Recent advances and prospects in MOF/MXene sensors

Abstract

Two-dimensional transition metal carbides (MXenes) have attracted considerable attention owing to their unique structures and high dielectric losses. To improve the electron transfer ability of electrodes with poor conductivity, highly conductive materials have been incorporated into the surfaces of electrodes modified with metal–organic frameworks (MOFs). Compared to pure metals, MXenes and MOFs exhibit similarly high conductivities while offering enhanced dispersion in multipolar solvents and broader tunability. Titanium carbide (Ti3C2Tx) is a representative MXene with numerous exposed functional groups on its surface, including hydroxyl, O, and fluorine groups. These functional groups attach to semiconductor materials via electrostatic interactions or H bonds, endowing the supramolecular assembly of MOFs and Ti3C2Tx with high conductivity at the macro level. The resistance variations in MOF/Ti3C2Tx are reflected in the formation of Schottky junctions, which provide a host platform for MOFs. This review provides an evaluation of the latest research frontiers in the MOF/MXene direction by categorizing the sensors based on their target detection. Moreover, the design principles and working mechanisms of previously reported MOF/MXene detection sensors are summarized and the design features adopted to address the difficulties in synthesis are described. Finally, the challenges and future development prospects in this field are discussed.