Cu2O–Au nanocomposites for enzyme-free glucose sensing with enhanced performances

Abstract

A facile method for the synthesis of Cu2O–Au nanocomposites has been reported by injecting Cu2O nanocubes into Au precursor directly with the assistance of ultrasound radiation at room temperature. The ultrasound radiation is not a necessary requirement but can make the distribution of Au nanoparticles more homogenous. The formation of Cu2O–Au nanocomposites is attributed to following two reasons. The first one is the difference in the reduction potential between Cu2+/Cu2O and AuCl4−/Au, which can also be considered as the driving force for the redox reaction. The other one is the low lattice mismatch between (200) planes of Cu2O and (200) facets of Au, which is favorable for the formation of heterostructure. The electrochemical investigation demonstrates that the performances of Cu2O nanocubes in enzyme-free glucose sensing have been improved significantly after the decoration of Au nanoparticles which may be derived from the polarization effect provided by Au nanoparticles. As-prepared Cu2O–Au nanocomposites have great potential in enzyme-free glucose sensing.