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论文类型：期刊论文

发表时间：2016-09-01

发表刊物：13th International Conference on Carbon Dioxide Utilization (ICCDU)

收录刊物：SCIE、EI、CPCI-S、Scopus

卷号：15

期号：,SI

页面范围：107-114

ISSN号：2212-9820

关键字：Carbon dioxide; Hydrogen; Adsorption; Fe; Density functional theory

摘要：Periodic density functional theory calculations were performed to investigate the adsorption and activation of CO2 and H-2 over Fe(10 0) surface. Four stable adsorption configurations of CO2 were identified and the energetically most stable adsorption was found to occur on the 4-fold hollow site where the C atom of CO2 sits right above the second layer Fe atom and the two O atoms bound at the center of two Fe-Fe bridge bonds on the surface. H-2 molecule dissociates to H* atoms upon adsorption. Only when H-2 adsorbs on the top sites of the metal surface it can be stabilized in an associative or molecular form. Small energy barriers were found for H-2 dissociation on Fe(10 0) which indicates that H-2 dissociates very fast on the catalyst surface. CO2 adsorption stability could be influenced by the surface coverage of H*. We observed a significant decrease of CO2 adsorption strength when surface H* coverage becomes higher than 2/3 ML. (C) 2016 Elsevier Ltd. All rights reserved.