A review on environmental gas sensors: Materials and technologies

The rapidly increasing population, industrial emissions, vehicle exhaust and open burning of garbage waste are the main cause of pollutants which regularly deteriorate the natural environmental conditions. The continuous monitoring of these pollutants is necessary to prevent environmental deterioration. Various types of instruments are available to monitor the pollutes and harmful gases, which are time consuming, expensive and rarely used for in real-time areas. In recent years, scientific community has carried out extensive research on ideal environmental sensor from theory to practice. There are different types of materials such as carbon nanotubes (CNTs), Graphene (G), metal/metal oxide nanoparticles, two dimensional (2D) nanomaterials and hybrid nanostructures, which have been widely investigated as sensing materials for environmental gas sensors. So keeping aforesaid in mind, this review article focuses on the emerging materials and technologies that can identify for environmental monitoring applications.