Recent development in carbon dot-based gas sensors

Abstract

Carbon dots (CDs) are novel 0D nanomaterials discovered in the beginning of the 21st century. They have versatile properties due to which they have gained attention from researchers to successfully develop a wide variety of devices. Among them, one of the foremost is developing sensors capable of real-time detection of ultra-low concentration of gas molecules using CDs as an active sensor material. Gas sensors have both industrial and medical significance. Hence, in recent years more and more work has been carried out for developing gas sensors with good reproducibility and stability and high selectivity, sensitivity, response rate and recovery rate. Although several metal oxides and mesoporous materials have been developed to play the role of sensitive film, these materials have been found to be lacking in certain aspects. Addition of a uniformly dispersed CD film over metal oxide nanostructures, conducting polymers or mesoporous materials has enabled us to overcome their limitations. Here, we attempt to summarize the imperative role of CDs as an active material in gas sensors as we briefly discuss some of the synthesis routes. A detailed account on the optical and electrical properties of CDs and the recent developments in CD-based gas sensors is provided here.