Adsorption and sensing performances of transition metal doped ZnO monolayer for CO and NO: A DFT study

In this study, theoretically, density functional theory was employed to explore the adsorption behavior of CO and NO prevalent hazardouss gases, on transition metal (TM = Fe, Co, Ni, and Cu) doped ZnO monolayer. The multifaceted analysis encompasses an array of critical aspects, including the adsorption structure, adsorption energy, density of states (DOS) and electron transfer to unravel the adsorption behavior. Our calculations show that TM atom doped ZnO monolayer exhibit high stability. TM doped can significantly enhance the interaction between the gas molecules (CO and NO) and the ZnO monolayer. Analysis of the recovery time and electrical conductivity of the adsorbed systems suggests that the Co-ZnO could be a suitable material for CO sensing,while the Cu-ZnO and Ni-ZnO can be used for NO sensing. These results suggest that transition metal doped can be a promising sensor candidate for toxic gas molecules adsorption and detection.