Adsorption Properties Of Iron And Bilayer Phosphorene Surface: A First Principle Study

Surface adsorption is an important scientific research issue in the fields of surface catalysis,tribology,hydrogen storage,electrochemistry,and sensor.Iron?Fe?has a wide range of applications,such as in the fields of electrochemistry,corrosion and catalysis.Anti-corrosion of Fe surface is a major research topic.Small molecules adsorption on surface is an important issue for the corrosion of Fe surface.Therefore,it is crucial to study the adsorption behavior of molecular gases on Fe surface.In addition,the two-dimensional material black phosphorus,because of its direct band gap,has a certain limit in conductive properties of the practical application.Atomic adsorption can improve the performance of phosphorene materials,and then expand the application of phosphorene materials in various fields.Therefore,surface atomic adsorption is an important modulation method to improve the properties of engineering materials.This paper was based on density functional theory?DFT?method;the specific research was as follows:Adsorption properties of different molecules?O₂,H₂ O,CO₂,H₂,N₂,CO,He?on Fe?111?and carbon-containing Fe?111?surface were investigated by DFT.The results show that the adsorption energy of different molecules on Fe?111?is in the order of O₂ > CO > N₂ > H₂ > CO₂ > H₂O > He,and Fe?111?is highly reactive to almost considered molecules except He.Compared to Fe?111?,carbon enhances the ability of H₂ adsorbed on Fe?111?,and reduces the ability of Fe?111?to adsorb other molecules.Gases such as CO₂ and N₂ with full shell electronic structures,can also be strongly adsorbed on Fe?111?,indicating that ?-Fe can be an efficient catalyst for catalyzing CO₂ and N₂ related reactions.However,in terms of preservation of ?-Fe,we have to exclude not only active gases such as O₂ and H₂O,but also the commonly used protective gases such as CO₂ and N₂.The geometric/electronic structures of bilayer phosphorene and the adsorption of rare gas?Xe,Kr,Ar?on its interlayer were studied with DFT.The results show that the adsorption of rare gases leads to deformation of the structure of bilayer phosphorene and modifies its electronic structure.When 6 Xe,Kr or Ar atoms are adsorbed in the interlayer area of bilayer phosphorene,the corresponding system changes from direct to indirect band gap,and the effective mass of electron at the bottom of the conduction band is in the order of me?Xe?> me?Ar?> me?Kr?,thus the electron carrier mobility is in the order of ??Xe?< ??Ar?< ??Kr?.Atomic adsorption changes the conductivity of the bilayer phosphorene,which can help researchers to understand the geometry dependence of the electron conductivity of bilayer phosphorene.