Review of Metal Sulfide-Based MXene Nanocomposites for Environmental Applications, Gas Sensing, Energy Storage, and Photothermal Therapy

Application of nanoparticles (NPs) guides the design of the particle for enhancing specific properties of interest for that particular application. Two-dimensional transition-metal carbides, nitrides, and carbonitrides [also known as MXene nanosheets (NSs)] have attracted interest as an approach for improving the properties of functional materials of NPs. The modification of surface chemistry has frequently been employed to amplify favorable physical and chemical characteristics of MXenes. A straightforward, economical, and remarkably effective technique in this aspect is the implementation of metal sulfide (MS) nanostructures that adhere to MXene NSs through van der Waals interactions. The inherent self-assembly properties of these structures enable simple regulation of the packaging density of the particles. For environmental remediation, properties such as narrow band gap and increased electron and hole transfer make MS/MXene nanocomposites suitable for the degradation and removal of pollutants. For energy applications, the MXene NSs serve as conductive substrates, facilitating fast electron and ion transport, to prevent the aggregation of MS nanostructures. Transition-metal sulfides act as spacers in these designs. In the field of medicine, MS/MXene nanocomposites can be utilized for targeted therapy, for the diagnosis and treatment of cancer, and as antibacterial agents due to their high absorption in the near-infrared region. The present review summarizes the integration of MS/MXene nanocomposites, with a brief discussion of the synthesis and traits of MXenes, along with the progress of various MXene composites, applications of the various NSs, and some of the challenges and future prospects associated with the development of MS/MXene nanocomposites, while highlighting their potential for diverse applications.