A novel approach for detection of NO2 and SO2 gas molecules using graphane nanosheet and nanotubes - A density functional application

Using ab initio technique, electronic properties including structural stability of the chair-like graphane nanosheet (HGr-NS) and nanotube (HGr-NT) is explored. The structural stability of graphane nanosheet/nanotube is confirmed with the influence of formation energy and phonon band structure. The density-of-states spectrum provides the insights on charge transfer upon these small molecules adsorbed on graphane material. The energy band gap of graphane base material get differs when toxic gas molecules (NO2 and SO2) interacted with HGr-NS and HGr-NT. The adsorption energy upon interaction of NO2 and SO2 molecules on graphane material is found to be in the range of - 0.5 and - 0.3 eV, respectively. Further, the average energy gap variation of graphane system is noticed to be in the range of 34.67 to 55.95% for NO2 adsorbed graphane and 87.3 to 151.45% for SO2 adsorption on graphane sheets. Notably, a shorter recovery time is obtained on graphane sensor upon desorption of SO2 molecules. Besides, the interaction of SO2 small molecule on hydrogenated graphene nanosheet and nanotube is found to be more favorable rather than NO2 molecules. The findings propose the application of HGr-NS and HGr-NT for the detection of NO2 and SO2 small molecules.