Study On The Electron Transport And Gas Detection Mechanism Of Boron/Silicon Based Composite

In recent years, the two-dimensional graphene-like materials have been rapidly infiltrated into various fields of research, attracting the attention of scientists in the world. Boron and silicon are two elements that are adjacent to carbon, but researches on properties of the composite based on boron/silicon are relatively few. By using the first principles combined with non-equilibrium Green’s function method, transport properties of devices based on boron/silicon are calculated and discussed. The main research is divided into the following parts:Firstly, boron-silicon monolayer structures have been studied. Based on different concentrations of two dimensional boron-silicon compounds: B₅Si, B₂Si, BSi, BSi₂, BSi₃, and BSi₄, the electronic transport properties of the compounds are discussed compared with silicene and substance composed by boron. The negative differential resistance phenomenon of boron-silicon sheets can be widely used in industry.Secondly, the gas-sensitive properties of two-dimensional BSi structures doped Ti/Cu elements have been structured. BSi sheet on zigzag direction is choosed as the based material for gas sensor. Doped by Ti and Cu, the selectivity of gas adsorption is discussed after the adsorption of gas molecules（N₂, H₂, H₂O, CO, CO₂）. It is found that BSi sheet can be as the material of gas sensor for H2.Thirdly, the gas-sensitive property of B₃₅ cluster doped Li elements has been structured. B₃₅ doped Li atom is choosed as the based material of gas sensor. The selectivity of gas adsorption among 5 different gases（H₂, N₂, CO, CO₂, NH₃） is explored. In addition, the hydrogen storage capacity is discussed.