Flexible

A new study, led by the Catalan Institute of Nanoscience and Nanotechnology (ICN2) along with the Universitat Autònoma de Barcelona (UAB) and other international partners like the University of Manchester (under the European Graphene Flagship project), presents EGNITE (Engineered Graphene for Neural Interfaces) - a novel class of flexible, high-resolution, high-precision graphene-based implantable neurotechnology with the potential for a transformative impact in neuroscience and medical applications. 

This work aims to deliver an innovative technology to the growing field of neuroelectronics and brain-computer interfaces. EGNITE builds on the experience of its inventors in fabrication and medical translation of carbon nanomaterials. This innovative technology based on nanoporous graphene integrates fabrication processes standard in the semiconductor industry to assemble graphene microelectrodes of a mere 25 µm in diameter. The graphene microelectrodes exhibit low impedance and high charge injection, essential attributes for flexible and efficient neural interfaces.

Researchers from Korea's Seoul National University and Sungkyunkwan University recently developed a method to grow GaN LED arrays on a flexible graphene layer. The so-called microdisk arrays exhibit excellent crystallinity with a uniform in-plane orientation and strong blue light emission.

Flexible GaN-microLEDs on graphene, Seoul National University, Sungkyunkwan University

The researchers grew the GaN microdisks on a graphene layer (grown on a sapphire substrate) covered with a micro-patterned SiO₂ mask using metal–organic vapor-phase epitaxy. The microdisks were then processed into micro-LEDs and then successfully transferred onto bendable substrates.

An interdisciplinary research team of the Research Training Group (RTG) 2154 "Materials for Brain" at Kiel University (CAU) has developed a method to produce graphene-enhanced hydrogels with an excellent level of electrical conductivity. What makes this method special is that the mechanical properties of the hydrogels are largely retained. The material is said to have potential for medical functional implants, for example, and other medical applications.

"Graphene has outstanding electrical and mechanical properties and is also very light," says Dr. Fabian Schütt, junior group leader in the Research Training Group, thus emphasizing the advantages of the ultra-thin material, which consists of only one layer of carbon atoms. What makes this new method different is the amount of graphene used. "We are using significantly less graphene than previous studies, and as a result, the key properties of the hydrogel are retained," says Schütt about the current study, which he initiated.

A research team from the Korea Institute of Science and Technology (KIST) recently developed a graphene-based lithium-ion battery that is flexible enough to be stretched.

Dr. Jeong Gon Son's research team at the Photo-Electronic Hybrids Research Center at the Korea Institute of Science and Technology (KIST) developed the high-capacity, stretchable lithium-ion battery. The battery was developed by fabricating a structurally stretchable electrode consisting solely of electrode materials and then assembling it with stretchable gel electrolyte and stretchable packaging.

Scientists in the Korea Institute of Science and Technology (KIST) have worked with graphene and carbon nanotubes to develop a working lithium-ion battery that can be stretched by up to 50% without damage to any of the components. According to the scientists, the battery represents a significant step in the development of wearable or body-implantable electronic devices.

Rather than trying to add inherently stretchable materials such as rubber to the battery components, the group focused on creating an accordion-like structure, adding stretchability to materials that are not inherently stretchable. Using graphene and carbon nanotubes, the scientists were able to construct a honeycomb-shaped composite framework, which was then compressed inwardly like an accordion to impart the stretchable properties.

The EU Graphene Flagship has published its graphene application roadmap, showing when the flagship expects different graphene applications to mature and enter the market.

As can be seen in the roadmap above (click here for a larger image), the first applications that are being commercialized now are applications such as composite functional coatings, graphene batteries, low-cost printable electronics (based on graphene inks), photodetectors and biosensors.

Researchers from Italy's ISOF-CNR, University of Naples "Federico II" and Università di Modena e Reggio Emilia have developed new organic n-type FET transistors (OFETs) based on CVD graphene sheets. The researchers say that the new process and materials they used can enable flexible, transparent and short-channel OFETs - which could be used in the future for OLED or OLET (organic light emitting transistor) displays.

To create the new transistors, the researchers used thermally evaporated thin-films of PDIF-CN2 (a perylene diimide derivative) as the the organic semiconductor for the active channel of the transistor with the single-layer CVD graphene (grown at Italy's IIT institute) as the electrode material. The final device architectures have been fabricated via Electron-Beam-Lithography (EBL) and Reactive Ion Etching (RIE).

Researchers from Northwestern University have turned graphene oxide (GO) into a soft, moldable and kneadable "play dough" that can be shaped and reshaped into free-standing, three-dimensional structures.

Called GO dough, this malleable material is said to solve several long-standing problems in the graphene manufacturing industry. Currently graphene oxide is stored as dry solids or powders, which are prone to combustion and explosion, said Jiaxing Huang, who led the study. Or they have to be turned into dilute dispersions, which multiply the material’s mass by hundreds or thousands.

Haydale has announced that it has signed a supply agreement to provide 76kg of its propriety piezoresistive ink to HP1 Technologies (HP1T) over an 18-month period. The value of the Supply Agreement was not disclosed.

HP1T creates bespoke flexible, printed, functionalized nano carbon-based sensor systems that can measure and collect high quality impact and pressure data. This newly signed supply agreement will see Haydale become HP1T's single supplier of functionalized nano carbon inks.

The Graphene Flagship was launched in 2013 with the mission to take graphene and related layered materials from academic laboratories to the market, revolutionize multiple industries and create economic growth and new jobs in Europe. Five years later, the Flagship consortium has reported that it successfully completed the Core1 phase and is progressing towards more applied phases. It is reportedly on its way to achieving its objective of developing the high potential of graphene and related 2D materials to the point of having a dramatic impact on multiple industries.

The Reviewing Panel thoroughly examined the results obtained in this Core1 phase and concluded that for many topics, there has been a clear transformation of the activities, moving from individual research projects to genuine collaboration towards larger goals exactly what a Flagship project should aim for. Nearly all milestones and key performance indicators have been met, often exceeding expectations. There are numerous examples of significant scientific and/or technological achievements, with clear progress beyond the state of the art. The Work package on Photonics and Optoelectronics led by ICREA Prof. at ICFO Frank Koppens was recognized as one of the closest to being brought into industrial exploitation due to its significant potential for both scientific breakthrough and innovation.