Fabrication and characterization of Sb-doped MXene prepared by hydrothermal method for use as a sensing electrode for heavy metal detection

MXene, a two-dimensional material with favorable physicochemical characteristics, has demonstrated outstanding efficiency in a wide range of applications because of their superior properties, such as higher surface area and conductivity, and facile surface modification. In this study, antimony (Sb) doped MXenes were synthesized via a simple hydrothermal method, employing various Sb concentrations ranging from 5%w/w to 25%w/w. The successful preparation of the Sb-doped MXene (Sb@MXene) was confirmed by an X-ray diffraction (XRD) method. Physical morphologies examined through field-emission scanning electron microscopy (FE-SEM) depict the presence of Sb nanoparticles with the size of about 80 nm on the surface and interlayer of MXenes. The Sb@MXene composites demonstrated significant potential as electrochemical sensing materials for heavy metal detection. Both 5%Sb@MXene and 25%Sb@MXene composites were prepared as the screen-printed electrode (SPE) materials via drop-casting method to sense Pb2+, Cd2+, and Zn2+. The 25%Sb@MXene SPE show the highest sensitivity toward Pb2+(3.62 μA∙ppm‒1), Cd2+(2.53 μA∙ppm‒1), and Zn2+ (0.90 μA∙ppm‒1) solution, compared with that of 5%Sb@MXene SPE. This work not only demonstrates a simple preparation of Sb@MXene, but also applies the hybrid materials in electrochemical sensing application.