Electronics - Page 22

Scientists from UCLA’s California NanoSystems Institute have designed an effective way to use graphene in order to place molecules specific patterns within tiny nanoelectronic devices, which could be useful in creating sensors that are even small enough to record brain signals.

This is done by using a sheet of graphene with minuscule holes in it that is then placed on a gold substrate. The holes allow molecules to attach to the gold exactly where the scientists want them, creating patterns that control the physical shape and electronic properties of devices that are 10,000 times smaller than the width of a human hair.

An international team of researchers at Tohoku University in Japan has demonstrated the ability to interconnect graphene nanoribbons (GNRs) end to end, using molecular assembly that forms elbow structures (interconnection points). This development may provide the key to unlocking GNRs’ potential in high-performance and low-power-consumption electronics.

GNRs are interesting as their width determines their electronic properties; Narrow ones are semiconductors, while wider ones act as conductors, which basically  provides a simple way to engineer a band gap into graphene for use in electronics.

The OLED Association, a trade group that promotes OLED technologies, published an interesting article in which they give predictions for the OLED market. The Association sees Samsung returning to the OLED TV market in 2017, and those upcoming OLED TVs will use several new technologies - including graphene-based transparent electrodes.

Last month we reported that researchers at Korea's ETRI developed transparent graphene-based electrodes for OLED panels. The researchers say that these new electrodes improve the transparency and "image quality" of OLEDs by 40 to 60 percent, compared to current silver-based electrodes. The researchers aim to continue the research and improve the performance of their electrodes.

Researchers have reported a graphene-based material with special electric properties, which might enable the production of better energy storage devices. The material follows the predictions of physicists from the University of Luxembourg that three years ago had theoretically predicted the unusual characteristics of a particular composite material. These calculations could now finally be confirmed by experiment in cooperation with the Centre de Recherche Paul Pascal in Bordeaux, France, and resulted in the discovery of a so-called high-k-material, which might enable the production of better energy storage devices the basis for smaller, faster and more efficient electronics.

Earlier calculations indicated disappointing results - certain compound materials made of polymers and flaky graphene, as opposed to those made of polymers and carbon nanotubes, did not increase the conductivity of the material to the degree that was generally expected until then. These were bad news that clouded graphene's perceived future in creating composites with increased conductivity. 

Researchers at the University of Manchester have demonstrated how graphene's conductivity and flexibility will prove crucial to wearable electronic applications, opening the door to battery-free healthcare and fitness monitoring, phones, internet-ready devices and chargers to be incorporated into clothing and ‘smart skin’ applications (printed graphene-based sensors integrated with other 2D materials and put onto a patient’s skin to monitor temperature, strain and moisture levels).

The researchers printed graphene to create transmission lines and antennae and experimented with these in communication devices. They used a mannequin to which they attached graphene-enabled antennae on each arm, and found that the devices were able to communicate with each other, effectively creating an on-body communications system. These results show that such graphene-based components have the required quality and functionality for wireless wearable devices.

Researchers at Aalto University in Finland have successfully realized extremely thin metallic graphene nanoribbons (GNRs) - only 5 carbon atoms wide. The team demonstrated fabrication of the GNRs and measured their electronic structure, with results that suggest that these extremely narrow ribbons could be used as metallic interconnects in future microprocessors.

GNRs have been suggested as ideal wires for use in future nanoelectronics: when the size of the wire is reduced to the atomic scale, graphene is expected to outperform copper in terms of conductance and resistance to electromigration - the typical breakdown mechanism in thin metallic wires. However, previously demonstrated graphene nanoribbons have been semiconducting, which hampers their use as interconnects. Now, the researchers have shown that certain atomically precise graphene nanoribbon widths are nearly metallic, in accordance with earlier predictions based on theoretical calculations.

Carbon Sciences has been working on developing graphene-based devices for cloud computing. Now, the company announced that it has signed an agreement with the University of California, Santa Barbara (UCSB) to fund the research and development of a new graphene-based optical modulator, a critical fiber optics component needed to enable ultrafast communication in data centers for Cloud computing.

In order for data to be transmitted through a fiber optic cable, light from a laser beam must be modulated. The amount of data that can be encoded and transmitted depends on the speed of the light beam modulation. Since changing the conductivity of graphene also changes its optical properties, light passing through it will also be changed accordingly to encode digital data. This, along with graphene's impressive features are to enable the development of an ultrafast, low cost, and low power, graphene-based optical modulator.

Researchers at the University of Maryland, along with collaborators from the National Institute of Standards and Technology (NIST), have developed a theoretical model that demonstrates how to shape and stretch graphene to create a powerful, adjustable and sustainable magnetic force. This discovery could also be a major step in understanding how electrons move in extremely high magnetic fields.

Graphene's electrons react to stretching or straining by behaving as if they are in a strong magnetic field. This so-called pseudomagnetic effect could open up new possibilities in graphene electronics, but so far, researchers have only been able to induce limited pseudofields that are far from to realizing in practice. However, Maryland researchers may have explained how to shape a graphene ribbon so that simply pulling its two ends produces a uniform pseudomagnetic field.The team is confident that they will soon be able to transition their theoretical model to a design reality.

Rice University researchers have configured their previous invention of Laser Induced Graphene (LIG) into flexible, solid-state microsupercapacitors that rival current leading ones for energy storage and delivery.

The LIG microsupercapacitors reportedly charge 50 times faster than batteries, discharge more slowly than traditional capacitors and match commercial supercapacitors for both the amount of energy stored and power delivered. The devices are made by burning electrode patterns with a commercial laser into plastic sheets in room-temperature air, eliminating the complex fabrication conditions that have limited the widespread application of microsupercapacitors.

Graphene 3D Lab has announced Graphene Flex Foam, a new commercial product that will be available through Graphene Laboratories’ e-commerce site, Graphene Supermarket. The new product is described as a Multilayer Freestanding Flexible Graphene Foam, that brings together a conductive elastomer composite with ultra-light graphene foam.

The foam, a highly conductive 3D chemical vapor deposition (CVD), together with the composite, brings together the best of several worlds of graphene usage. As a flexible foam, the material is both lightweight and reconfigurable, adding to ease of use and handling, with a porous structure. The Graphene Flex Foam could be used in conjunction with other graphene-related materialssuch as Graphene 3D Lab’s filament offeringsin the creation of electronics and other conductive products.