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Femtosecond laser rapid fabrication of large-area rose-like micropatterns on freestanding flexible graphene films.

Shi X, Li X, Jiang L, Qu L, Zhao Y, Ran P, Wang Q, Cao Q, Ma T, Lu Y - Sci Rep (2015)

Bottom Line: This unique hierarchical layering structure of graphene films provides great possibilities for generation of tensile stress during femtosecond laser ablation to roll up the nanoflakes, which contributes to the formation of microflowers.More importantly, this technique enables fabrication of the large-area patterned surfaces at centimeter scales in a simple and efficient way.This study not only presents new insights of ultrafast laser processing of novel graphene-based materials but also shows great promise of designing new materials combined with ultrafast laser surface patterning for future applications in functional coatings, sensors, actuators and microfluidics.

View Article: PubMed Central - PubMed

Affiliation: Laser Micro/Nano Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, PR China.

ABSTRACT
We developed a simple, scalable and high-throughput method for fabrication of large-area three-dimensional rose-like microflowers with controlled size, shape and density on graphene films by femtosecond laser micromachining. The novel biomimetic microflower that composed of numerous turnup graphene nanoflakes can be fabricated by only a single femtosecond laser pulse, which is efficient enough for large-area patterning. The graphene films were composed of layer-by-layer graphene nanosheets separated by nanogaps (~10-50 nm), and graphene monolayers with an interlayer spacing of ~0.37 nm constituted each of the graphene nanosheets. This unique hierarchical layering structure of graphene films provides great possibilities for generation of tensile stress during femtosecond laser ablation to roll up the nanoflakes, which contributes to the formation of microflowers. By a simple scanning technique, patterned surfaces with controllable densities of flower patterns were obtained, which can exhibit adhesive superhydrophobicity. More importantly, this technique enables fabrication of the large-area patterned surfaces at centimeter scales in a simple and efficient way. This study not only presents new insights of ultrafast laser processing of novel graphene-based materials but also shows great promise of designing new materials combined with ultrafast laser surface patterning for future applications in functional coatings, sensors, actuators and microfluidics.

No MeSH data available.


Schematics illustration of the procedures to produce the graphene film for surface patterning using femtosecond laser pulses.(a) Graphene oxide sheets. (b) Reduced graphene sheets. (c) Graphene film by filtration of reduced graphene sheets. (d) A graphene microflower produced with a single laser pulse at fluence of 1.1 J/cm2. (e) Large-area surface patterning by fs laser direct writing. (f) Large-area uniform flower patterns on the surface of a graphene film. Digital image of the pristine (left) and engineered surfaces (right, darker black) showing totally different surface wettability.
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f1: Schematics illustration of the procedures to produce the graphene film for surface patterning using femtosecond laser pulses.(a) Graphene oxide sheets. (b) Reduced graphene sheets. (c) Graphene film by filtration of reduced graphene sheets. (d) A graphene microflower produced with a single laser pulse at fluence of 1.1 J/cm2. (e) Large-area surface patterning by fs laser direct writing. (f) Large-area uniform flower patterns on the surface of a graphene film. Digital image of the pristine (left) and engineered surfaces (right, darker black) showing totally different surface wettability.

Mentions: Figure 1 schematically illustrates the procedures to obtain large-area biomimetic micropatterns on graphene films. The graphene films were prepared by direct filtration of aqueous reduced graphene oxide colloidal suspensions through a filter membrane as detailed in our previous report27. After irradiation with a single laser pulse, a rose-like graphene microflower could be obtained in the ablated region, as shown in Fig. 1d. The laser beam was then scanned with coordinated adjustment of laser repetition rate, scanning speed (v), and scanning pitch (Fig. 1e). By moving the stage with respect to the laser beam, large-area arrays of biomimetic graphene microflowers with tunable densities were directly written (Fig. 1f). The patterned graphene area (3 × 3 mm2) shows superhydrophobility with a large water contact angle of 150°, whereas the original graphene film only exhibits hydrophilicity with a low water contact angle of 78° (Fig. 1f).


Femtosecond laser rapid fabrication of large-area rose-like micropatterns on freestanding flexible graphene films.

Shi X, Li X, Jiang L, Qu L, Zhao Y, Ran P, Wang Q, Cao Q, Ma T, Lu Y - Sci Rep (2015)

Schematics illustration of the procedures to produce the graphene film for surface patterning using femtosecond laser pulses.(a) Graphene oxide sheets. (b) Reduced graphene sheets. (c) Graphene film by filtration of reduced graphene sheets. (d) A graphene microflower produced with a single laser pulse at fluence of 1.1 J/cm2. (e) Large-area surface patterning by fs laser direct writing. (f) Large-area uniform flower patterns on the surface of a graphene film. Digital image of the pristine (left) and engineered surfaces (right, darker black) showing totally different surface wettability.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4663466&req=5

f1: Schematics illustration of the procedures to produce the graphene film for surface patterning using femtosecond laser pulses.(a) Graphene oxide sheets. (b) Reduced graphene sheets. (c) Graphene film by filtration of reduced graphene sheets. (d) A graphene microflower produced with a single laser pulse at fluence of 1.1 J/cm2. (e) Large-area surface patterning by fs laser direct writing. (f) Large-area uniform flower patterns on the surface of a graphene film. Digital image of the pristine (left) and engineered surfaces (right, darker black) showing totally different surface wettability.
Mentions: Figure 1 schematically illustrates the procedures to obtain large-area biomimetic micropatterns on graphene films. The graphene films were prepared by direct filtration of aqueous reduced graphene oxide colloidal suspensions through a filter membrane as detailed in our previous report27. After irradiation with a single laser pulse, a rose-like graphene microflower could be obtained in the ablated region, as shown in Fig. 1d. The laser beam was then scanned with coordinated adjustment of laser repetition rate, scanning speed (v), and scanning pitch (Fig. 1e). By moving the stage with respect to the laser beam, large-area arrays of biomimetic graphene microflowers with tunable densities were directly written (Fig. 1f). The patterned graphene area (3 × 3 mm2) shows superhydrophobility with a large water contact angle of 150°, whereas the original graphene film only exhibits hydrophilicity with a low water contact angle of 78° (Fig. 1f).

Bottom Line: This unique hierarchical layering structure of graphene films provides great possibilities for generation of tensile stress during femtosecond laser ablation to roll up the nanoflakes, which contributes to the formation of microflowers.More importantly, this technique enables fabrication of the large-area patterned surfaces at centimeter scales in a simple and efficient way.This study not only presents new insights of ultrafast laser processing of novel graphene-based materials but also shows great promise of designing new materials combined with ultrafast laser surface patterning for future applications in functional coatings, sensors, actuators and microfluidics.

View Article: PubMed Central - PubMed

Affiliation: Laser Micro/Nano Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, PR China.

ABSTRACT
We developed a simple, scalable and high-throughput method for fabrication of large-area three-dimensional rose-like microflowers with controlled size, shape and density on graphene films by femtosecond laser micromachining. The novel biomimetic microflower that composed of numerous turnup graphene nanoflakes can be fabricated by only a single femtosecond laser pulse, which is efficient enough for large-area patterning. The graphene films were composed of layer-by-layer graphene nanosheets separated by nanogaps (~10-50 nm), and graphene monolayers with an interlayer spacing of ~0.37 nm constituted each of the graphene nanosheets. This unique hierarchical layering structure of graphene films provides great possibilities for generation of tensile stress during femtosecond laser ablation to roll up the nanoflakes, which contributes to the formation of microflowers. By a simple scanning technique, patterned surfaces with controllable densities of flower patterns were obtained, which can exhibit adhesive superhydrophobicity. More importantly, this technique enables fabrication of the large-area patterned surfaces at centimeter scales in a simple and efficient way. This study not only presents new insights of ultrafast laser processing of novel graphene-based materials but also shows great promise of designing new materials combined with ultrafast laser surface patterning for future applications in functional coatings, sensors, actuators and microfluidics.

No MeSH data available.