Study On Cu/Zr/Ti-doping Graphenes And Their Adsorption Properties Of N/S Oxides

The intrinsic graphene?IG?exhibits excellent comprehensive properties because of its unique and stable two-dimensional planar structure.However,there are still many problems to be solved for its functionalization and applications.And the doping of other elements is one of the effective ways to ameliorate the properties of IG.And SO₂ and NO gases are typical areoplane contaminants in the atmosphere,and we are always looking forward to removing such pollutants.In this paper,the structures and properties of Cu-,Zr-and Ti-doping graphene?ie.Cu-IG,Zr-IG and Ti-IG?systems are investigated by using the first-principles method based on density functional theory and Materials Studio software.And then the adsorption properties of SO₂/NO molecule on Cu-IG,Zr-IG and Ti-IG systems were explored from the aspects of geometric structure,energy properties and electronic properties.The results show that the symmetry breaking and structural distortion occur in the Cu-IG,Zr-IG and Ti-IG systems.The larger the covalent radius of impurity atom is,the more obvious the structural distortion is.The Cu-IG system exhibits narrow band gap semiconductor properties,and the Zr-IG and Ti-IG systems exhibit p-type semiconductor characteristics.The intrinsic factor of the change of structures and properties of Cu-IG,Zr-IG and Ti-IG systems is the redistribution of electronic states.The photoconductivity characteristics of Cu-IG,Zr-IG and Ti-IG systems have also changed,which indicate that these systems can be used as visible light sensitive materials and materials of sensors.The adsorption of SO₂ and NO molecules on IG belong to physical adsorption.And it may be used as adsorption material for SO₂ and NO gases.The electronic conductivity and magnetism of the IG-SO₂ and IG-NO systems show that IG is not suitable as sensitive materials for detecting SO₂ and NO gases.The Cu-IG,Zr-IG and Ti-IG systems have strong adsorption effects on SO₂ molecule,which belong to chemical adsorption.And the adsorption strengths of SO₂ molecule on Cu-IG,Zr-IG and Ti-IG systems increase in turn,which make them can be used as adsorption materials for SO₂ gas.They can also be used as sensitive materials to detect SO₂ gas,for the significant changes in magnetism and conductivity of SO₂-Cu-IG system,and the obvious changes in conductivity of SO₂-Zr-IG and SO₂-Ti-IG systems.For NO molecule,the Cu-IG,Zr-IG and Ti-IG systems also have strong adsorption effects,which also belong to chemical adsorption.And the adsorption strength of NO molecule on Cu-IG,Ti-IG and Zr-IG systems decrease in turn.Thus,they can be applied to adsorb NO gas.They can also be used as detecting materials for NO gas.Among them,the Cu-IG system is more suitable for the detection of NO gas by monitoring the changes of conductivity and magnetism.