Ni3V2O8 Nanosheets Grafted on 3D Helical-shaped Carbon Nanocoils as A Binder-free Hierarchical Composite for Efficient Non-enzymatic Glucose Sensing

High fabrication cost, chemical instability, and complex immobilization of enzyme molecules are critical issues of enzyme-based glucose sensors. Designing state-of-the-art, binder-free, and non-enzymatic glucose sensing probes plays an imperative role to cope with the aforementioned issues. 3D carbonaceous nanomaterials coated with transition metal vanadates (TMVs) are a favorable biomimetic platform for glucose quantification. Peculiar hierarchical structure, enhanced conductivity, synergistic interaction, multiple oxidation states, and high catalytic activity would make such composite a potential contender for non-enzymatic glucose sensing. Herein, 3D helical-shaped carbon nanocoils (CNCs) are grown on nickel foam (NF) via chemical vapor deposition method to prepare a robust CNCs/NF scaffold. Then, a hydrothermal route is followed to grow interconnected free-standing Ni₃V₂O₈ nanosheets (NSs) on CNCs/NF scaffold. This novel and binder-free Ni₃V₂O₈ NSs/CNCs/NF hierarchical composite possesses superior electrochemical active area (ECSA) and exceptional electrochemical efficacy. Amperometric analysis exhibits extremely prompt detection time (0.1 s), elevated sensitivity (5214 µA mM⁻¹ cm⁻²), and low detection limit (0.04 µM). Developed sensor demonstrates appreciable recoveries (93.3 to 103.3%) regarding glucose concentration in human serum. The appealing analytical results show that deployment of a 3D helical-shaped hierarchical smart scaffold can be an effective strategy for developing efficient and advanced non-enzymatic glucose sensors.