MXenes: Emerging Materials for Environmental Biochemical Sensing Platforms

ABSTRACT Smart sensors for detecting biochemical substances are desired for various applications such as wearable electronics, diagnosis, and environmental monitoring. For the past decades, the rapid development of nanomaterials has enabled significant improvement of sensing devices based on the nanomaterials, due to their superior physical and chemical properties. However, sensing platforms with good sensitivity, selectivity, stability, and facile fabrication processes suitable for mass production are still a challenge. MXenes (e.g., transition metal carbides, nitrides, and carbonitrides), among those potential candidates for sensing materials, show promising potential with their intrinsically two‐dimensional large interactive area, wide‐range‐tunable material properties, active surface chemistry, and excellent processability for large‐scale fabrication. Here, we provide a critical review of the MXene‐based sensing technologies. The synthesis strategies and material properties are systematically summarized. The working mechanisms corresponding to the material structure for MXene‐based sensors are classified into subcategories and discussed respectively. The representative works are analyzed, and performance‐enhancing strategies are revisited and summarized. Finally, the challenges that hinder MXene‐based bio/chemical sensors from commercialization and the outlook on the further development of MXene sensing electronics are presented.