Catalytic hydrolysis of COS over CeO2 (110) surface: A density functional theory study
Catalytic hydrolysis of COS over CeO2 (110) surface: A density functional theory study
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CeO2（110）表面上 COS 的催化水解：密度泛函理论研究
DOI：
10.1016/j.apsusc.2017.04.119
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发表时间：
2017
影响因子：
6.7
通讯作者：
Sun Xin
中科院分区：
文献类型：
--
作者：
Song Xin;Ning Ping;Wang Chi;Li Kai;Tang Lihong;Sun Xin
采用dmol3模型，通过密度泛函理论（DFT）研究了COS在CeO2（110）表面催化水解的反应途径。对建议的COS水解为co2和H2S的途径进行了热力学稳定性分析。h2o - ceo2的吸附能绝对值大于COS-CeO2的吸附能绝对值。同时，吸附能和几何形状表明H2O比COS更容易吸附在CeO2（110）表面。H2O在节理吸附过程中起桥梁作用。H2O在CeO2（110）表面形成更多的单键和单键h基团。ceo2使最大能垒降低76.15 kcal/mol。氢从H2O向COS的迁移是水解反应的关键。单键通道比单键通道更容易发生。实验结果表明，添加ceo2可提高COS去除率，将100% COS去除率从180 min延长至210 min。fe2o3和ceo2水解COS的差异表现在原子电荷转移和形成h单键do键和Hsingle bondS键。H2O中的H到COS中S在ceo2上的转移作用降低了水解反应的能垒，提高了COS水解反应的活性。
Density functional theory (DFT) calculations were performed to investigate the reaction pathways for catalytic hydrolysis of COS over CeO2(110) surface using Dmol3model. The thermodynamic stability analysis for the suggested routes of COS hydrolysis to CO2and H2S was evaluated. The absolute values of adsorption energy of H2O-CeO2are higher than that of COS-CeO2. Meanwhile, the adsorption energy and geometries show that H2O is easier adsorbed on the surface of CeO2(110) than COS. H2O plays a role as a bridge in the process of joint adsorption. H2O forms more Cesingle bondOsingle bondH groups on the CeO2(110) surface. CeO2decreases the maximum energy barrier by 76.15 kcal/mol. The migration of H from H2O to COS is the key for the hydrolysis reaction. Csingle bondO channel is easier to occur than Csingle bondS channel. Experimental result shows that adding of CeO2can increase COS removal rate and prolong the 100% COS removal rate from 180 min to 210 min. The difference between Fe2O3and CeO2for the hydrolysis of COS is characterized in the atomic charge transfer and the formation of Hsingle bondO bond and Hsingle bondS bond. The transfer effect of H in H2O to S in COS over CeO2decreases the energy barriers of hydrolysis reaction, and enhances the reaction activity of COS hydrolysis.