▎ 摘　　要

Bimetallic catalyst has attracted considerable attention due to the higher catalytic activity and better stability than monometallic. In this paper, different Au@Ni bimetallic structures decorated graphene oxide were prepared by adjusting the mass ratio of Au and Ni. A novel sensor based on Au@Ni bimetallic heterodimer (Au@Ni-BHD/rGO) or core-shell (Au@Ni-BCS/rGO) structure was constructed for hydrazine oxidation. The electrocatalytic activity was compared and verified by chronoamperometry, amperometry and cyclic voltammetry. Electrocatalytic active surface area was calculated by Randles-Sevick equation. The electrocatalytic performance of Au@Ni-BHD/rGO modified electrode was investigated and exhibited a low oxidation potential (0.07 V) with two wide linear range from 0.2 mu M to 1 mM and 1 mM to 9 mM for sensing hydrazine with a low detection limit of 0.06 mu M. Likewise, Au@Ni-BCS/rGO modified electrode towards the addition of hydrazine also showed a lower oxidation potential (0 V) with two wide linear range from 3 mu M to 1 mM and 1 mM to 20 mM, and a low detection limit of 0.9 mu M. Moreover, both of the modified electrodes offered high selectivity, good reproducibility and stability. This study demonstrates a promising sensing material for electrochemical detection of hydrazine and a new idea for the development of other sensors.