Role of hydrogen in the dissociation of CH4 on different graphene by DFT study  

作　　者：Kun LI Hejun LI Ni LI Qiang SONG Lehua QI 

机构地区：[1]State Key Laboratory of Solidification Processing,Carbon/Carbon Composites Research Center,Northwestern Polytechnical University,Xi’an 710072,China [2]School of Aeronautics,Northwestern Polytechnical University,Xi’an 710072,China [3]School of Mechanical Engineering,Northwestern Polytechnical University,Xi’an 710072,China

出　　处：《Chinese Journal of Aeronautics》2022年第6期407-419,共13页中国航空学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos. 51821091, 51872234 and 51972271)

摘　　要：The effect of hydrogen on the growth mechanism of pyrocarbon has attracted much attention. The influence of hydrogen on the dissociation from CH4to C2H2on pristine graphene,N-doped graphene and vacancy graphene have been investigated by using density functional theory.There are two kinds of heterogeneous reaction pathways when the hydrogen is involved, i.e., dehydrogenation reactions and H-abstraction reactions. The transition state calculations were performed to acquire the reaction pathways on each substrate after obtaining the most stable adsorption configurations of the reactants and products. The results indicate that the adsorptions of reactants are not affected by hydrogen. The dehydrogenation reactions are more favored on vacancy graphene, and the H-abstraction reactions are more favored on the pristine graphene and N-doped graphene. The dehydrogenation reactions on the vacancy graphene are most favored among all these reactions in favor of the deposition of pyrocarbon. The dehydrogenation reactions on these three substrates are affected by hydrogen.

关 键 词：ABSTRACTION DEHYDROGENATION DFT GRAPHENE HYDROGEN Methane 

分 类 号：TB332[一般工业技术—材料科学与工程] V258.3[航空宇航科学与技术—航空宇航制造工程]