Magnetic velvet-like graphitic carbon nitride (V-g-C 3 N 4 /Fe 3 O 4 ) was used for rapid 1 min extraction of flavonoids from different tea extracts by co-solvent enhanced adsorptive magnetic solid phase extraction . The nanocomposite can interact with flavonoids, in which Fe 3 O 4 provide hydrogen bond and V-g-C 3 N 4 has hydrophobic and π-π interaction to promote adsorption. The enhanced adsorptive magnetic solid phase extraction method is developed with the addition of a co-solvent (water) to dramatically change the solvent environment, which enhanced the speed of movement of target compounds from the solvent to the sorbent and increase the adsorption capacity. The synergistic effects improved the extraction rate of flavonoids with excellent reproducibility (88.2–107.2%), sensitivity (limits of detection (S/N = 3): 0.075–0.1 μg/mL) and recoveries (88.2–107.2%). This study demonstrated the potential to apply this method for various target analytes from complex sample matrices.
Lithium (Li) metal has been considered as a potential substitute for the graphite anode in Li-ion batteries to further boost their energy density. Polymer electrolytes (PEs) are expected to be applied in Li metal batteries (LMB) to replace liquid electrolytes due to safety concerns. Among others, poly(vinylidene fluoride- co -hexafluoropropylene) (PVDF-HFP)-based electrolytes offer clear advantages such as improved processability and chemical/electrochemical stability. However, Li dendrite growth in LMBs and the low Li-ion conductivity of solid polymer electrolytes (SPEs) still hinder their practical applications. To address this issue, it has been proposed that solvent-enhanced PVDF-HFP-based polymer electrolytes (SPPEs) with a tuned amount of residual N -methyl-2-pyrrolidone (NMP) could provide improved ionic conductivity and outstanding chemical/electrochemical stability. We report herein the effects of different salts, polymer, and additives on the electrochemical performance and interface stability of SPPEs. We demonstrate that lithium salts and blended polymers play a pivotal role in the electrochemical performance of SPPEs. In addition, additives exert a remarkable effect on the stripping/plating behaviors of metallic lithium anode in SPPEs. SPPEs with adequate LiNO 3 are found to be stable with lower overpotentials at 0.5 mA cm −2 on cycling of symmetrical Li cells. These results highlight novel SPPE strategies for optimizing the ionic conductivity and stabilizing the lithium metal anodes.
危险品化学品经营许可证（带存储）