Synthesis,Photoelectric Properties And Application Of Metalloporphyrin Dimer/Graphene Composites

Porphyrins and their derivatives have been widely used not only in simulating photosynthesis system,photodynamic therapy,sensors,self-assembly but also in biomedicine,biochemistry,medicinal chemistry and new energy due to their special structure and properties.Particularly,the application of dimer,trimer and poly porphyrin combined with biometrics has attracted more and more attention.Graphene is a new two-dimensional material with many excellent properties,such as extremely thin thickness,high conductivity,high mechanical strength,stable chemical properties and large specific surface area.Therefore,graphene is regarded as both a good carrier material and a modified material which can promote the electron transfer between biomolecules and electrodes.The combination between porphyrin and graphene can simultaneously obtain excellent performance of the two.Effective electron transfer effect between the two can make the complex more excellent photoelectric properties.At present,the complex method of grapheme-porphyrin composites is mainly divided into covalent and noncovalent.We chose noncovalent recombination method to realize porphyrin functionalization in this paper.The results showed that this composite material had satisfactory optical properties and electrocatalytic properties.1.Firstly,two porphyrin dimmers including DP₁ and DP₂ were designed and synthesized.The monomers were 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin.The monomer bridged by trans butenediacyl group is DP₁ and the monomer bridged by 2,6-pyridinedicarbonyl group is DP₂.Then the two porphyrin ligands were coordinated with metal salts respectively.Finally,six kinds of porphyrin metal composites were obtained.The composites were characterized by MS,¹H NMR,UV-Vis and IR spectra and other methods.2.Graphene oxide(GO)was prepared by oxidation of graphite using Hummers method.Metal composites and graphene oxide were stabled by the?-?non covalent interaction.The structures of the composites were characterized via UV-Vis,IR and SEM techniques,which showed that graphene can effectively combine with porphyrin metal complexes.3.The GO-metal porphyrin composites were coated on the electrode surface to prepare metal porphyrin dimer/GO composite electrode.The catalytic reduction performance for oxygen of the composite modified electrode was tested by CV,which illustrated that composites had excellent electrocatalytic activity for oxygen reduction.The photocatalytic degradation of organic dyestuff methylene blue by composites were studied,showing that the composites owned more satisfactory photocatalytic activity in the degradation of methylene blue solution in comparison with porphyrin metal complexes.