CS2和COS在y-A12O3表面吸附的密度泛函理论研究

煤气中的有机含硫化合物CS2和COS对环境及后续的反应带来很大的危害，常用Al2O3进行脱硫处理。小分子在固体表面的吸附是研究气固反应的基础。采用量子化学密度泛函理论方法研究了CS2和COS在y-Al2O3（110）表面的吸附，结果表明CS2最稳定的构型为C82的3个原子分别与表面的Al0一Al键中的3个原子作用，形成了（COS2）。一物种，此构型的吸附能为107．98kJ／mol；COS以SC键-9表面的1个Al-O键作用时最稳定，吸附能为99．99kJ／mol。通过分波态密度和小分子吸附前后净电荷的变化可知，在这两个构型中，小分子与表面有很强的相互作用。

Density functional theory study on the adsorption of CS2 and COS on the y-A1203 surface

CS2and COS are organic sulfur-containing compounds that often appear in coal gas. Trace of CS2 and COS not only harms the environment, but also brings economic problems within the down stream processes. A12O3 is a widely used desulfuri- zer. Molecular adsorption on surfaces is a fundamental step for the chemical reaction between gaseous and solid states. In this pa- per, CS2 and COS adsorption on the y-A12 03 （110） surface has been studied based on the density functional theory. It can be con- cluded that the most stable adsorption configuration for CS2 is three atoms in CSz interacting with the three atoms of A1--O--A1 bond, respectively, and a （COS2）2 species is formed. The adsorption energy is 107. 98 kJ/mol; the most stable adsorption structure for COS is that the S--C bond in COS interacting with the A1--O bond in A12 03 with an adsorption energy of 99.99 kJ/ mol. The partial density of state and Mulliken net charge show that there is a strong interaction between small molecules and the ）＇-A12 03 （110） surface.