▎ 摘　　要

A new sandwich structure nanocomposite of Ag nanoparticles supported on TiO2-functionalized graphene nanosheet was synthesized, involving a simple chemical reduction of GO using TiCl3 as reducing agent and the in situ formation of TiO2 as linker between r-GO and Ag. Based on the Ag/TiO2/r-GO hybrid material, a novel electrochemical sensor for the determination of nitrite was constructed. The morphology and composition of the nanocomposite were characterized by transmission electron microscope and UV-vis absorption spectra. Electrochemical investigation indicated that Ag/TiO2/r-GO modified electrode exhibited excellent electrocatalytic performance for the oxidation of nitrite. The sensor showed a wide linear range from 1.0 A mu M to 1.1 mM, with the detection limit of 0.4 A mu M, the sensitivity of 112.0 mu A mM(-1) cm(-2). Additionally, the proposed method was successfully applied to the detection of nitrite in water samples with obtained satisfactory results.