A Highly Efficient Fiber‐Shaped Non‐Enzymatic Glucose Sensor Based on Nickel‐Modified Anodic TiO 2 Nanotubes

Rational electrode architecture design is critical for enhancing the performance of non‐enzymatic electrochemical glucose sensors, yet efficient utilization of redox‐active sites in flexible and miniaturized platforms remains difficult. Herein, we report a fiber‐shaped Ni@CTNT electrode fabricated on a Ti wire via a sequential anodization–carbonization–electrodeposition strategy, where nickel‐based redox centers are integrally coupled with a conductive carbon‐coated TiO 2 nanotube scaffold in a binder‐free configuration. Structural and spectroscopic analyses indicate that Ni is predominantly present as Ni 2+ species, serving as the electroactive precursor for the reversible Ni(OH) 2 /NiOOH redox couple, while the defect‐enriched carbon interface and ordered nanotubular framework provide continuous electron‐transport pathways and strong anchoring of active phases. As a result, the Ni@CTNT electrode delivers a rapid amperometric response (<2 s) and high sensitivity (4624 μA·mM −1 ·cm −2 ) over a practical linear range (0.01–5.78 mM) and enables reliable glucose quantification in a commercial beverage sample. More broadly, this study elucidates an interface and architecture engineering principle in which Ni‐based redox centers are integrated into a conductive and mechanically robust scaffold, thereby enhancing redox‐site utilization and signal reliability and providing a general materials–architecture strategy applicable to other transition‐metal‐based sensing and electrocatalytic systems.