Gas sensors based on two-dimensional materials and its mechanisms

Inspired by the interesting properties of two-dimensional (2D) layered graphene, much attention has been focused on finding new 2D materials. After the advent of graphene, 2D layered materials such as transition metal dichalcogenides, layered metal oxides, phosphorene, and hexagonal boron nitride have been fabricated. 2D layered materials have unique physical and chemical properties which can be used in catalysis, electronics, energy storage, optoelectronics, and chemical sensors. As they are large specific surface areas with active sites, 2D materials are favorable for gas sensor applications. This chapter provides information on the basics of gas sensors, sensor configuration for 2D materials, available 2D materials for gas sensing, and influential parameters. A part of the chapter sheds light on the mechanism of gas sensing in 2D materials. Finally, open challenges and future prospects for engineering 2D nanostructures for high-performance gas sensors are presented.