Dendritic core-shell copper-nickel alloy@metal oxide for efficient non-enzymatic glucose detection

Abstract

The synergy effect of bimetallic oxide shell and high electrically conductive metallic core enables the dendritic Cu-Ni/ nickel foam (NF) for detecting non-enzymatic glucose. • Binder-free Cu-Ni alloys@metal oxide was prepared by facile electrodeposition method. • The dendritic structure promotes glucose diffusion and provides rich active sites. • The bimetallic oxide shell and metallic core enable highly effective glucose sensing. A success has been achieved in the synthesis of dendritic core-shell copper-nickel alloy@metal oxide on nickel foam (Cu-Ni/NF) electrode for non-enzymatic glucose detection by going through a facile electrodeposition process followed by oxidation in NaOH solution. The direct electrodeposition approach facilitates the transfer of electrons in the binder-free electrode, and the dendritic structure promotes glucose diffusion while providing sufficient active sites required for the process of glucose electrocatlysis. Moreover, the unique core-shell structure promotes the catalytic activity towards glucose oxidation due to the synergistic effect caused by the bimetallic oxide shell and the metallic core that is conductive to electron transport. Accordingly, the Cu-Ni/NF electrode exhibits a high sensitivity of 11.34 mA mM −1 cm -2 , a low detection limit of 2 μM (S/N = 3), and a wide linear range of 1–600 μM for glucose detection. In addition, the electrode demonstrates such advantages as high selectivity, fast response time, and long duration stability. The designed Cu-Ni/NF electrode shows its massive potential of application for non-enzymatic glucose detection.