Tubular graphene architectures at the macroscopic scale: fabrication and properties

Abstract

Specific graphene architectures at the macroscopic scale are paramount for exploring new functions and practical uses of graphene. In this study, macroscopic, freestanding, and tubular graphene (TG) architectures were successfully fabricated through a versatile and robust process based on the annealing of cellulose acetate (CA) on Ni templates. These TG architectures can be obtained as woven tubes with diameters of approximately 50 μm; they possess high graphitic crystallinity, strong electrical conductivity, and favorable corrosion resistance. The effects of processing parameters, such as annealing temperature, annealing time, and amount of CA, on the graphene properties of these architectures were investigated and are discussed in this paper. The graphene properties were characterized through field emission scanning electron microscopy, high-resolution transmission electron microscopy, atomic force microscopy, Raman spectroscopy, four-point probe resistivity, and electrochemical measurements.

Edge-Rich Interconnected Graphene Mesh Electrode with High Electrochemical Reactivity Applicable for Glucose Detection

“…The graphene was directly grown on the Ni mesh template by a rapid thermal annealing of the solid carbon precursor (CA) at low vacuum. During the annealing procedure, dissociated carbon atoms diffused into the Ni template, and graphene precipitated onto the Ni surface during annealing and cooling [ 30 , 33 , 34 , 35 , 36 ]. After etching off Ni wires, only GM was left on the SiO 2 /Si substrate.…”

“…The graphene was grown on the Ni mesh template with a solid carbon precursor via a rapid thermal annealing approach as reported in previous works [ 30 , 33 , 34 , 35 , 36 ]. The Ni mesh template and cellulose acetate (CA) (C045A047A, Advantec Toyo, Japan) were first put together in the sample container of an infrared lamp annealing system (Mila 5000, Ulvac, Advance Riko, Japan) and then annealed at constant temperature of 850 °C for 8 min at a vacuum level of 0.6 Pa. A heating rate of 10 °C/s was applied to heat from room temperature to 850 °C.…”

Free-Standing, Interwoven Tubular Graphene Mesh-Supported Binary AuPt Nanocatalysts: An Innovative and High-Performance Anode Methanol Oxidation Catalyst

“…The catalyst supporting material TG meshes were prepared as followings. First, graphene-covered Ni (TG/Ni) meshes were fabricated via a thermal annealing method using cellulose acetate (CA) membrane (C045A047A, Advantec Toyo, Tokyo, Japan) as a solid carbon precursor with CA/Ni ratio of 1/4 in area; the experiment was processed at 950 °C for 8 min with heating rate of 15 °C/s under a low vacuum level of 0.4–0.8 × 10 −3 Torr by an infrared lamp annealing system (Mila 5000, Ulvac, Advance Riko, Yokohama, Japan) as reported in our previous works [ 29 , 30 , 31 , 32 , 33 , 34 ]. To protect the graphene structure, the TG/Ni meshes with an area of 2 × 2 cm 2 were immersed in a solution of poly (methyl methacrylate) (PMMA) diluted in acetone (V PMMA /V acetone = 1:2) for 30 min, then dried in a fume hood at 50 °C for 2 h.…”

“…Nevertheless, planar graphene sheets are easy to restack due to attractive force, and lead active surface area to be limited in two dimension (2D) [ 20 , 27 ]. On the other hand, reduced graphene oxide possesses a poor conductivity compared to chemical vapor deposition graphene [ 28 , 29 ], thus resulting in a degradation of electrochemical activity.…”

“…Our previous works [ 29 , 30 , 31 ] presented a free standing, flexible, and macroscopic interwoven tubular graphene (TG) mesh with superior surface area and excellent conductivity. In this work, the superior TG mesh was employed as a novel supporting material to decorate binary AuPt nanoparticles (NPs) for DMFCs.…”