Enhancing enzyme-free glucose detection with three-dimensional NiCo2O4 nanowire arrays wrapped with NiCo2O4 nanosheets

Incorporating a secondary metal and engineering heterogeneous nanostructures can significantly enhance the electrochemical performance of non-enzymatic glucose sensors. Herein, NiCo 2 O 4 nanowire (NW) arrays were enveloped with NiCo 2 O 4 nanosheets (NSs) using a simple hydrothermal method. NSs improved the electronic conductivity of NW arrays, while arrays prevented the aggregation of NSs, resulting in exceptional glucose sensing performance. In 0.1 mol·L −1 NaOH electrolyte, this composite electrode demonstrated remarkable sensitivity (7641 µA·mmol −1 ·L·cm −2 ), broad linear detection range (1 to 1250 µmol·L −1 ), low detection limit (0.16 µmol·L −1 ), and rapid response time (within 1 s), as well as excellent selectivity, reproducibility, and stability. Such a unique architecture of NiCo 2 O 4 NW arrays enhanced the specific surface area of the composite material, facilitating the efficient electron transfer between copper foam and NiCo 2 O 4 NSs. This work provides an economical and efficient approach for developing enzyme-free glucose sensing catalysts with superior electrochemical properties.