Gas sensing with heterostructures based on two-dimensional nanostructured materials: A review

Gas sensors are being used in diverse applications in security, food safety, environmental monitoring, indoor air quality monitoring, personal healthcare, etc. During the past decade, two-dimensional (2D) nanostructured materials have attracted intense attention because of their unique chemical and physical properties. They have demonstrated promising potential for gas sensing devices because of their large surface-to-volume ratio, high surface sensitivity, and excellent semiconducting properties. Combining 2D nanostructured materials with other dimensional materials also holds great promise for developing high-performance gas sensors. This review presents a comprehensive summary of recent progress in gas sensors with advanced heterostructures based on 2D nanostructured materials. Furthermore, the fundamental sensing mechanisms of different types of gas sensors are systematically discussed, and key device architectures and their performances are summarized. Finally, the challenges and prospects for the future development of each type of gas sensor are addressed to promote better sensing-device architectures.