Study On Antibacterial Action And Precious Metals Capture Of Two-Dimentional Graphdiyne Nanocomposites

A variety of pathogens exist in human living environment,which have posed great threat to human life and health.Obviously,antimicrobials have played significant roles in fighting against pathogens.Of the various antimicrobials that effectively combat pathogens,carbon nanomaterials work well due to their excellent antibacterial properties.As an emerging two-dimensional carbon nanomaterial,graphdiynes?GDY?that own fascinating structures have drawn broad attention in the fields of energy storage,optics,catalysis,etc.However,the use of GDY and its derivatives in the antibacterial fields was rarely reported.Herein,the antibacterial actions of GDY and graphdiyne oxide?GDYO?were studied systematically,as a result owing to its special morphology and surface functional groups,GDYO was endowed with higher antibacterial activity than GDY.Also antibacterial mechanism of GDYO against Escherichia coli and Staphylococcus aureus was revealed.In our subsequent study,the capture of precious metal ions by GDY and GDYO was studied.It was found that GDY and GDYO could selectively adsorb precious metal ions from aqueous solution and in-situ reduce them into nanoparticles simultaneously.Finally,the feasibility of the use of the recovered precious metals as antibacterials was confirmed.First,GDYO was synthesized via an oxidation treatment on GDY with H₂O₂/H₂SO₄ as the oxidants.After the morphology and structure identifications,GDY and GDYO show a two-dimensional layered morphology with wrinkle on surfaces.As expected,there are a large number of negatively charged groups on the surface of GDYO,such as-OH,-COOH,C-O-C,etc.Subsequently,the antibacterial activities of GDY and GDYO were examined by the assistance of a series of antibacterial tests.Whether in dark or under the light irradiation,GDYO had higher antibacterial activity than GDY,and the light irradiation could improve the antibacterial efficiency of GDYO.The turbidity and stability tests evidenced that the oxygen-containing functional groups on the surface of GDYO made it more dispersive in water,which endows GDYO higher bacteria-killig activity than GDY.Next GDY and GDYO were employed as trapping agents to recover precious metal ionz(e.g.,Au³⁺,Ag⁺,and Pd²⁺)under different pH values and interference ions.Both GDY and GDYO show high recovery toward Au³⁺,Ag⁺,and Pd²⁺ions under strong acidity.Additionally,the superparamagnetic Fe₃O₄ nanoparticles were deposited on the surface of GDY and GDYO,which made recovery of precious metals by GDY and GDYO more efficient and convenient due to the magnetic response of Fe₃O₄ nanoparticles.Then,the antibacterial activity of the as-captured precious metals against Escherichia coli and Staphylococcus aureus were confirmed,demonstrating the feasibility of recovery of precious metal for antibacterial reuse was confirmed.This work provides a new idea for the development of GDY and its derivatives,and poses great scientific significance and practical application in the recovery and reuse of precious metals.