Transition metal dichalcogenide based toxic gas sensing

Having affordable, power-lean, yet highly sensitive and selective gas sensors is essential to enable the widespread and continuous monitoring of air pollutant and toxic gases. In the last years the research community has identified two-dimensional transition metal dichalcogenides as gas sensitive nanomaterials with high potential for developing a new generation of room-temperature operated devices for trace detection in the ambient. This paper reviews the developments and achievements of the last few years, identifies current shortcomings where breakthroughs are most needed, and discusses aspects where research efforts should be put to overcome the main difficulties experienced. These efforts range from gaining more insight in the gas sensing mechanisms to ameliorating the synthesis of transition metal dichalcogenide nanomaterials for better controlling surface, interface and edge chemistry and defects.