Synergistic effects of CNT-bridged dual-phase MoS2 on MXene as a ternary hybrid electrode for rapid sensing of chloramphenicol in aqueous media

• Hierarchical electrode was fabricated by integrating layered MoS 2 and bridged CNTs on staked MXene via hydrothermal process. • The synergistic effect of MoS 2 and CNT bridging improves the electrical conductivity and network stability. • This hierarchical heterostructure imposes a high selectivity toward sensing chloramphenicol (CAP). • Developed sensor was demonstrated to achieve a high sensitivity of 14.22 μA nM −1 cm −2 . • The CNT/MoS 2 /MXene sensor practicability was evaluated with milk, eye drops, and pork samples. The fabrication of a hybridized electrochemical sensor denoted CNT/MoS 2 /MXene for chloramphenicol (CAP) detection is described based on growing MoS 2 nanoflakes on stacked Ti 3 C 2 T x MXene and bridging the structure obtained with carbon nanotubes (CNTs). Herein, we introduce an acid-etched stacked Ti 3 C 2 T x MXene as an interlayered structure to accommodate solvothermally grown layered MoS 2 and a bridged CNT network for the efficient electrocatalytic sensing of CAP. The successful growth of MoS 2 on the MXene surface prevented restacking of layered MXene and increased conductivity. Interconnected CNTs over the MoS 2 nanoflake array served as an electron transport highway, accelerating the electron transport pathway and maintaining the structural stability of the MXene/MoS 2 heterostructure. Morphologically, CNT/MoS 2 /MXene was found to have a functionalized multilayered structure and to have a greater electron transfer rate, and a larger electrochemically active surface area than the binary feature. Modifying the surface area of MXene with MoS 2 and CNTs synergistically enhanced the transportation of kinetic barrier electrons and well-defined the redox cycle in the ferricyanide system. Further, the electrochemical detection of CAP using a CNT/MoS 2 /MXene electrode by cyclic voltammetry (CV) produced greater electrochemical responses than bare GCE, MXene, CNT-MoS 2 , and MoS 2 -MXene. In addition, scanning rates, the effects of different concentrations, and pH electrolyte tests showed that the GCE-CNT/MoS 2 /MXene electrode was suitable for the electrochemical sensing of CAP. Amperometric response, as determined by i-t profiles, showed the CNT/MoS 2 /MXene electrode had superior electrochemical sensing performance for CAP detection, a wide linear range (8 to 152 nM), a remarkably low detection limit (0.32 nM), a high sensitivity of 14.22 μA nM −1 cm −2 , and superior stability (96 % activity retention after four weeks). The synergistic effect of the ternary three-dimensional assembly with CNT bridging over hierarchical MoS 2 /MXene increased surface-active sites and electron transportation rates and enhanced CAP detection performance. Moreover, the proposed sensor demonstrated high selectivity and satisfactory recovery for milk, eye drops, and pork.