Kinetic Evidence of Most Abundant Surface Intermediates Variation over Pt-n and Pt-p: Few-Atom Pt Ensembles Enable Efficient Catalytic Cyclohexane Dehydrogenation for Hydrogen Production-II

doi:10.1021/acscatal.2c01420

IMR OpenIR

	Kinetic Evidence of Most Abundant Surface Intermediates Variation over Pt-n and Pt-p: Few-Atom Pt Ensembles Enable Efficient Catalytic Cyclohexane Dehydrogenation for Hydrogen Production-II
	Guo, Jinqiu 1,2; Peng, Mi 3,4; Jia, Zhimin 5,6; Li, Chengyu 3,4; Liu, Hongyang 5,6; Zhang, Hongbo 1,2; Ma, Ding 3,4
通讯作者	Zhang, Hongbo(hbzhang@nankai.edu.cn) ; Ma, Ding(dma@pku.edu.cn)
	2022-06-17
发表期刊	ACS CATALYSIS
ISSN	2155-5435
卷号	12 期号:12 页码:7248-7261
摘要	C-H bond activation is very important in upgrading of alkanes or aromatics into value-added products, such as alkenes or even oxygen ates, etc., during natural gas utilization and hydrogen transportation via chemical strategies. Because of the low polarization ability and high bond energies of the C-H bonds within the hydrocarbons, the selective C-H bond activation suffers from low efficiency for a long time and requests systematic work on understanding the reaction mechanisms, in which the kinetic studies are highly desired and not well understood in a comprehensive manner. Herein, a universal kinetic model has been established to explain the entire reaction process of C-H bond activation for cyclohexane dehydrogenation (CDH) over various structures of Pt (cluster: Pt-n and partide: Pt-p) decorated nanodiamond@graphene (Pt-x/ND@G) nanocomposite with specific emphasis on the elementary steps, the rate-determining step(s) (RDS), and the most abundant surface intermediates (MASIs). With the combination of kinetic and thermodynamic measurements, it was found that cyclohexane dehydrogenation shows different reaction mechanisms over Pt-n catalysts, compared to Pt-p catalysts. And C6H12 dehydrogenation rates showed nearly first-order (Pt-n:r(DH) similar to [C6H12](similar to 0.6); Pt-p: r(DH) [C6H12](similar to 1.0)) dependence on the C6H12, while the orders of H, are obviously different over the two catalysts, in which the addition of H-2 shows negligible effect (nearly zero-order) once a trace amount of H2( )is introduced, and then obviously promotes (nearly secondorder) dehydrogenation over Pt-n (Pt-n: r(DH)similar to [H-2](similar to 0-2)), while the dehydrogenation rate over Pt-p is prominently inhibited by adding x H2 to the catalytic system under similar reaction conditions (Pt-p: r(DH )(similar to )[H-2](similar to-)(10-0)) , thus indicating that Pt-n and Pt-p, catalysts have diverse MASIs, which is further supported by the developed universal kinetic model of dehydrogenation. That perfectly explains the relationship between the dehydrogenation events and the coverage of surface hydrogen species. The predicted reaction process following a Langmuir-Hinshelwood model that matches the experimental configurations very well, suggesting that the first C-H bond rupture of C6H12 is probably the RDS for both Pt-n and Pt-p, catalysts, while the MASIs varied from C6H10* to H* explained the diversities of the H-2 dependencies between Pt-n and Pt-p catalysts systematically. This kinetic case study as well as the established universal model could be easily extended to some other systems related to C-H bond rupture and attracts the attention on exploring the correlations between nanostructure and the reaction performance.
关键词	cyclohexane dehydrogenation H-2 dependencies most abundant surface intermediates rate-determining step universal model parity plots
资助者	111 Project of China ; Haihe Laboratory of Sustainable Chemical Transformations ; Nankai University ; National Natural Science Foundation of China
DOI	10.1021/acscatal.2c01420
收录类别	SCI
语种	英语
资助项目	111 Project of China[B18030] ; Haihe Laboratory of Sustainable Chemical Transformations ; Nankai University ; National Natural Science Foundation of China[22172078]
WOS研究方向	Chemistry
WOS类目	Chemistry, Physical
WOS记录号	WOS:000813506400001
出版者	AMER CHEMICAL SOC
引用统计	被引频次：4[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/174716
专题	中国科学院金属研究所
通讯作者	Zhang, Hongbo; Ma, Ding
作者单位	1.Nankai Univ, Sch Mat Sci & Engn, Tianjin 300350, Peoples R China 2.Haihe Lab Sustainable Chem Transformat, Tianjin 300350, Peoples R China 3.Peking Univ, Beijing Natl Lab Mol Sci, Coll Chem & Mol Engn, Beijing 100871, Peoples R China 4.Peking Univ, BIC ESAT, Beijing 100871, Peoples R China 5.Univ Sci & Technol China, Sch Mat Sci & Engn, Hefei 230026, Peoples R China 6.Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China
推荐引用方式 GB/T 7714	Guo, Jinqiu,Peng, Mi,Jia, Zhimin,et al. Kinetic Evidence of Most Abundant Surface Intermediates Variation over Pt-n and Pt-p: Few-Atom Pt Ensembles Enable Efficient Catalytic Cyclohexane Dehydrogenation for Hydrogen Production-II[J]. ACS CATALYSIS,2022,12(12):7248-7261.
APA	Guo, Jinqiu.,Peng, Mi.,Jia, Zhimin.,Li, Chengyu.,Liu, Hongyang.,...&Ma, Ding.(2022).Kinetic Evidence of Most Abundant Surface Intermediates Variation over Pt-n and Pt-p: Few-Atom Pt Ensembles Enable Efficient Catalytic Cyclohexane Dehydrogenation for Hydrogen Production-II.ACS CATALYSIS,12(12),7248-7261.
MLA	Guo, Jinqiu,et al."Kinetic Evidence of Most Abundant Surface Intermediates Variation over Pt-n and Pt-p: Few-Atom Pt Ensembles Enable Efficient Catalytic Cyclohexane Dehydrogenation for Hydrogen Production-II".ACS CATALYSIS 12.12(2022):7248-7261.