Two-Dimensional Transition Metal Dichalcogenides for Gas Sensing Applications

Abstract

The fast-growing earth population and the industrial growth of developing economies in Latin America and Asia have generated increasing air, water, and agricultural pollution in urban regions with consequences to human health. Most industrial sites are in urban regions, thus creating a challenge to ensure air quality and environment monitoring. Despite a growing diagnostic toolkit and a plethora of therapeutic interventions, a key challenge remains in the control of widespread diseases like cancer and diabetes. In the last decades, several semiconducting oxides have been used to detect dangerous or toxic gases. The excellent gas sensing performance of these gas sensor devices has been observed at high temperatures, which forbids their use for the detection of flammable and explosive gases. To overcome the problems such as selectivity, high sensitivity, and operation temperature, atomically thin transition metal dichalcogenides, which are two-dimensional (2D)-layered materials with large surface areas and tunable bandgaps, have emerged as a candidate for gas sensors. In the present book chapter, the recent advancement in the gas sensors, based on two-dimensional (2D) transition metal dichalcogenides, has been comprehensively discussed. In the first section, the recent advances on synthesis process and the properties of these materials have been discussed. The next section depicts the layered transition metal dichalcogenides (TMDs) and their recent advances for application in the field of gas sensors. The challenges and opportunities in gas sensing are discussed, with emphasis on the sensing mechanisms. The third and fourth sections highlight the functionalization of TMDs with noble metals and other metal oxides to investigate the gas sensing properties. Finally, as summary, the prospects of these two-dimensional transition metal dichalcogenides have been outlined for the development of highly efficient future generation gas sensors for accelerating the commercialization of the same.