Three-dimensional Graphene Platelet Synthesis On The Anodized316L Stainless Steel And Its Application In Electrochemical Biosensor

Electrochemical sensor has been widely used in analysis due to its excellentselectivity, high sensitivity, quick response and simple operation. Graphene, atwo-dimensional sheet of a hexagonal network of sp2bonds carbon atoms, has attractedmuch attention owing to the potential application for electrode material inelectrochemical sensor. To improve the electrochemical property of the sensor, athree-dimensional graphene platelet has been prepared on the template of anodized AISI316L stainless steel in this paper. The main contents include:1. The316L stainless steel template was prepared by anodic oxidation in NaH2PO4electrolyte. The results showed that the concentration of NaH2PO4, temperature ofelectrolyte, applied potential and the reaction time had a significant influence on themorphology of anodic stainless steel. In0.3M NaH2PO4electrolyte,30V voltage and0℃, after10minutes of anodic time, a porous structure with a pore size of200nm wasassembled on stainless steel.2. Through hydrothermal method in glucose solution, carbon nanospheres werefabricated on the porous template. The concentration of glucose solution has no obviouseffect on the carbon nanospheres. The grain size decreased with the lower hydrothermaltemperature and the shorter hydrothermal time.3. Three-dimensional graphene platelet was successfully fabricated on anodicstainless steel by dopamine polymerization and polydopamine carbonization. Thephysicochemical characterizations of the graphene platelet were studied by SEM, TEM,XPS and Raman. And the electrochemical behavior was investigated by CV and DPV.The results showed that three-dimensional multilayer graphene with a thickness of14nm, had enlarged the density of exposed edge plane and exhibited excellentelectrochemical activity. The electrochemical sensor based on three-dimensionalgraphene platelet decreased the overpotentials and increased the voltammetric resolution of UA and AA. The large peak separations between UA and AA (0.24V)allowed simultaneous analysis through DPV technique. The sensor could detect0.05-2.0mM AA in the presence of0.1mM UA and5-500μM UAin the presence of1mMAA.