State of the art recent progress in two dimensional MXenes based gas sensors and biosensors: A comprehensive review

Recently, MXenes have emerged as a novel and fast-growing family of two dimensional (2D) materials. This broad group of 2D materials is of significant scientific and technological importance and has drawn tremendous attention from diverse scientific fields due to its unique surface chemistry, graphene-like morphology, metallic conductivity, high hydrophilicity, good mechanical properties and redox capability. MXenes have created a large impact on the research communities through novel technological advances and the tremendous application potential in various research fields especially in gas sensing and biosensing due to their 2D structure, unique compositions, adsorption characteristics and the possibility to tailor the surface properties via surface functionalization. In this review, the synthesis, structure, surface chemistry and properties of MXenes have been discussed. This review mainly focuses on the state of the art recent advancements in gas sensing, biosensing and piezoresistive sensing applications of MXenes. The sensing properties of various types of MXene derivatives have been reviewed based on different categories of sensors namely solid-state gas sensors, electrochemical biosensors, and piezoresistive wearable sensors. The review also outlines the current challenges and future research perspectives for fostering advanced and high-performance MXenes based sensors. The main purpose of the present review is to get acquainted with the sensing properties of MXenes and the recent developments in this rising research field.