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High-speed roll-to-roll manufacturing of graphene using a concentric tube CVD reactor.

Polsen ES, McNerny DQ, Viswanath B, Pattinson SW, John Hart A - Sci Rep (2015)

Bottom Line: We show that a smooth isothermal transition between the reducing and carbon-containing atmospheres, enabled by injection of the carbon feedstock via radial holes in the inner tube, is essential to high-quality roll-to-roll graphene CVD.We discuss how the foil quality and microstructure limit the uniformity of graphene over macroscopic dimensions.We conclude by discussing means of scaling and reconfiguring the CTCVD design based on general requirements for 2-D materials manufacturing.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Engineering, University of Michigan, 2350 Hayward St., Ann Arbor, MI 48109, USA.

ABSTRACT
We present the design of a concentric tube (CT) reactor for roll-to-roll chemical vapor deposition (CVD) on flexible substrates, and its application to continuous production of graphene on copper foil. In the CTCVD reactor, the thin foil substrate is helically wrapped around the inner tube, and translates through the gap between the concentric tubes. We use a bench-scale prototype machine to synthesize graphene on copper substrates at translation speeds varying from 25 mm/min to 500 mm/min, and investigate the influence of process parameters on the uniformity and coverage of graphene on a continuously moving foil. At lower speeds, high-quality monolayer graphene is formed; at higher speeds, rapid nucleation of small graphene domains is observed, yet coalescence is prevented by the limited residence time in the CTCVD system. We show that a smooth isothermal transition between the reducing and carbon-containing atmospheres, enabled by injection of the carbon feedstock via radial holes in the inner tube, is essential to high-quality roll-to-roll graphene CVD. We discuss how the foil quality and microstructure limit the uniformity of graphene over macroscopic dimensions. We conclude by discussing means of scaling and reconfiguring the CTCVD design based on general requirements for 2-D materials manufacturing.

No MeSH data available.


Concentric tube CVD (CTCVD) system configured for R2R graphene growth on Cu foil. a) System schematic showing the helical feed path (left to right), sequential treatment zones, and internal gas injection holes. b) Cross-section view of the concentric tube arrangement. c) Bench-scale prototype of the CTCVD system (setup where processing is right to left), with rails for alignment with tube furnace. d) Close-up of e), showing the gas injection holes used to supply the hydrocarbon gas to the downstream treatment zone. e) Top view of a Cu foil substrate wrapped through the system.
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f1: Concentric tube CVD (CTCVD) system configured for R2R graphene growth on Cu foil. a) System schematic showing the helical feed path (left to right), sequential treatment zones, and internal gas injection holes. b) Cross-section view of the concentric tube arrangement. c) Bench-scale prototype of the CTCVD system (setup where processing is right to left), with rails for alignment with tube furnace. d) Close-up of e), showing the gas injection holes used to supply the hydrocarbon gas to the downstream treatment zone. e) Top view of a Cu foil substrate wrapped through the system.

Mentions: In the concentric tube (CT) CVD reactor design (Fig. 1a–b), the substrate continuously translates in a helical path, as it is wrapped onto the surface of a quartz tube placed concentrically within another quartz tube. The heated reactor volume is therefore defined by the annular gap between the tubes and the length over which the system is heated. Compared to a single tube reactor design with equivalent outer diameter, the rationale for the CTCVD configuration is to reduce the volume of gas required for processing, establish flow uniformity via the small gap between the tubes, and enable the size of the treatment zone to be adjusted without changing the flow profile over the substrate. The prototype CTCVD system is built using a standard tube furnace (Lindberg Blue M Mini-Mite, single 30cm long heated zone), and the end chambers contain web-handling mechanisms built largely using commercial-off-the-shelf components (Fig. 1c–e). The use of tubes with circular cross section is desirable for low-pressure operation and sealing using conventional vacuum components, while the annular reactor geometry captures the geometric advantage of a thin cross-section.


High-speed roll-to-roll manufacturing of graphene using a concentric tube CVD reactor.

Polsen ES, McNerny DQ, Viswanath B, Pattinson SW, John Hart A - Sci Rep (2015)

Concentric tube CVD (CTCVD) system configured for R2R graphene growth on Cu foil. a) System schematic showing the helical feed path (left to right), sequential treatment zones, and internal gas injection holes. b) Cross-section view of the concentric tube arrangement. c) Bench-scale prototype of the CTCVD system (setup where processing is right to left), with rails for alignment with tube furnace. d) Close-up of e), showing the gas injection holes used to supply the hydrocarbon gas to the downstream treatment zone. e) Top view of a Cu foil substrate wrapped through the system.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4440526&req=5

f1: Concentric tube CVD (CTCVD) system configured for R2R graphene growth on Cu foil. a) System schematic showing the helical feed path (left to right), sequential treatment zones, and internal gas injection holes. b) Cross-section view of the concentric tube arrangement. c) Bench-scale prototype of the CTCVD system (setup where processing is right to left), with rails for alignment with tube furnace. d) Close-up of e), showing the gas injection holes used to supply the hydrocarbon gas to the downstream treatment zone. e) Top view of a Cu foil substrate wrapped through the system.
Mentions: In the concentric tube (CT) CVD reactor design (Fig. 1a–b), the substrate continuously translates in a helical path, as it is wrapped onto the surface of a quartz tube placed concentrically within another quartz tube. The heated reactor volume is therefore defined by the annular gap between the tubes and the length over which the system is heated. Compared to a single tube reactor design with equivalent outer diameter, the rationale for the CTCVD configuration is to reduce the volume of gas required for processing, establish flow uniformity via the small gap between the tubes, and enable the size of the treatment zone to be adjusted without changing the flow profile over the substrate. The prototype CTCVD system is built using a standard tube furnace (Lindberg Blue M Mini-Mite, single 30cm long heated zone), and the end chambers contain web-handling mechanisms built largely using commercial-off-the-shelf components (Fig. 1c–e). The use of tubes with circular cross section is desirable for low-pressure operation and sealing using conventional vacuum components, while the annular reactor geometry captures the geometric advantage of a thin cross-section.

Bottom Line: We show that a smooth isothermal transition between the reducing and carbon-containing atmospheres, enabled by injection of the carbon feedstock via radial holes in the inner tube, is essential to high-quality roll-to-roll graphene CVD.We discuss how the foil quality and microstructure limit the uniformity of graphene over macroscopic dimensions.We conclude by discussing means of scaling and reconfiguring the CTCVD design based on general requirements for 2-D materials manufacturing.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Engineering, University of Michigan, 2350 Hayward St., Ann Arbor, MI 48109, USA.

ABSTRACT
We present the design of a concentric tube (CT) reactor for roll-to-roll chemical vapor deposition (CVD) on flexible substrates, and its application to continuous production of graphene on copper foil. In the CTCVD reactor, the thin foil substrate is helically wrapped around the inner tube, and translates through the gap between the concentric tubes. We use a bench-scale prototype machine to synthesize graphene on copper substrates at translation speeds varying from 25 mm/min to 500 mm/min, and investigate the influence of process parameters on the uniformity and coverage of graphene on a continuously moving foil. At lower speeds, high-quality monolayer graphene is formed; at higher speeds, rapid nucleation of small graphene domains is observed, yet coalescence is prevented by the limited residence time in the CTCVD system. We show that a smooth isothermal transition between the reducing and carbon-containing atmospheres, enabled by injection of the carbon feedstock via radial holes in the inner tube, is essential to high-quality roll-to-roll graphene CVD. We discuss how the foil quality and microstructure limit the uniformity of graphene over macroscopic dimensions. We conclude by discussing means of scaling and reconfiguring the CTCVD design based on general requirements for 2-D materials manufacturing.

No MeSH data available.