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

Abstract

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.

In situ construction of core–shell structured cobalt oxide@nickel–cobalt-layered double hydroxide nanorods with abundant oxygen vacancies towards boosting electrochemical energy storage

“…Notably, the electric double-layer capacitance value ( C dl ) of the NCLO electrode (539 mF cm −2 ) is significantly higher than that of the NCL electrode (333 mF cm −2 ), demonstrating that the oxygen vacancies present in the electrode cause a larger density of active sites per unit area. 41,42 To investigate the rate capability, the specific capacitance of the four samples was calculated (Fig. 4f).…”