Size-controlled synthesis of Cu2O nanoparticles on reduced graphene oxide sheets and their application as non-enzymatic glucose sensor materials

Abstract

Cuprous oxide nanoparticles uniformly dispersed on reduced graphene oxide (RGO) sheets were prepared by a polyol process using copper acetate and graphite oxide as precursors in diethylene glycol solution. The size of Cu2O particles can be controlled by changing the heat treatment time. With prolonging the heat treatment time at 140 °C from 0 to 30 min, the size of Cu2O particles on the reduced graphene oxide sheets decreases from 500 to 4 nm. The electrochemical activity of the Cu2O/RGO composites in potassium ferricyanide solution shows strongly sensitive on the size of Cu2O nanoparticles. Moreover, the smallest size of composite-based electrode shows excellent electrochemical activities for electrocatalytic oxidation of glucose in alkaline medium. The proposed biosensor can be applied to the quantification of glucose with a high sensitivity and durability, wide linear range, a low detection limit of 0.1 μM, and ease of construction, thus is promising for the future development of non-enzymatic glucose sensors.