Density Functional Studies Of Hydrogen Sulfide Molecule Adsorption On Intrinsic Graphene And Al-doped Graphene

Graphene is a kind of zero band gap,the crystal structures of two-dimensional honeycomb carbon six ring,can also be considered a single atom thick graphite.Graphene attracted a widespread attention of the world due to its various aspects of the unique nature,however graphene is still an experimental material.At present,the production of graphene is still very low,and the production cost is high,the quality is not stable,etc.,these factors all restrict the practical application of graphene further.However,this does not affect the charm of the graphene,because graphene has great application potential in gas sensors,electronic optical device,battery and super capacitor.The reason that graphene can be used in gas sensor field is the electron mobility and extremely sensitive to the change of carrier concentration.Because the limited sensitivity to detect gas,graphene has a higher sensitivity only for a few gas?e.g.,NO2,NO,etc.?.So,in order to improve the gas adsorption ability of graphene,researchers started from defective graphene and doped graphene to study the adsorption of gas molecules.Various defects in graphene have been introduced in the article,and expounds the causes of defects in detail.For the characterization of graphene defects,this paper also introduced several kinds of detection means.Finally,the paper based on density functional theory?DFT?method of first principles,has studied the adsorption of H₂ S molecular in the surface of intrinsic graphene and Al-doped graphene by calculating the geometric structure,net charge transfer,orbit parameters etc.of adsorption configurations after structure optimization.Therefore,we get the following conclusion:?1?H₂S molecular only exists the weak physical adsorption with intrinsic graphene,however,due to the presence of ionic bond and covalent bond,there has been a strong interaction of chemical adsorption between the H₂ S molecular and Al doping graphene.?2?the adsorption energy of H₂ S molecular on Al doped graphene is 30 times higher than that on intrinsic graphene,and the net charge transfer between them is more than the latter.?3?Graphene can be found the conductivity has improved after Al atoms doping,which be proved by HOMO and LUMO.