Graphene on hBN transistor displays remarkable cooling properties

Researchers from the Pierre Aigrain Laboratory in the ENS Physics department in Paris, France, have discovered a new cooling mechanism for electronic components made of graphene deposited on boron nitride. The efficiency of this mechanism reportedly allowed the team to reach electric intensities at the intrinsic limit of the laws of conduction.

ENS graphene transistor results imageCurrent-voltage (left) and temperature-voltage (right) characteristics of a graphene on boron nitride transistor. The transistor effect is visible by modulation of the current as a function of the gate voltage in the Zener-Klein tunnel transport regime.

Heat dissipation is vital in order to prevent deterioration or destruction of electronic components. The laws of physics dictate that increasing the density of components on a chipset implies increasing dissipation and thus heat. Nowadays, with the advances in 2D material devices, this question becomes particularly critical since components are required to be one atom thick. By producing a graphene-based transistor deposited on a boron nitride substrate, the team demonstrated a new cooling mechanism 10 times more efficient than basic heat diffusion. This new mechanism, which exploits the two-dimensional nature of the materials opens a "thermal bridge" between the graphene sheet and the substrate.

Graphene-based cell-sized robots are on their way!

Researchers from Cornell have developed tiny graphene-enhanced robot exoskeletons that can rapidly change shape upon sensing chemical or thermal changes in its environment. And, they claim, these microscale machines – equipped with electronic, photonic and chemical payloads – could become a powerful platform for robotics at the size scale of biological microorganisms.

“We are trying to build what you might call an ‘exoskeleton’ for electronics,” said the team. “Right now, you can make little computer chips that do a lot of information-processing … but they don’t know how to move or cause something to bend”.

New method could produce industrial scale graphene-enhanced e-textiles

Scientists at The University of Manchester have reported the development of a simple and cost-effective method to manufacture graphene-based wearable electronic textiles on an industrial scale. The new method could allow graphene e-textiles to be manufactured at commercial production rates of 150 meters per minute, the team said. “Our simple and cost-effective way of producing multi-functional graphene textiles could easily be scaled up for many real-life applications, such as sportswear, military gear, and medical clothing,” said the researchers.

Manchetser develops new method for GO e-textiles image

The team reversed the previous process of coating textiles with graphene-based materials; Traditionally, the textiles are first coated with graphene oxide, which is then converted into its functional form of reduced graphene oxide. Instead, the researchers first reduced the graphene oxide in solution, and then coated the textiles with the reduced form.

A new printing method produces flexible graphene micro-supercapacitors with a planar architecture

A team of researchers at the University of Minnesota and Northwestern University, USA, have developed a printing method to produce flexible graphene micro-supercapacitors with a planar architecture suitable for integration in portable electronic devices.

Graphene MSCs with planar architecture process image

The new process, referred to as ‘self-aligned capillarity-assisted lithography for electronics’ (SCALE), begins with the creation of a polymer template, generated by stamping a UV-curable polymer with a PDMS mold. High-resolution inkjet printing is then used to deposit a graphene ink into the template, which is annealed using a xenon lamp to form the electrodes. In the final step, a polymer gel electrolyte is printed onto the template over the electrodes to complete the configuration.

Cambridge University inkjet prints graphene-hBN FETs on textiles

Researchers from Cambridge University have demonstrated how graphene and other related 2D materials (namely hBN) can be directly printed onto textiles to create fully inkjet-printed dielectrically gated field effect transistors (FETs) with solution processed 2D materials.

Cambridge team prints graphene-hbn inks on textiles image

According to the team, these devices are washable, flexible, cheap, safe, comfortable to wear and environmentally-friendly, essential requirements for applications in wearable electronics. The team also demonstrated the first reprogrammable memories, inverters and logic gates with solution processed 2D materials by coupling these FETs together to create integrated circuits, the most fundamental components of a modern-day computer.

XFNANO: Graphene and graphene-like materials since 2009XFNANO: Graphene and graphene-like materials since 2009