Researchers use inkjet technology to 3D print graphene to produce electronic devices

China3D printingNet November 17th, graphene composed of single carbon atoms is considered to be a high-quality material with a wide range of applications due to its high strength, light weight, flexibility and unprecedented conductivity. However, mass production of large graphene parts remains a challenge.Previous research has shown that there are3D printingThere are various methods for graphene, but the size of these technologies is still limited. In addition, these methods and non-additive methods for producing large-area graphene layers hinder certain desirable properties of the material, namely conductivity.

Now, researchers at the University of Nottingham have developed a method that uses inkjet technology to perform3D printingGraphene technology, which can maintain the electrical properties of materials, thus opening up possibilities for a range of electronic components such as transistors and sensors. The research titled “Quantum Transport of Electrons and Holes between Sheets in Inkjet Printed Graphene Devices” was published in the journal Advanced Functional Materials.


3D printing
Phototransistor” alt=”A sort of
3D printing

Phototransistor “width=”620″ height=”472” />

A sort of3D printingThe phototransistor is formed by contacting the exfoliated InSe flakes with six ink-jet printed graphene strips (each electrode contains 5 printed layers and 7 lines) on a 300 nm SiO2/Si substrate. These strips Used as an electrode.”

As a two-dimensional material, graphene is usually made by peeling off the various layers of carob atoms in the form of a flat plate. Then, to process multilayer objects of this material, the plates need to be deposited manually, which is obviously a laborious process. In order to make full use of the characteristics of this exotic material through a scalable process, the Nottingham University team developed an inkjet method that can inkjet ink containing graphene flakes. In addition, by using quantum mechanical modeling, researchers can accurately understand how electrons move through the graphene layer, thereby controlling the electrical properties of the printed material.

Professor Mark Fromhold, Dean of the School of Physics and Astronomy and co-author of the paper, said:
“By linking the basic concepts in quantum physics with the latest technology, we have shown how to make complex devices for controlling electricity and light by printing layers of materials that are only a few atoms thick but a few centimeters wide. According to Quantum The law of mechanics, where electrons act as waves instead of particles, we find that electrons in two-dimensional materials travel along complex trajectories between multiple sheets. The electrons seem to jump from one sheet to another, like a frog overlapping on the surface of a pond Jumping between water lilies.”

In order to print the material, a graphene ink composed of graphene flakes and ethyl cellulose was dispersed into a cyclohexanone/terpineol mixture, and it was printed on a substrate using a drop-on-demand printing method. The layers were then annealed in a vacuum oven at 250°C to remove the solvent and decompose the additives in the ink. The research team found that the larger the number of layers, the lower the resistance. To demonstrate the possibility of this material, the team 3D printed a phototransistor composed of graphene electrodes on a semiconductor crystal.



Simulation of filling graphene flakes between two contacts.

The key to this research is to understand the movement of electrons in order to best produce graphene parts. To this end, the team modeled the conductive properties of the flake network within the printed part, and simulated the charge transfer between graphene flakes when a virtual voltage was applied to the simulation device.The author points out: “Our model reveals the transport mechanism of carriers in the printed graphene layer, and shows that to obtain a high-conductivity device, it is necessary to have a high[填充率]The optimized thickness of the printed layer. “

In order to understand how printed graphene works in devices made of multiple materials, the researchers printed field-effect transistors in 3D. Due to the interlayer ink mixing, the resistance is actually higher than the resistance of five graphene printed layers.


3D printing
Optical microscope image of graphene field effect transistor” alt=”
3D printing

Optical microscope image of graphene field effect transistor” width=”620″ height=”449″ />

3D printingOptical microscope image of a graphene field effect transistor; “The scale bar is 500 µm, and the spacing between the silver electrodes is 100 µm.”

China3D printingOnline reviews:Although the 2D layer and equipment used to be3D printingYes, but this is the first time anyone has determined how electrons move through them and has demonstrated the potential use of the combined printing layer. The results of this research may lead to various applications of inkjet-printed graphene-polymer composites and a series of other 2D materials.This discovery can be used to manufacture a new generation of functional optoelectronic devices. For example, large and efficient solar cells; wearable flexible electronic devices powered by sunlight or the wearer’s movement; and even printed computers. “

Next, the team plans to improve the deposition of graphene by using polymers to affect the way the flakes are arranged. They also hope to use different types of inks with graphene flakes of different sizes. Researchers will also improve their computer simulations to include how different materials work together. Ultimately, they aim to develop methods for mass production of prototype devices.

(Editor in charge: admin)