The Impact Of CO And O₂ Adsorption On Pt（001） With Ferroelectric Material

Nowadays, in the fuel cell that used noble metals platinum as proton exchange membrane. CO can be adsorbed easily on platinum surface which reduces the effective adsorption sites of H2 and causing the effect called "CO poisoning". Researchs have shown that: the properties of the supported metal can be improved by the ferroelectric film and different polarization directions can have a significant effect on the reaction rate,and ferroelectric materials have the abilities to control the catalytic reaction rate. Based on this, we have investigated the impact of the ferroelectric material about the adsorption of CO and O2.1. The CO adsorption on Pt film tuned by ferroelectric polarization: all the adsorption energy of the CO in all adsorption sites on Pt/(Ba TiO3)5/Pt and Pt/(Pb TiO3)5/Pt and Pt(001) surface were calculated by first-principles density functional theory, and the terminal mode of CO adsorption applied line type. The results have shown that: polarization can enhance the adsorption properties of CO on Pt with an enhancive adsorption energy about 0.8 e V compared to pure Pt(001), and the regular pattern was more applicable with the BaO/Pt and PbO/Pt. The polarization directions can lead to relatively large differences in adsorption in which TiO /Pt side is small but BaO/Pt and PbO/Pt side relatively large, which illustrates the effect of polarization to CO adsorption is a regulatory role. It is a good basis for the research of the surface adsorption of CO.2. The O2 adsorption on Pt film tuned by ferroelectric polarization: the adsorption of O2 were used by end and side style, which O2 were adsorbed on the surface of the Ba TiO3 and Pb TiO3 with platinum loaded. The results showed that: the adsorption of O2 on the platinum surface can be obviously enhanced whether using the Ba TiO3 or Pb TiO3. The regulatory influence of polarization to the O2 adsorption were weak when the O2 adsorption were taken place at the end of the Pt surface regardless the substrate. In this article, the O2 in this environment can be self-cleavage. These studies were meaningful for the research of the surface adsorption of O2.