Amino-functionalized multilayer Ti3C2Tx enabled electrochemical sensor for simultaneous determination of Cd2+ and Pb2+ in food samples

Herein, amino-functionalized multilayer titanium carbide (NH2-Ti3C2Tx) was developed and applied to electrochemical sensor for simultaneous determination of Cd2+ and Pb2+. The NH2-Ti3C2Tx was prepared by grafting (3-amino-propyl) triethylsilane (APTES) onto the surface of Ti3C2Tx. Its morphology, crystal structure and chemical composition were characterized by field emission scanning electron microscope (FESEM), X-ray diffractometer (XRD), and X-ray photoelectron spectroscopy (XPS). Benefiting from the unique multilayer structure, large active surface area, strong adsorption capacity and excellent electrical conductivity, the functionalized NH2-Ti3C2Tx presented satisfactory electrochemical performances for Cd2+ and Pb2+ determination, and the detection limits were 0.41 μg L-1 and 0.31 μg L-1, respectively. Based on chemical coordination and electrochemical accumulation, the suggested mechanism for Cd2+ and Pb2+ determination was also deeply clarified. Besides, it was successfully applied to simultaneous determination of Cd2+ and Pb2+ in food samples including rice, wheat, sorghum and corn, demonstrating a good practicability.