Enhancing Electrochemical Sensing via Hybridization of 2-D Mxene and Transition Metal Dichalcogenides

The exceptional conductive properties, flexibility, and surface functionality of two-dimensional (2D) transition-metal carbides/nitrides (MXenes) position them as prospective electronic materials for electronic devices and electrochemical sensors specifically. Nonetheless, strategies to amplify MXene's sensitivity to volatile organic compounds (VOCs) in particular remain relatively uncharted. In this study, we elucidate a novel methodology involving surface treatment and exfoliation to fabricate a hybrid material of 2D WSe2 and Ti3C2Tx.<br/>By employing scanning electron microscopy, transmission electron microscopy, X-ray diffractometry, and dynamic light scattering, we characterised the microstructure, size, and surface charge states (zeta potential) of WSe2 and Ti3C2Tx nanosheets. This extensive analysis facilitated the optimal processing of the WSe2 and Ti3C2Tx hybrid, enabling its use as ink for ink-jet printing of flexible Ti3C2Tx/WSe2 electrochemical sensors, which are integrated into wireless systems.<br/>VOCs were selected as the test subject to elucidate the functional properties of these 2D nanohybrids for electrochemical sensing. Within this configuration, the Ti3C2Tx scaffold contributes high electrical conductivity while the WSe2 nanoflakes impart remarkable sensitivity and enhanced selectivity to VOCs.<br/>Contrasted with other Ti3C2Tx reference sensors and 2D materials-based sensors, the Ti3C2Tx/WSe2 sensors exhibit superior resilience after numerous bending cycles. They also demonstrate exceptional electrochemical durability and sustained response, with distinct selectivity for detecting model VOCs (ethanol, methanol, acetone, hexane, benzene and toluene) across a broad concentration range (1–40 ppm) at room temperature.<br/>This work is expected to illuminate a path for future exploration into the hybridization of 2D MXenes, paving the way for the creation of high-performance electrochemical sensing devices.