▎ 摘　　要

Polyvinylpyrrolidone-stabilized graphene(PVP-graphene) was synthesized and investigated as a modifier for the determination of ascorbic acid(AA). With PVP acting as stabilizer and dispersant, the resulting PVP-graphene material could disperse well into water. And the PVP-graphene modified glassy carbon electrode(PVP-graphene-GCE) showed an obvious electrocatalytical activity toward the oxidation of AA in a phosphate buffer solution(PBS, pH=7.0) with an oxidation potential of AA at 0.052 V vs. Ag vertical bar AgCl(sat. KCl). The calibration curve for AA was linear in a concentration range from 1.0x10(-5) to 5.0x10(-4) mol/L with a correlation coefficient of 0.9998. And the detection limit was found to be 1 mu mol/L. During the oxidation of AA, the pi-pi interaction of graphene plane with conjugated hexenoic acid-lactone in AA molecules might play a key role. As a result, an obvious decrease of overpotential was achieved at such a PVP-graphene electrode through a possible adsorption/enrichment process, which will probably trigger potential applications for the electroanalysis of some aromatic and heterocyclic compounds.