▎ 摘　　要

In this study, N-doped grapheme (NG) was synthesized by a hydrothermal method with graphemes oxide (GO) as raw material, melamine (C3H6N6) as reductant and nitrogen source. Results indicated that the nitrogen atoms have been effectively embedded into graphene when the composition mass ratio of GO:C3H6N6 was 3:1. After that, the NG was saturated with Au@Pt core-shell nanoparticles (Au@Pt NPs), which prepared by seed-mediated growth method, to obtain N-doped Au@Pt core-shell nanoparticles (NG-Au@Pt NPs). Then, the NG-Au@Pt NPs was dropped on Au electrode to construct an electrochemical sensor (NG-Au@Pt NPs/Au electrode) for sensing catechin. The electrochemical behaviors on modified electrode of catechin were investigated in detail at desired different conditions. The electrochemical sensor for catechin determination showed an excellent response and exhibited a wide linear range of 1.0 x 10(-7)-4.5 x 10(-5) M with the detection limit of 2.85 x 10(-9) M. The recovery range and the precision relative standard deviation were 99.94-101.5% and 0.06-1.5% for determination of catechin in teas, respectively, indicating that the proposed method was expeditious and reasonable for catechin determination.