A DFT study of Mg9O9 nanoring for gas sensing and removal applications

Abstract

The toxic gas molecules are extremely harmful to both the environment and human health. To address this issue, we need to develop materials that can detect these gases and assist in their removal from the surrounding. Here, we analyzed the structure and electronic properties along with stability of newly predicted Mg9O9 nanoring i.e. allotrope of cyclo[18]carbon (C18 nanoring) employing density functional theory (DFT). In addition, present work also investigated the sensing properties of Mg9O9 nanoring towards toxic gases such as CO, NO and NH3. The substantial interaction of NO and NH3 gases with Mg9O9 nanoring is confirmed by the high adsorption energy and short adsorption distance. In contrast, weak interaction of CO gas molecule with Mg9O9 nanoring is verified by the comparatively long adsorption distance and small adsorption energy. The modulation in the dipole moment of the nanoring after adsorption of toxic gas molecules further confirms interaction between them. Our results indicate that the Mg9O9 nanoring is suitable for work-function-based sensor for NO and NH3 gases, as well as an electronic sensor only for NO gas molecule. The Mg9O9 nanoring shows an optimal recovery time (τ) for NO gas, indicating its applications as a sensor. Conversely, a longer τ observed for NH3 gas with Mg9O9 nanoring depicts its potential for gas adsorption or removal from the environment. Our findings unequivocally demonstrate that the Mg9O9 nanoring can function as a highly effective toxic gas sensor.