Electrochemical Sensor Based on TiC Membrane Doped with UIO-66-NH for Dopamine

A TiC membrane was prepared by doping UIO-66-NH with TiC through hydrogen bonds. When the doping mass ratio of TiC and UIO-66-NH was 6:1, the electrochemical performance was optimal. Characterization was done by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electrochemical impedance spectroscopy (EIS) which exhibited hierarchical cave-like physiognomy, large specific area, outstanding electronic conductive network, and excellent film-forming property. Moreover, the TiC film was analyzed via atomic force microscopy (AFM), which displayed good mechanical properties and rough surface morphology. The fabricated TiC membrane/GCE sensor was applied to the detection of dopamine (working potential of + 0.264 V vs. Ag/AgCl) with LOD of 0.81 fM and a sensitivity of 14.72 µA fM cm. It was demonstrated that the TiC membrane can be used to construct nonenzymatic sensors with excellent performance. The fabricated sensor has high selectivity and stability and has good practicability with recoveries of 101.2-103.5% and a relative standard deviation (RSD) of 1.2-2.4%.