CO Adsorption Performance Of Ni/Pt-modified Single-walled Aluminum Nitride Nanotubes

Carbon monoxide(CO)is one of the main gases that cause air pollution,and it is also a harmful gas that endangers human life and health.Therefore,the filtration and detection of CO has very important research significance and broad application prospects.Aluminum nitride nanotube(Al NNT)have potential applications in CO filtration and detection due to their large specific surface area,tunable band gap,and high thermal and chemical stability.However,the adsorption strength of CO molecules on the surface of Al NNT is weak.The surface modification with metal atoms can effectively improve the interaction between Al NNT and CO molecules and improve the sensitivity of Al NNT to CO molecules.In this paper,the transition metal atoms Ni-and Pt-modified(5,5)single-walled Al NNT(denoted as Ni-Al NNT and Pt-Al NNT,respectively)were selected as the research objects.The interactions between Ni-Al NNT and Pt-Al NNT and CO were studied by first-principles calculation based on density functional theory.The main contents and conclusions are as follows:(1)The geometric structure,electronic properties and interaction with CO molecules of Ni-modified Al NNT were studied.The results show that the energy of Ni atom adsorbed on the top site of N atom in Al NNT surface is the lowest.Three CO molecules can be adsorbed near a Ni atom,and the average adsorption energy is between 1.529-2.188 e V.The modification of Ni atom effectively improves the adsorption capacity of Al NNT for CO molecules.(2)The electronic properties and CO adsorption properties of Pt-modified Al NNT were studied.The results show that four complete CO molecules can be adsorbed around a Pt atom.In the case of multiple Pt atoms modification,the adsorption mass fraction of CO molecules can reach 26.05%.The modification of Pt atoms improves the adsorption capacity of Al NNT for CO molecules,which is due to the strong hybridization between the d orbital of Pt atom and the s and p orbital of C atom.The molecular dynamics simulation based on the first-principles shows that the thermal stability of Pt-modified Al NNT adsorbing CO molecules is very good.In summary,the modification of transition metal Ni and Pt atoms improves the ability of Al NNT to adsorb CO molecules,which makes the material promising as an excellent candidate material for filtration or detection of toxic CO molecules.