Functionalized graphene-based Quantum Dots: Promising adsorbents for CO, NO2, SO2, and NH3 Pollutant Gases

The development of more sensitive and accurate sensors is essential to monitor the levels of pollutant gases that are causing high damage to the biosphere. One of the most promising materials for such application is graphene, which, due to its extensive collection of properties, has shown itself capable of adsorbing gas molecules. Thus, the present work aims to investigate the adsorption of carbon monoxide (CO), nitrogen dioxide (NO2), sulfur dioxide (SO2), and ammonia (NH3) on Graphene Quantum Dots (GQD) through electronic structure and molecular dynamics calculations. The data suggest doping GQDs with boron, nitrogen, or aluminum can greatly improve their adsorbing capabilities. For both CO and NH3, a functionalization with aluminum is the most effective, while the adsorption of SO2 was not much affected by any of the doping designs. Notably, quantum dots doped with all three heteroatoms are extremely promising with respect to the application in NO2 gas sensors. Thereby, the results indicate that accurate and resilient gas sensors based on doped GQDs may be a good substitute for the current sensors in the market.