Preparation Of Graphene Oxide-manganese Porphyrin Complex And The Research Of Its Catalytic Performance

Metalloporphyrin compounds have attracted great attention due to their similarly functions to the P450 enzyme and high catalytic activity.However,the metalloporphyrin monomers are susceptible to self-oxidation in the homogeneous reaction and destroy their structures,resulting in a decrease in catalytic activity,and they are also difficult to recycle.Therefore,immobilizing of metalloporphyrins on organic or inorganic materials is gathering much attention in the research field.Graphene can serve as a good carrier carbon material.The porphyrin-graphene oxide composite can combine the excellent properties of both by attach metal porphyrins to graphene oxide with covalent bonds.The analysis by UV,FT-IR and SEM showed that the graphene oxide and porphyrin were bound together by the amide group.Compared with the non-covalent bonding method,the covalently bound compound GO-MnTAPP is more stable.The obtained composite material was modified on a glassy carbon electrode and applied to the study of electrocatalytic oxygen reduction reaction(ORR).It can be found that the composite has good catalytic performance,and has a high stability and sensitivity.In order to improve the catalytic activity and stability of graphene oxide-metalloporphyrin complexes,we further prepared metalloporphyrin conjugated polymers-graphene oxide complexes.Using CuI/N,N-dimethyglycine as the catalyst system,the amino manganese metal porphyrin immobilized on the surface of graphene oxide is bridged with p-dibromobenzene to form metal porphyrin polymer(GMPP-AMP).Characterization of complexes of graphene oxide-metal porphyrin polymers.Using this polymer as a catalyst,the reaction of sulfoxide catalyzed oxidation to sulfoxide under mild conditions was investigated.The GMPP-AMP was applied to the study of catalytic oxidation of sulfide compounds.Through the investigation of the reaction conditions such as reaction time,the amount of isobutyraldehyde and catalyst input in the process of catalytic oxidation.The results showed that phenyl sulfide was used as the reaction substrate,toluene was the solvent,and isobutylaldehyde was the aids,the conversion of thioanisole was as high as 98%and the selectivity was 99%for 1 h at 50 ~oC.The catalyst was applied to the catalytic oxidation of other thioether compounds,all exhibiting a good catalytic effect.At the same time,studies on the recycling of catalysts show that the catalyst exhibits good stability and is easy to recycle and reuse,and the possible catalytic mechanism was proposed.Finally,we modified the GMPP-AMP to a glassy carbon electrode and further examined the electrocatalytic reduction of the polymer to nitrobenzene.The Cyclic Voltammetry(CV)shows that the GMPP-AMP polymer has good electrocatalytic activity for nitrobenzene.The low concentration of nitrobenzene was detected by differential pulse Voltammetry(DPV).The results showed that the concentration of nitrobenzene has a good linear relationship with the peak of the reduction current in the range of 0.04 mM-0.24 mM.This indicates that the polymer-modified electrode has good potential for the detection of nitrobenzene and has high stability and sensitivity.