Bimetallic NiCo Metal-Organic Framework-Derived Hierarchical Spinel NiCo2O4 Microflowers for Efficient Non-Enzymatic Glucose Sensing

Abstract Hierarchical spinel NiCo2O4 microflowers have been successfully designed and synthesized by a successive mild spray-thermal treatment method via bimetallic NiCo-metal-organic framework formation. Remarkably, NiCo2O4 microflowers can serve as a novel and efficient electrocatalytic active material, showing excellent performance for a non-enzymatic glucose sensor. The obtained NiCo2O4 flower-like structure is composed of two-dimensional nanosheets, and the nanosheet surface is fully exposed to facilitate the diffusion of electrolyte. In the glucose sensing system, the NiCo2O4 microflower-modified glassy carbon electrode exhibits a wide detection range from 0.001 mM to 7.8 mM, a low detection limit of 0.48 µM and a fast response time (3 s). Furthermore, the non-enzymatic glucose sensor shows a considerable anti-interference ability and long-term stability. This work opens up an avenue for the synthesis of hierarchical bimetallic microflower material by a mild spray-thermal treatment method, which also provides a promising strategy for the real-time glucose sensing.