低碳化学与化工2024，Vol.49Issue(11)：28-35,8.DOI:10.12434/j.issn.2097-2547.20240067
OH*对Ni(111)上甲烷部分氧化成CO影响的理论计算
Theoretical calculation of effect of OH*on methane partial oxidation to CO on Ni(111)
摘要
Abstract
In order to promote the transformation of China's energy structure and alleviate the pressure of energy shortage,it is of great practical significance to partially oxidize natural gas(methane)with abundant reserves into syngas.The catalysts commonly used in this process is the Ni-based catalysts,which are prone to carbon deposition and inactivation.In-depth study of the catalytic mechanism on the surface of Ni-based catalysts can help to solve this problem.Based on the first-principles calculation method of density functional theory,the most favorable adsorption configuration of related species on Ni(111)in methane partial oxidation was determined,and the transition states of each element reaction in the reaction process were searched by the dimer method,and the whole process of methane partial oxidation on Ni(111)to CO was analyzed.The results show that the adsorption energy of CH*on Ni(111)is 6.98 eV,and the activation energy of CH2*dehydrogenation to CH*is 0.28 eV,which is much lower than that of CH*dehydrogenation(1.29 eV),indicating that CH*can exist in large quantities on the Ni surface,and its change can affect the whole reaction pathway.In the whole process of methane partial oxidation to CO,the activation energy of CH*to CO*oxidation by OH*is 1.48 eV,which is 0.11 eV lower than that of C*direct oxidation by O*to CO(1.59 eV),so the formation of OH*is more conducive to CO formation.In the process of oxidation of CH*by OH*to form CO*,the conversion process of CHOH*→ COH*→ CO*is undertaken,and the activation energy of the whole conversion process is 0.91 eV.The activation energy of the conversion procces(CHOH*→ CHO*→ CO*)is 0.73 eV,so CHOH*is more inclined to dehydrogenation to form CHO*and then CO*,and the optimal reaction path of methane partial oxidation to CO*is CH4*→ CH3*→ CH2*→ CH*+OH*→ CHOH*→ CHO*→ CO*.关键词
OH*/甲烷部分氧化/Ni(111)/密度泛函理论Key words
OH*/methane partial oxidation/Ni(111)/density functional theory分类
能源科技引用本文复制引用
陈鹏,孟园园,丁传敏,王俊文,王莲..OH*对Ni(111)上甲烷部分氧化成CO影响的理论计算[J].低碳化学与化工,2024,49(11):28-35,8.基金项目
国家自然科学基金(21978189,22308244) （21978189,22308244）
山西省自然科学基金面上项目(202203021221091). （202203021221091）
