MXene-Based Nanostructured Materials for Gas Sensing Applications

Abstract

MXenes, discovered in 2011, are group of two-dimensional (2D) transition metal (M) carbides, nitrides and carbonitrides. These are synthesized by the removal of the A layer from MAX phases, where M represents a transition metal, A denotes an A-group element (like aluminum, gallium or silicon) and X represents carbon or nitrogen. MXenes exhibit exceptional properties like high electrical conductivity, hydrophilicity and impressive mechanical strength. These properties position them as highly promising candidates for a variety of applications including gas sensing, energy storage and catalysis. Regarding gas sensing, MXenes have demonstrated remarkable performance dependent on the aspect ratio, large surface area and strong surface reactivity. Gas sensors based on MXenes demonstrate high sensitivity and selectivity towards various hazardous gases and volatile organic compounds. The sensitivity of MXenes arises due to their extended surface area, demonstrating ameliorated gas sensing capability and exceptionally rich surface terminations that facilitate gas detection, adsorption and detection capability. Moreover, the tunable electrical conductivity due to the alterable surface terminations and doping facilitate ameliorated gas sensing ability. These MXenes, when interacting with gas molecules, undergo modifications in their electronic structure, conductivity or optical properties. Additionally, the mechanical stability of these MXenes is an additional advantage for their real-world application. The present book chapter provides a detailed overview regarding current trends in the field of MXene development and the future outlook in the field of MXene synthesis.