Metal Catalysts for Layer-Exchange Growth of Multilayer Graphene

Nakajima, Yoshiki; Murata, Hiromasa; Saitoh, Noriyuki; Yoshizawa, Noriko; Suemasu, Takashi; Toko, Kaoru

doi:10.1021/acsami.8b14960

Cited by 26 publications

(35 citation statements)

References 55 publications

(100 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On top of the Mo 2 C (figure 4(c)), a graphitic layer was formed either during the anneal or after the segregation of C during the cooling phase. As claimed by Nakajima and co-authors, most likely the formation of the graphitic layer occurred during the annealing process [17]. a-C diffuses into Mo the layer and once the supersaturation of C is reached, the stable graphitic structures start nucleating on top of the formed Mo 2 C. 4(d)).…”

Section: Resultsmentioning

confidence: 78%

See 1 more Smart Citation

Growth of multi-layered graphene on molybdenum catalyst by solid phase reaction with amorphous carbon

Ricciardella¹,

Vollebregt²,

Kurganova³

et al. 2019

2D Mater.

View full text Add to dashboard Cite

A method to grow multi layers graphene (MLG) just by thermal annealing in an inert atmosphere is reported. A molybdenum (Mo) catalyst layer is used in combination with a solid amorphous carbon (a-C) source on top or below the Mo layer. The formation of MLG directly on top of the catalyst substrate surface is confirmed by Raman spectroscopy, atomic force microscopy, cross-section transmission electron microscopy, electron energy loss spectroscopy and x-ray photoelectron spectroscopy. Growth of MLG on top of the Mo catalyst is demonstrated both with a-C below and above the Mo layer. The growth mechanism is attributed to the diffusion of a-C through the Mo layer and precipitation into the graphene at the surface, similar to the growth by chemical vapour deposition (CVD) on a Ni catalyst. The role of the inert Ar/H 2 atmosphere, carbon thickness, catalyst thickness, anneal time and anneal temperature are reported. Fast growth of MLG (5 min) at 915 °C is demonstrated. The quality of MLG prepared by thermal annealing is at least as good as that of MLG synthesized by CVD. The relevant achievements presented in this study make the proposed technique a promising alternative to CVD based MLG.

show abstract

Section: Resultsmentioning

confidence: 78%

“…Only a few attempts for starting from solid state carbon precursors have been reported so far [15][16][17].…”

Section: Introductionmentioning

confidence: 99%

Growth of multi-layered graphene on molybdenum catalyst by solid phase reaction with amorphous carbon

Ricciardella¹,

Vollebregt²,

Kurganova³

et al. 2019

2D Mater.

View full text Add to dashboard Cite

show abstract

“…Such low metal contamination in the resulting layer is a typical feature of MILE, which is limited by solid solubility. 31…”

Section: Resultsmentioning

confidence: 99%

“…Such low metal contamination in the resulting layer is a typical feature of MILE, which is limited by solid solubility. 31 We investigated the detailed cross-sectional structure of the sample for n = 15 and t = 4 annealed at 600 °C. The crosssectional transmission electron microscopy (TEM) sample was prepared by the conventional focused ion beam method.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

Impact of Amorphous-C/Ni Multilayers on Ni-Induced Layer Exchange for Multilayer Graphene on Insulators

et al. 2019

Self Cite

View full text Add to dashboard Cite

Layer exchange growth of amorphous carbon (a-C) is a unique technique for fabricating high-quality multilayer graphene (MLG) on insulators at low temperatures. We investigated the effects of the a-C/Ni multilayer structure on the quality of MLG formed by Ni-induced layer exchange. The crystal quality and electrical conductivity of MLG improved dramatically as the number of a-C/Ni multilayers increased. A 600 °C-annealed sample in which 15 layers of 4-nm-thick a-C and 0.5-nm-thick Ni were laminated recorded an electrical conductivity of 1430 S/cm. This value is close to that of highly oriented pyrolytic graphite synthesized at approximately 3000 °C. This improvement is likely related to the bond weakening in a-C due to the screening effect of Ni. We expect that these results will contribute to low-temperature synthesis of MLG using a solid-phase reaction with metals.

show abstract

“…In turn, this carbide serves as a catalyst for graphene synthesis. Unlike carbon soluble metals, carbide formation limits the carbon back diffusion from the catalyst upon cooling resulting in uniform graphene synthesis [7][8][9]. Mo 2 C is a widely used catalyst among TMCs over the years for hydrogenation, water gas shift and methane reforming reactions due to its noble metal like catalytic activity, high temperature resistance and low cost [10][11][12][13] but the use of Mo 2 C on graphene synthesis is a relatively recent development [7,[14][15][16].…”

Section: Introductionmentioning

confidence: 99%

The role of pinhole structures in Mo thin films on multi-layer graphene synthesis

et al. 2020

View full text Add to dashboard Cite

In this study, the density and oxygen content of Mo thin films were varied by changing the deposition conditions, in order to understand their influence on the catalytic activity of Mo 2 C for the synthesis of multi-layer graphene (MLG). Structural and morphological analysis of Mo 2 C in relation to its catalytic activity indicate that the density of Mo plays a more critical role on MLG synthesis than the oxygen content. Results show that the pinholes present in relatively low density Mo layers act as catalytically active defect sites, promoting MLG synthesis. OPEN ACCESS RECEIVED

show abstract

Metal Catalysts for Layer-Exchange Growth of Multilayer Graphene

Cited by 26 publications

References 55 publications

Growth of multi-layered graphene on molybdenum catalyst by solid phase reaction with amorphous carbon

Growth of multi-layered graphene on molybdenum catalyst by solid phase reaction with amorphous carbon

Impact of Amorphous-C/Ni Multilayers on Ni-Induced Layer Exchange for Multilayer Graphene on Insulators

The role of pinhole structures in Mo thin films on multi-layer graphene synthesis

Contact Info

Product

Resources

About