Sythesis And Electrochemical Sensor Application Of Graphene/Metal Oxide Composites

This article contains four segments. In the first part, we prepared monolayer graphene oxide using a modified Hummers method. Then, graphene was fabricated by taking the green glucose reduction method. Meanwhile, using one step hydrothermal method, graphene-zinc oxide composites with different loading and morphology of zinc oxide were synthesized by adjusting the mass ratio of zinc ion and the graphene in reactant. Finally, the different products were tested.In the second section, the electrochemical detection performances of the different active substances modified glassy carbon electrodes were studied. Under optimal test conditions, the obtained graphene-zinc oxide composite with the reaction mass ratio of 4.4:1 has excellent electrochemical hydrazine sensing performance. The linear response range of the sensor is 1.0 ?M to 33.5 mM, and the detection limit is 0.8 ?M ?S/N= 3?.In the third part, using green hydrothermal one-step reduction method, by adjusting the mass ratio of graphene oxide and copper sulfate pentahydrate in reactant, we prepared the graphene-cuprous oxide composites having different loading and morphology structure of cuprous oxide. Then, the different products were tested.In the final section, by analysis and comparison of the performances of the different active substances modified glassy carbon electrodes, we found that the obtained composite with the reaction mass ratio of 1:80 has excellent electrochemical hydrogen peroxide and glucose sensing activity at the same time. Under optimal electrochemical sensor test conditions, the obtained graphene-cuprous oxide composite with the reaction mass ratio of 1:80 modified glassy carbon electrode has excellent electrochemical hydrogen peroxide sensing performance. The linear response range of the sensor is 0.005 to 2.775 mM, and the detection limit is 0.0108 mM ?S/N= 3?. At the same time, the glucose sensor also has excellent electrochemical performance. The linear response range of the sensor is 0.001 to 0.419 mM, and the detection limit is 7.288×10^-4 mM ?S/N= 3?.