Advanced Functional Materials: Molecular diffusion drives graphene film motion

With the depletion of fossil energy and the increasing environmental pollution, the energy issue has become a huge challenge for the current society. Compared with traditional production methods, it is more promising to obtain energy from fluids such as wind and water. However, such capacity methods often rely on large external equipment and corresponding environmental conditions, making their use subject to many restrictions. Therefore, the use of micro-devices to achieve energy conversion in fluids has begun to receive widespread attention from researchers.

Recently, the team of Fan Zhuangjun (communication author) of Harbin Engineering University realized the transformation of molecular diffusion energy into mechanical energy through the movement of graphene film driven by organic solution-water two-phase diffusion. This work prepared a graphene film with high hydrophobicity and unique micro-nano channels inside, which restricted the organic solution-water two-phase diffusion to one-way diffusion, and the unbalanced moment caused by this diffusion can make the graphene film (area: 2 cm2) Rotate quickly, up to 300 rpm. In addition, the work also achieved continuous rotation of the graphene film by continuous dropwise addition of ethanol, and promoted the linear motion of the magnetic boat by using the stacked graphene film. The mass of the magnetic boat (12 g) far exceeds the quality of the graphene film itself ( 33.5 mg). The significance of this work is to provide a new research approach to achieving clean, sustainable energy access. The related research “Molecular Diffusion-Driven Motion in 2D Graphene Film” was published on Advanced Functional Materials.

Figure 1 is a schematic diagram of the movement of graphene film driven by molecular diffusion

Advanced Functional Materials: Molecular diffusion drives graphene film motion

Figure 2 shows the morphology and performance of graphene film

Advanced Functional Materials: Molecular Diffusion Drives Graphene Membrane Motion

Diffusion-driven graphene film motion diagram (ac) graphene oxide slurry, graphene film coating process and Photographs

(d) Graphene films of different shapes

(e) Good bendability of graphene films

(f) Drawing of graphene films Stretch test curve

(g) SEM image of graphene film

(h) nitrogen adsorption and desorption curve of graphene film

(f)oxygen XRD patterns of graphene films and graphene films

Figure 3 is a study of the motion mechanism of graphene films

Advanced Functional Materials: Molecular Diffusion Drives Graphene Membrane Motion

(a) Random motion of graphene film on water surface

(b) Graphene Movement of the membrane below the water surface and at the water-air interface

(c) Schematic diagram of the diffusion of ethanol molecules adsorbed in the graphene film

(d) Graphene film for water and ethanol Wettability

(e) Graphene “Paper Crane”

Figure 4 is a graphene film rotation experiment

Advanced Functional Materials: Molecular Diffusion Drives Graphite

(a) Graphene film rotation demonstration

(b )Do not Rotational Velocity Comparison of Shape Graphene Films

(c) Schematic diagram of the driving mechanism of graphene film driven by unbalanced forces and moments

Figure 5 shows the rotational speed of graphene film by different factors Impact

Advanced Functional Materials: Molecular diffusion drives graphene film motion

(a Graphene film adsorption solution and rotation process demonstration

(b) Graphene film rotation speed with ethanol-water volume ratio curve

(c) Graphene film rotation speed varies with film thickness Curve

(d) Comparison of graphene film rotation speeds for different solutions

Figure 6 is a graphene film linear push and continuous rotation experiment

Advanced Functional Materials: Molecular diffusion can drive graphene film motion

(a) Schematic diagram of graphene film promoting linear motion of magnetic boat

(b) Schematic diagram of continuous rotation of graphene film by continuous dropwise addition of ethanol

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(c) Schematic diagram of light energy involved in achieving ethanol recycling and continuous rotation of graphene film

In this paper, molecules were discovered by preparing a two-dimensional graphene film with high hydrophobicity and internal micro-nano channels. The phenomenon of diffusion driving the movement of the graphene film realizes the conversion of molecular diffusion energy to mechanical energy. The unbalanced moment caused by molecular diffusion allows the graphene film to rotate at high speeds up to 300 rpm. In addition, the graphene film adsorbing the organic solution can also push the magnetic boat for linear motion. Therefore, this driving mechanism can be further applied to areas such as new capacity.

Documentation link: “Molecular Diffusion-Driven Motion in 2D Graphene Film” (Advanced Functional Materials. Doi.org/10.1002/adfm.201707053)

Source: Material People