高等学校化学学报2024，Vol.45Issue(7)：101-110,10.DOI:10.7503/cjcu20240038
石墨烯负载单原子Mo上合成气催化转化机理:碳组分和Mo-C作用的影响
Mechanism upon Conversion of Syngas Catalyzed by Single Atom Mo Supported on Graphene:Role of Carbon Component and Impact from Mo-C Interactions
摘要
Abstract
The catalytic behaviors of metal for syngas conversion are related to the carbonization of the metal,however,the formed metallic carbides are of complicated composition and structures,making the identification of the active phase of the catalysts be challengeable,so it is significant to investigate the role of the carbon component of the catalysts.In this work,we studied computationally mechanisms of syngas conversion to alcohols on single atom Mo supported on pristine graphene(Mo/pri-graphene)and single-carbon vacant graphene(Mo/sv-graphene)by means of density functional theory(DFT)method to explore the regulated effect of carbon component on C—O activation.The results show that it is significantly different for mechanisms of syngas conversion on Mo/pri-graphene with weak Mo-C interactions and Mo/sv-graphene with strong Mo-C interactions.On Mo/pri-graphene the preferred pathway is CO→HCO→CH2O→CH3O→CH3/CH4,and species CH3O is of some stability due to high activation free energy of its further transformation into CH3/CH4,while on Mo/sv-graphene the preferred pathway is CO→HCO→CH2O→CH2OH→CH3OH/CH3(CH4),and the coexistence of species CH3OH and CH3(CH4)provides a possibility for the following carbon chain propagation.The activation free energy of the elementary steps of CO hydrogenation on Mo/sv-graphene is generally lower than that on Mo/pri-graphene.The reasons are the lower interactions between Mo/sv-graphene and the substrate,and the participation of the carbon component of Mo/sv-graphene during the activation/transformation of the substrate.Thus,the carbon component of catalysts can regulate(and/or take participate in)the interaction of the catalysts with the substrates,and then make an improvement on the activity and selectivity.关键词
单原子/钼/石墨烯/合成气转化/碳/反应机理Key words
Single atom/Mo/graphene/Syngas conversion/Carbon/Mechanism分类
化学化工引用本文复制引用
孔雪,张海平,夏文生,张庆红,万惠霖..石墨烯负载单原子Mo上合成气催化转化机理:碳组分和Mo-C作用的影响[J].高等学校化学学报,2024,45(7):101-110,10.基金项目
国家重点研发计划项目(批准号:2019YFE04400)和教育部创新团队发展计划项目(批准号:IRT1036)资助.Supported by the National Key Research and Development Plan Project,China(No.2019YFE04400)and the Ministry of Education Innovation Team Development Program Project,China(No.IRT1036). （批准号:2019YFE04400）
