空气主要组分在Ag表面的吸附行为研究

空气中熔融的Ag能够溶解自身体积的22倍氧气，冷却固化过程中其他气体(N₂、CO₂等)几乎为零。吸附是气体溶解的第一步，本文基于量子化学和簇模型的方法建立空气主要组分N₂、O₂、CO₂于Ag表面的吸附模型，研究Ag表面对空气主要组分的吸附行为。结果显示，O₂在Ag(100)、Ag(110)、Ag(111)上的吸附能都为最大，空气中Ag的周围主要吸附O₂，且几乎不产生与其他非氧组分的直接接触；Ag表面上N₂、O₂、CO₂的解离都需要一定的热激活条件，O₂在Ag表面的解离能垒低于N₂和CO₂，更容易解离成O吸附在表面。因此，Ag对空气中的O₂具有选择性吸附的功能。

Study on adsorption behavior of the main components of air on Ag surface

The molten Ag in air is capable of dissolving 22 times its own volume of oxygen, but the amounts of other gases (N2, CO2 etc.) released from silver during the cooling and curing process are almost zero. Adsorption is known to be the first step of gas dissolution, so the adsorption behavior of N2, O2 and CO2, the main components of air, on the Ag surface was investigated by the method based on quantum chemical theory and clusters model. The results show that the adsorption energy of O2 on Ag (100), Ag (110) and Ag (111) is the largest, so the surrounding area of Ag in air is mainly adsorbed with O2 and almost no direct contact with other non-oxygen components can be observed. The dissociation of N2, O2 and CO2 on the Ag surface requires certain thermal activation conditions, and the dissociation energy barrier of O2 on the Ag surface is lower than that of N2 and CO2., As a result, O2 is more readily dissociated into O atoms which are adsorbed on the surface. Therefore, Ag can selectively adsorb O2 in air.