Computational Studies on the Nitrogen-Doped Graphene Quantum Dots as Potential Sensor for Hazardous Gases

Graphene quantum dot-based sensors have demonstrated significant promise in the detection of dangerous air pollutants that harm the environment and endanger human health. The efficient trapping and separation of numerous hazardous gases from the environment have recently garnered substantial experimental and computational attention. Nitrogen doping significantly tunes the properties of graphene quantum dots and expands their potential applications. In this study, we have investigated the sensing mechanism of pristine graphene quantum dots (GQD) along with pyridinic nitrogen-doped defective graphene systems, i.e., GQD-DV/N4, for various hazardous gases, such as arsine (AsH 3 ), hydrogen sulfide (H 2 S), formaldehyde (HCHO), hydrogen cyanide (HCN), and phosphine (PH 3 ). Our study suggests that nitrogen doping in GQDs can significantly increase the adsorption strength for these hazardous gases. Our in-depth analysis proposes that adsorption is governed by the presence of hydrogen bonds between the hydrogen in the adsorbates and the nitrogen in the adsorbents. These findings should persuade scientists to rationally and methodically modify surfaces to serve as sensors for the detection of hazardous gases.