摘要
采用密度泛函理论(DFT)研究了C_(3)H_(8)和CO_(2)在Ni_(x)Cu_(y)-B_(24)N_(28)(x+y=4,x=1、2、3、4)表面吸附及速控步骤反应机理.计算了C_(3)H_(8)、CO_(2)和相应中间体在Ni_(x)Cu_(y)-B_(24)N_(28)表面的吸附能以及6条可能路径下的反应热和活化能.计算结果表明,C_(3)H_(8)和CO_(2)在Ni_(x)Cu_(y)-B_(24)N_(28)表面是物理吸附,C_(3)H_(8)+CO_(2)→CH_(3)CHCH_(3)+OCOH是最有利的路径,其在不同催化剂表面的活化能顺序是NiCu_(3)-B_(24)N_(28)(1.42 eV)、Ni_(2)Cu_(2)-B_(24)N_(28)(1.57 eV)、Ni_(3)Cu-B_(24)N_(28)(1.62 eV)、Ni_(4)-B_(24)N_(28)(1.75 eV).由此可知,在Ni_(x)Cu_(y)-B_(24)N_(28)催化CO_(2)氧化C_(3)H_(8)的体系中,Cu含量直接影响其催化活性,即NiCu_(3)-B_(24)N_(28)用于催化CO_(2)氧化C_(3)H_(8)有一定优势.
Density functional theory(DFT)was used to study the adsorption and the mechanism of the rate-controlling step of C_(3)H_(8)and CO_(2)on the surface of Ni_(x)Cu_(y)-B_(24)N_(28)(x+y=4,x=1,2,3,4).We calculated the adsorption energy of C_(3)H_(8),CO_(2)and other corresponding intermediates on the surface of Ni_(x)Cu_(y)-B_(24)N_(28),and calculated the relevant reaction heat and activation energy under the six possible paths.The calculation results showed that C_(3)H_(8)and CO_(2)are physically adsorbed on the surface of Ni_(x)Cu_(y)-B_(24)N_(28),C_(3)H_(8)+CO_(2)→CH_(3)CHCH_(3)+OCOH was the most favorable path,and its activation energy sequence on the different catalyst surfaces was NiCu_(3)-B_(24)N_(28)(1.42 eV),Ni_(2)Cu_(2)-B_(24)N_(28)(1.57 eV),Ni_(3)Cu-B_(24)N_(28)(1.62 eV),Ni_(4)-B_(24)N_(28)(1.75 eV).It is concluded that the Ni_(x)Cu_(y)-B_(24)N_(28)catalytic system used for the oxidation reaction of C_(3)H_(8)by CO_(2),the content of Cu directly affects its catalytic activity,that is,NiCu_(3)-B_(24)N_(28)is more advantageous for catalyzing the oxidation of C_(3)H_(8)by CO_(2).
作者
律佳媛
任瑞鹏
吕永康
LU Jia-yuan;REN Rui-peng;LU Yong-kang(State Key Laboratory for Clean and Efficient Utilization of Coal Energy Jointly Established by The Ministry of Science and Technology and Shanxi Province,Taiyuan University of Technology,Taiyuan 030024,China;Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering,Taiyuan 030024,China)
出处
《分子催化》
CAS
CSCD
北大核心
2022年第2期137-144,共8页
Journal of Molecular Catalysis(China)
基金
国家自然科学基金资助项目(22078226)
山西浙大新材料与化工研究院项目(2021SX-AT004和2021SX-FR001)
