摘要
为了探究乙醇胺催化脱氢法中乙醇胺与催化剂之间的作用机理,依据密度泛函理论(DFT),研究了乙醇胺在Ni(111)和Cu(111)表面上各高对称位的吸附机制,优化了乙醇胺在吸附位点Top、Bridge、Hcp和Fcc的吸附结构,并对最稳定吸附构型的吸附能、电荷转移和态密度进行了对比分析。结果表明:乙醇胺以氨基上的氮原子接近Ni(111)和Cu(111)表面Top位时的吸附能最小,分别为-1.31 eV和-1.04 eV,此时乙醇胺向金属表面的电荷转移量分别为0.08e和0.06e(e为1个电子的电荷量),且吸附后分子内部键长基本不变,说明乙醇胺在Ni(111)和Cu(111)表面的吸附均属于物理吸附,电子态密度分析的结果与当前结果一致;乙醇胺与金属Ni之间的相互作用更强。这些结果为深入了解乙醇胺在Ni(111)和Cu(111)表面的反应机理提供了理论基础。
To explore the mechanism of the interaction between ethanolamine and catalyst in the catalytic dehydrogenation of ethanolamine,the adsorption of ethanolamine on Ni(111)and Cu(111)surfaces with high symmetry sites is investigated by using density functional theory(DFT).The adsorption structure of ethanolamine is optimized at the Top,Bridge,Hcp and Fcc sites,and the adsorption energy,charge transfer and state density of the most stable adsorption configuration are analyzed comparatively.The results show that the adsorption energy of ethanolamine gets the smallest as the nitrogen atom of the amino group approaching the surface Top site of Ni(111)and Cu(111),and is determined as-1.31 eV and-1.04 eV respectively.At this point,the charge transfer amount of ethanolamine to the metal surface is determined as 0.08e and 0.06e respectively.The internal bond length of ethanolamine is basically unchanged after adsorption,which indicates that the adsorption of ethanolamine on the surface of Ni(111)and Cu(111)belongs to physical adsorption.The results of electron state density analysis coincide with the above mentioned ones,which verifies the stronger interaction between ethanolamine and Ni.
作者
张辰
丁万成
张景峰
余云松
张早校
ZHANG Chen;DING Wancheng;ZHANG Jingfeng;YU Yunsong;ZHANG Zaoxiao(School of Chemical Engineering and Technology, Xi’an Jiaotong University, Xi’an 710049, China)
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2020年第6期168-175,共8页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(51506165,21736008)。
