Iron Clusters Embedded in Graphene Nanocavities: Heat-Induced Structural Evolution and Catalytic C-C Bond Breaking
文献类型：期刊论文
| 作者 | Chen, S; Bie, J; Fa, W; Zha, YC; Gao, Y; Zeng, XC |
| 刊名 | ACS APPLIED NANO MATERIALS
 |
| 出版日期 | 2019 |
| 卷号 | 2期号:1页码:535—545 |
| 关键词 | METAL TRANSITION GROWTH NANORIBBONS MEMBRANES |
| ISSN号 | 2574-0970 |
| DOI | 10.1021/acsanm.8b02104 |
| 文献子类 | 期刊论文 |
| 英文摘要 | Metal nanoclusters can be anchored at defective sites of graphene sheets to strengthen their thermal stability for potential device applications. A previous transmission electron microscopy (TEM) experimental study on the morphology change of an ultrafine iron cluster embedded in a graphene nanocavity suggests that the underlying reaction mechanism is likely due to solid-solid transformation [Sci. Rep. 2012, 2, 995]. The morphology change of the Fe cluster may also assist the enlargement of the graphene nanocavity. This TEM experiment reminds us that if the anchoring Fe nanocluster within the graphene nanocavity can efficiently catalyze graphene etching at a certain operation temperature, the device application of graphene-metal nanocluster composites would be largely limited. Herein, we have performed ab initio molecular dynamics (AIMD) simulations of a triangular hexagonal close-packed (HCP) Fe-53 cluster in contact with either the edge of the graphene nanocavity or graphene nanoribbon to investigate its structural evolution and catalytic behavior at an elevated temperature (1173 K). Contrary to the previous TEM experiment, we suggest an alternative reaction mechanism, namely, the melting recrystallization for the structural transformation of Fe cluster. Moreover, we find that the molten iron cluster can etch and enlarge the graphene nanocavity. At the high temperature of 1173 K without H and O atoms, the Fe 53 cluster undergoes a phase transition from the HCP structure to a liquid-like nanodroplet while in contact with the edge of either graphene nanocavity or graphene nanoribbon. Interestingly, the Fe 53 cluster tends to saturate the graphene edges via forming Fe-C bonds but without breaking any C-C bonds within the time scale of AIMD simulations. Our reactive MD simulations show that the HCP Fe 53 cluster can complete with the reaction of carbide formation within 10 ps. Independent climbing-image nudged elastic band calculations offer additional insight into the Fe-catalyzed reaction mechanism of C-C bond dissociation, C-C displacement, or C-C rotation during graphene etching. We find that the Fe cluster can only efficiently catalyze the C-C dissociation at the armchair edge, following the C-C displacement mechanism, because of the formation of strong bonds between Fe and dangling C atoms. We also find that the catalytic ability of Fe atoms seems less effective compared with that of Ni atoms, in part because Fe clusters tend to change their shapes during the reaction. Lastly, we perform AIMD simulations of the Fe-53 cluster in contact with smaller-sized sp(2)-C flakes. We observe that the cluster can soak the carbon flake on its surface, followed by breaking the C-C bonds through C-C displacement or C-C rotation. It appears that the catalytic ability of the Fe-53 cluster that is in contact with graphene C atoms depends on the size of the carbon species. |
| 语种 | 英语 |
| 源URL | [http://ir.sinap.ac.cn/handle/331007/31684]  |
| 专题 | 上海应用物理研究所_中科院上海应用物理研究所2011-2017年 |
| 作者单位 | 1.Nanjing Univ, Kuang Yaming Honors Sch, Nanjing 210023, Jiangsu, Peoples R China; 2.Nanjing Univ, Natl Lab Solid State Microstruct, Nanjing 210093, Jiangsu, Peoples R China; 3.Nanjing Univ, Dept Phys, Nanjing 210093, Jiangsu, Peoples R China; 4.Chinese Acad Sci, Shanghai Inst Appl Phys, Div Interfacial Water, Shanghai 201800, Peoples R China; 5.Chinese Acad Sci, Shanghai Inst Appl Phys, Key Lab Interfacial Phys & Technol, Shanghai 201800, Peoples R China; 6.Univ Nebraska, Dept Chem, Lincoln, NE 68588 USA; 7.Univ Nebraska, Dept Chem & Biomol Engn, Lincoln, NE 68588 USA; 8.Univ Nebraska, Dept Mech & Mat Engn, Lincoln, NE 68588 USA |
| 推荐引用方式 GB/T 7714 | Chen, S,Bie, J,Fa, W,et al. Iron Clusters Embedded in Graphene Nanocavities: Heat-Induced Structural Evolution and Catalytic C-C Bond Breaking[J]. ACS APPLIED NANO MATERIALS,2019,2(1):535—545. |
| APA | Chen, S,Bie, J,Fa, W,Zha, YC,Gao, Y,&Zeng, XC.(2019).Iron Clusters Embedded in Graphene Nanocavities: Heat-Induced Structural Evolution and Catalytic C-C Bond Breaking.ACS APPLIED NANO MATERIALS,2(1),535—545. |
| MLA | Chen, S,et al."Iron Clusters Embedded in Graphene Nanocavities: Heat-Induced Structural Evolution and Catalytic C-C Bond Breaking".ACS APPLIED NANO MATERIALS 2.1(2019):535—545. |
入库方式： OAI收割
来源：上海应用物理研究所
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