A novel Cu-Cu2O hetero-structure for ultrasensitive detection of dopamine

Abstract Herein, Cu-Cu₂O heterostructure were grown in situ on the surface of Cu nanoplates by chemical etching at room temperature. A novel dopamine (DA) electrochemical sensor based on Cu-Cu₂O/glass carbon electrode (Cu-Cu₂O/GCE) was constructed. The Cu-Cu₂O/GCE sensor showed a wide linear range of 0.001 mM to 2 mM and a low limit of detection (LOD) of 7.1 nM (S/N = 3) for DA. The improved performance of the Cu-Cu₂O/GCE is attributed to the special void structure which increases the catalytic active sites and electrochemical active surface areas (ECSA). Besides, the optimization of Cu₂O and Cu ratio effectively regulates the electron configuration of the Cu-Cu₂O heterojunction. The Cu-Cu₂O/GCE sensor also showed good reproducibility, stability, and excellent anti-interference ability.