“Dry” NiCo₂O₄ nanorods for electrochemical non-enzymatic glucose sensing

A rod-like NiCo₂O₄ modified glassy carbon electrode was fabricated and used for non-enzymatic glucose sensing. The NiCo₂O₄ was prepared by a facile hydrothermal reaction and subsequently treated in a commercial microwave oven to eliminate the residual water introduced during the hydrothermal procedure. Structural analysis showed that there was no significant structural alteration before and after microwave treatment. The elimination of water residuals was confirmed by the stoichiometric ratio change by using element analysis. The microwave treated NiCo₂O₄ (M-NiCo₂O₄) showed excellent performance as a glucose sensor (sensitivity 431.29 µA·mmol/L⁻¹·cm⁻²). The sensing performance decreases dramatically by soaking the M-NiCo₂O₄ in water. This result indicates that the introduction of residual water during hydrothermal process strongly affects the electrochemical performance and microwave pre-treatment is crucial for better sensory performance.