基于密度泛函理论对Hg在纯CeO2表面的吸附机理进行了理论计算，采用p（3×3）的二维超晶胞模型计算了CeO2 3个不同表面上不同位点对汞的吸附能，计算结果表明，Hg在纯CeO2表面吸附能力较弱，为物理吸附，Hg原子与CeO2未形成有效化学键。为了进一步研究Hg在CeO2表面的吸附机理，计算了Hg在Pd掺杂的CeO2（Pd-CeO2）表面的吸附机理，结果表明，Hg在Pd-CeO2表面吸附能较强，为化学吸附，Hg原子与Pd-CeO2之间形成有效的化学键，说明Pd的掺杂有利于提高CeO2对汞的吸附能力。为了量化纯CeO2和Pd-CeO2的汞脱除效率，对Hg在纯CeO2和Pd-CeO2表面的脱除进行了实验研究。实验结果表明，纯CeO2对汞的脱除效率较低，贵金属Pd的掺杂能够有效提高CeO2的汞脱除效率，与理论计算的结果相符。
The adsorption mechanism of Hg on pure CeO2 surface was studied by the density functional theory. The adsorption energy of Hg on different surfaces and different sites of CeO2 was calculated by two-dimensional supercell model of p(3×3). The results show that the adsorption capacity of Hg on pure CeO2 is weak, which is a physical adsorption, and the Hg atom and CeO2 do not form effective chemical bonds. In order to further study the adsorption mechanism of Hg on CeO2 related surface, the adsorption mechanism of Hg on Pd doped CeO2(Pd-CeO2) surface was also studied. The results show that the adsorption capacity of Hg on Pd-CeO2 is strong, which is a chemical adsorption, and the Hg atom and Pd-CeO2 form effective chemical bonds. The adsorption capacity of Hg on CeO2 surface is enhanced due to the doping of Pd. In order to further quantify the adsorption efficiency of Hg on the surface of pure CeO2 and Pd-CeO2, the experimental study has been carried on. The experimental results show that the adsorption efficiency of Hg on pure CeO2 is low, and doping of Pd can effectively improve the adsorption efficiency of CeO2, which are consistent with the results of theoretical calculation.
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