Pt基电极材料硫中毒机理的计算机模拟研究

采用基于密度泛函理论的第一性原理方法和超原胞模型，计算并分析了Pt及Cu掺杂的Pt基合金的表面态密度，以及S在Pt及Pt基合金表面的吸附能和态密度情况.考虑了多种掺杂体系及吸附构型，结果表明：Cu掺杂会降低Pt基体系表面费米能级附近态密度，Pt皮肤的存在可以有效地减小Cu掺杂对体系表面态密度的影响；与S在纯Pt表面吸附相比较，S在掺杂体系表面的吸附能较小，且S的吸附对掺杂体系费米能级附近表面态密度影响较小. 以上研究结果有助于为改善Pt基电极材料的催化性能，尤其是其抗S中毒性能提供理论依据.

A first principles study on the mechanism of sulfur poisoning for Pt-based electrode materials

The electronic and energetic properties of the pristine and S adsorbed Pt and Cu-doping Pt surfaces are presented by first principles method. It is found that: the peak of the density of states near to the Fermi level would be lowered by the Cu dopant, while the Pt-skin would reduce the influence of the Cu dopant on the density of states. Comparing with the undoped system, the Cu dopant will reduce the interaction between the S and Pt surface and the peak of the density of states near to the Fermi level is much less influenced by the S adsorption. The results can theoretically help to improve the catalytic properties and explain the mechanism of sulfur poisoning for Pt-based electrode materials.