A representative arrangement of graphene flakes in ink-jet printed graphene...
A representative arrangement of graphene flakes in ink-jet printed graphene between two contacts (green). Color gradient corresponds to variation of flake potentials.
Source: University of Nottingham

How to 3D print novel electronic devices

The University of Nottingham has cracked the conundrum of how to use inks to 3D-print advanced electronic devices with useful properties, such as an ability to convert light into electricity. The study shows that it is possible to jet inks, containing tiny flakes of 2D materials such as graphene, to build up and mesh together the different layers of these complex, customised structures.

Using quantum mechanical modelling, the researchers also pinpointed how electrons move through the 2D material layers, to completely understand how the ground-breaking devices can be modified in future.

Co-author, Professor Mark Fromhold, Head of the School of Physics and Astronomy said, "By linking together fundamental concepts in quantum physics with state-of-the art-engineering, we have shown how complex devices for controlling electricity and light can be made by printing layers of material that are just a few atoms thick but centimetres across."

"According to the laws of quantum mechanics, in which the electrons act as waves rather than particles, we found electrons in 2D materials travel along complex trajectories between multiple flakes. It appears as if the electrons hop from one flake to another like a frog hopping between overlapping lily pads on the surface of a pond."

Two-dimensional materials like graphene are usually made by sequentially exfoliating a single layer of carbon atoms - arranged in a flat sheet - which are then used to produce bespoke structures. However, producing layers and combining them to make complex, sandwich-like materials has been difficult and usually required painstaking deposition of the layers one at a time and by hand.

Since its discovery, there has been an exponential growth in the number of patents involving graphene. However, in order to fully exploit its potential, scalable manufacturing techniques need to be developed.

The new paper shows that additive manufacturing - more commonly known as 3D printing - using inks, in which tiny flakes of graphene (a few billionths of a metre across) are suspended, provides a promising solution.

By combining advanced manufacturing techniques to make devices along with sophisticated ways of measuring their properties and quantum wave modelling the team worked out exactly how inkjet-printed graphene can successfully replace single layer graphene as a contact material for 2D metal semiconductors.

Recommended article

Co-author, Dr Lyudmila Turyanska from the Centre for Additive Manufacturing, said, "While 2D layers and devices have been 3D printed before, this is the first time anyone has identified how electrons move through them and demonstrated potential uses for the combined, printed layers. Our results could lead to diverse applications for inkjet-printed graphene-polymer composites and a range of other 2D materials. The findings could be employed to make a new generation of functional optoelectronic devices; for example, large and efficient solar cells; wearable, flexible electronics that are powered by sunlight or the motion of the wearer; perhaps even printed computers."

The researchers used a wide range of characterisation techniques - including micro-Raman spectroscopy (laser scanning), thermal gravity analysis, a novel 3D orbiSIMS instrument and electrical measurements - to provide detailed structural and functional understanding of inkjet-printed graphene polymers, and the effects of heat treating (annealing) on performance.

The next steps for the research are to better control the deposition of the flakes by using polymers to influence the way they arrange and align and trying different inks with a range of flake sizes. The researchers also hope to develop more sophisticated computer simulations of the materials and the way they work together, developing ways of mass-manufacturing they devices they prototype.

The study was published in Advanced Functional Materials.

Subscribe to our newsletter

Related articles

Graphene sensor detects ultrasensitive microwave

Graphene sensor detects ultrasensitive microwave

Researchers have developed ultrasensitive sensors that can detect microwaves with the highest theoretically possible sensitivity.

3D printed biomaterial enables forming of blood vessels

3D printed biomaterial enables forming of blood vessels

An international team of scientists have discovered a new material that can be 3D printed to create tissue-like vascular structures. In a new study, researchers have developed a way to 3D print graphene oxide with a protein which can organise into tubular structures that replicate some properties of vascular tissue.

Microrobots of metal and plastic

Microrobots of metal and plastic

Researchers have developed a technique for manufacturing micrometre-​long machines by interlocking multiple materials in a complex way.

3D printing strong and tough hydrogels

3D printing strong and tough hydrogels

Skin and cartilage are both strong and flexible – properties that are hard to replicate in artificial materials. But a new fabrication process brings lifelike synthetic polymers a step closer.

Using bacteria as micro-3D printers

Using bacteria as micro-3D printers

Researchers have used bacteria to produce intricately designed three-dimensional objects made of nanocellulose.

3D printing biomedical parts with supersonic speed

3D printing biomedical parts with supersonic speed

Researchers have developed a 3D printing technique that creates cellular metallic materials by smashing together powder particles at supersonic speed.

3D printed stents treat inflammation

3D printed stents treat inflammation

Researchers have produced biodegradable stents with esophageal-derived bioink to directly treat radiation esophagitis.

Aerogel: the micro structural material of the future

Aerogel: the micro structural material of the future

In a research-first, scientists from Empa were able to 3D print stable well-shaped microstructures made from silica aerogels for use in biotechnology and precision engineering.

An efficient way to create nanographene

An efficient way to create nanographene

Researchers have discovered a new way to create nanographene for power and display devices.

Popular articles