Carbon Monoxide Activation on Cobalt Carbide for Fischer-Tropsch Synthesis from First-Principles Theory

doi:10.1021/acscatal.9b00649

	Carbon Monoxide Activation on Cobalt Carbide for Fischer-Tropsch Synthesis from First-Principles Theory
	Chen, Pei-Pei 1,4; Liu, Jin-Xun 2; Li, Wei-Xue 3
刊名	ACS CATALYSIS
	2019-09-01
卷号	9 期号:9 页码:8093-8103
关键词	CO dissociation cobalt carbide phase diagram DFT calculation active phase Fischer-Tropsch synthesis
ISSN号	2155-5435
DOI	10.1021/acscatal.9b00649
通讯作者	Liu, Jin-Xun(jinxun@umich.edu) ; Li, Wei-Xue(wxli70@ustc.edu.cn)
英文摘要	Cobalt carbide based catalyst shows a promising activity and selectivity in the direct conversion of syngas (a mixture of carbon monoxide and hydrogen molecules) toward oxygenates and lower olefin. A mechanistic understanding of the cobalt carbide structure as well as its intrinsic reactivity under Fischer-Tropsch reaction conditions is vital but remains controversial. On the basis of ab initio thermodynamics and density functional theory (DFT) calculations, we study here a number of the pristine Co2C surfaces with different orientations and compositions as well as their catalytic activity on CO direct dissociation. The corresponding phase diagram and equilibrium morphology of Co2C under a wide range of the chemical potential of carbon are constructed. Under a higher chemical potential of carbon (carbon-rich conditions), carbon-rich surfaces like (110) and (111) facets are preferentially exposed surfaces, whereas at a lower chemical potential of carbon, the stoichiometric surfaces like (011) facet could appear. Cobalt-rich surfaces such as (101) and (010) facets could be exposed only due to the kinetics hindrance under carbon-poor or hydrogen-rich conditions where the pristine bulk carbide is thermodynamically not stable. It is found that though CO adsorbs strongly on stoichiometric and carbon-rich Co2C surfaces, the barrier for subsequent CO direct dissociation is significantly high. The presence of the carbon vacancy could promote CO direct dissociation. However, the high energy cost to produce the carbon vacancy for instance via methanation limits its overall activity toward CO activation. Implications of the present results on the role of Co2C in direct conversion of syngas toward oxygenates and lower olefin are discussed along with available experiments.
资助项目	National Key R&D Program of China[2017YFB0602205] ; Natural Science Foundation of China[91645202] ; Chinese Academy of Sciences[QYZDJ-SSW-SLH054]
WOS关键词	TOTAL-ENERGY CALCULATIONS ; IN-SITU XRD ; HIGHER ALCOHOLS ; LOWER OLEFINS ; CATALYTIC PERFORMANCE ; REALISTIC CONDITIONS ; MORPHOLOGY CONTROL ; CO ; SYNGAS ; SIZE
WOS研究方向	Chemistry
语种	英语
出版者	AMER CHEMICAL SOC
WOS记录号	WOS:000485090400042
资助机构	National Key R&D Program of China ; National Key R&D Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; National Key R&D Program of China ; National Key R&D Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; National Key R&D Program of China ; National Key R&D Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences ; National Key R&D Program of China ; National Key R&D Program of China ; Natural Science Foundation of China ; Natural Science Foundation of China ; Chinese Academy of Sciences ; Chinese Academy of Sciences
内容类型	期刊论文
源URL	[http://cas-ir.dicp.ac.cn/handle/321008/173294]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
通讯作者	Liu, Jin-Xun; Li, Wei-Xue
作者单位	1.Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Catalysis, Dalian 116023, Peoples R China 2.Univ Michigan, Dept Chem Engn, Ann Arbor, MI 48109 USA 3.Univ Sci & Technol China, CAS Ctr Excellence Nanosci, Hefei Natl Lab Phys Sci Microscale, Dept Chem Phys,iChEM, Hefei 230026, Anhui, Peoples R China 4.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Chen, Pei-Pei,Liu, Jin-Xun,Li, Wei-Xue. Carbon Monoxide Activation on Cobalt Carbide for Fischer-Tropsch Synthesis from First-Principles Theory[J]. ACS CATALYSIS,2019,9(9):8093-8103.
APA	Chen, Pei-Pei,Liu, Jin-Xun,&Li, Wei-Xue.(2019).Carbon Monoxide Activation on Cobalt Carbide for Fischer-Tropsch Synthesis from First-Principles Theory.ACS CATALYSIS,9(9),8093-8103.
MLA	Chen, Pei-Pei,et al."Carbon Monoxide Activation on Cobalt Carbide for Fischer-Tropsch Synthesis from First-Principles Theory".ACS CATALYSIS 9.9(2019):8093-8103.