Highly efficient determination of Mn 2+ in Chinese liquor by using a novel electrochemical sensor based on TiO 2 -NH 2 @covalent organic framework nanocomposites.

This study developed an electrochemical sensor for the determination of Mn in Chinese liquor by modifying a glass carbon electrode with TiO-NH@COF, which was synthesized the controllable growth of COF onto the surface of TiO-NH using the Schiff-base condensation reaction between 2,5-dimethoxyterephthalaldehyde and 1,3,5-tris(4-aminophenyl)benzene. The morphological and structural characterization studies of the proposed TiO-NH@COF were carried out by SEM, TEM, HRTEM, EDX, BET, XRD and FTIR techniques. Owing to the excellent properties and the synergism between TiO and COF, the introduction of TiO-NH@COF improved the electrochemical response significantly. By optimizing the experimental parameters, the sensor exhibited good linearity in the range of 0.1-1.0 nM and 0.08-10 μM with a detection limit of 2.83 × 10 M and 9.50 × 10 M, respectively, showing competitive performance for Mn determination. Besides, the proposed sensor was successfully applied to Mn detection in liquor samples, suggesting its practical application performance.