Highly sensitive glucose sensor based on hierarchical CuO

The fabrication of high performance CuO based glucose sensors remains a great challenge due to the “trade-off effect” between sensitivity and linear range. In this study, a hierarchical CuO nanostructure with a great number of firecracker-shaped nanorods along the ligament and three-dimensional interconnected nanoporous is obtained by dealloying and post oxidation process of Al-33.3 wt% Cu eutectic alloy ribbons. Because of the precise structural design, not only the number of active sites for glucose electro-oxidation is significantly increased but also the glucose diffusion under high concentration is greatly accelerated, leading to a high sensitivity of 1.18 mA cm⁻² mM⁻¹ and a wider linear range up to 5.53 mM for glucose detection. This work provides a potential approach to design hierarchical nanostructure for other metal oxides with desirable properties for electrocatalytic applications.