Overview of MXene-based sensors: Fundamentals and applications in gas sensors, biosensors, and mechanical sensors

MXenes, a class of 2D nanomaterials, have attracted widespread attention due to their exceptional electrical conductivity, large surface area, abundant functional groups, and tunable electronic structure, making them ideal for sensing applications. This review systematically summarizes the latest advancements in MXenes, encompassing widely accepted synthesis methods, key physicochemical characteristics, solution-processing strategies, and their applications in gas sensors, biosensors, and strain sensors. Moreover, we analyze the design principles of synthetic MXenes and derivatives based on the requirements of sensors in various fields, focusing on their intrinsic properties. In addition, we elucidate the underlying mechanisms by which MXenes function in different types of sensors and contribute to their enhanced performance. The incorporation of MXene materials brings synergistic and complementary benefits, significantly improving the sensitivity, selectivity, and stability of MXene-based sensors. Finally, this review highlights ongoing challenges and provides an outlook on future prospects for MXene-based gas sensors, biosensors, and strain sensors, emphasizing their potential to revolutionize sensing technologies.