. To overcome this drawback, surface-initiated ring-opening graft polymerization (SI-ROP) was performed on the surface of the material by applying the cyclic carbide monomer 4′-(fluorosulfonyl)benzyl-5-methyl-2-oxo-1,3-dioxane-5-carboxylate (FMC), which contains a sulfonylfluoride group on the side chain, followed by a “sulfur(IV)-fluorine exchange” (SuFEx) post click modification reaction to link the hydrophilic polyethylene glycol (PEG) to the polyFMC (PFMC) brush, and a novel antifouling strategy for self-polishing dynamic antifouling surfaces was developed. The experimental results showed that the antifouling surface could effectively prevent the adsorption of proteins such as bovine serum albumin (BSA, ∼96.4%), fibrinogen (Fg, ∼87.8%) and lysozyme (Lyz ∼69.4%) as well as the adhesion of microorganisms such as the bacteria Staphylococcus aureus ( S. aureus ) (∼87.5%) and HeLa cells (∼67.2%). Moreover, the enzymatically self-polished surface still has excellent antifouling properties. Therefore, this modification method has potential applications in the field of biosensors and novel antifouling materials.
危险品化学品经营许可证（带存储）