A Theoretical Study Of The Adsorption Properties Of Small Gas Molecules On Functionalized BN Nanosheets

Graphene is a new carbon-based material and made successfully in the laboratory byNovoselov and Geim in2004. Then, graphene opened a new field of fundamental physics,and it has a broad application prospect in many areas of nanotechnology. In recent years,scientists pay great attentions on the two-dimensional structure is similar to the graphenesheet material, such as nitride, Sulfides, Oxides and other two-dimensional materials. This ismainly due to the special optical, electrical, magnetic properties of low-dimensional materialswith the hexagonal boron nitride (h-BN). The h-BN, with a stable chemical properties,antioxidant abilities, mechanical properties, and thermal properties of higher performance, hasa hexagonal arrangement and an important role in the field of hydrogen storage materials,catalyst supports, and environmental protection. But h-BN has not been widely used in theseareas. Therefore, study on the microscopic structure and adsorption properties of h-BNgeometry is very important.As a new material, we can change the structure and electronic properties of single h-BNby modification or dopant other atoms, which has become an urgent problem to expand itsapplications. In this thesis, we hava investigated the lamellar h-BN with dopant or modified tofunctionalized and then study the function of h-BN material in terms of the application of thecatalyst carrier. The main contents are as follows:1．We study the structure of CO and O2adsorbed on pristine and Pt soft landing on boronnitride nanosheets, respectively. The results show: when O2and CO adsorbed on pristineh-BN, electronic structure of gas molecules isn’t significantly change. It shows that theadsorption of CO and O2on pristine is the weak physical adsorption. When gas moleculesadsorbed on Pt/h-BN, the bond length and charge transfer of gas molecules are increasing,and the electronic structure changes significantly, it enhanced the interaction between the gasmolecules and Pt/h-BN.2．We investigate the structure and electronic properties of O2and CO adsorbed on Pt(Pt2) on functionalized boron nitride nanosheets. Then we analyse the bond length, adsorptionenergy, charge transfer of system, and find the interaction between the gas molecules and Pt(Pt2) on functionalized boron nitride nanosheets is enhanced. Because of the hybridizationbetween2p orbital of C and O and the5d orbital of Pt, impurity states appeared in the vicinityof the Fermi level. In addition, chemical stability weakened when they are adsorbed on Pt2onfunctionalized boron nitride nanosheets.