Graphene applications: what is graphene used for? - Page 8

Researchers at École Polytechnique Fédérale de Lausanne (EPFL) in Switzerland and National Institute for Materials Science in Japan have combined the electrical properties of graphene with the semiconducting characteristics of indium selenide in a field-effect geometry, to create a device that can efficiently convert heat into electrical voltage at temperatures lower than that of outer space. The innovation could help overcome a significant obstacle to the advancement of quantum computing technologies, which require extremely low temperatures to function optimally.

Device schematic representing a fully encapsulated few-layer InSe channel, with graphene electrodes. Image credit: Nature Nanotechnology

To perform quantum computations, quantum bits (qubits) must be cooled down to temperatures in the millikelvin range (close to -273 Celsius), to slow down atomic motion and minimize noise. However, the electronics used to manage these quantum circuits generate heat, which is difficult to remove at such low temperatures. Most current technologies must therefore separate quantum circuits from their electronic components, causing noise and inefficiencies that hinder the realization of larger quantum systems beyond the lab. Now, researchers in EPFL’s Laboratory of Nanoscale Electronics and Structures (LANES), led by Andras Kis, have fabricated a device that not only operates at extremely low temperatures, but does so with efficiency comparable to current technologies at room temperature.

Graphene Composites USA (GC) has been selected to participate in a research and development program between DEVCOM Soldier Center, Natick MA and UMass Lowell, to develop materials for the next generation of U.S. military footwear.

The program, SWIFT [Supporting Warfighters through Innovative Footwear Technologies], is offered by the HEROES (Harnessing Emerging Research Opportunities to Empower Soldiers) initiative and will see GC extend its patented GC Composite graphene and aerogel technology to develop ultra-lightweight, durable, insulative materials for use in extreme cold weather.

Professors Gil-Ho Lee and Gil Young Cho from Pohang University of Science and Technology (POSTECH) in South Korea have collaborated with Dr. Kenji Watanabe and Dr. Takashi Taniguchi from National Institute for Materials Science (NIMS) in Japan to successfully control the quantum mechanical properties of Andreev bound states in bilayer graphene-based Josephson junctions using gate voltage. 

Superconductors exhibit zero electrical resistance under specific conditions such as extremely low temperatures or high pressures. When a very thin normal conductor is placed between two superconductors, a supercurrent flows through it due to the proximity effect where superconductivity extends into the normal conductor. This device is known as a Josephson junction. Within the normal conductor, new quantum states called Andreev bound states are formed, which are crucial for mediating the supercurrent flow.

Researchers at the University of Antwerp and CIC biomaGUNE have reported a novel method based on graphene, for understanding the role of surface molecules in the formation of nanoparticles. The research provides an advanced characterization tool for the design of nanomaterials.

Gold nanoparticles have been the subject of intense research for several decades due to their interesting applications in fields such as catalysis and medicine. "Surface ligands" are organic molecules typically present on the surface of gold nanoparticles. During synthesis, these surface ligands play an important role in controlling the size and shape of the nanoparticles. For several decades, the CIC biomaGUNE team led by Ikerbasque Research Professor Luis Liz-Marzán has studied the growth mechanisms and properties of these nanoparticles. However, many questions remain about the exact behavior of surface ligands during and after growth. Direct observation of surface ligands and their interface with gold nanoparticles has therefore been a long-standing goal for many scientists in this field.

An India-based EV startup called iVOOMi has launched the S1 Lite, an electric scooter available with two battery options, Graphene and Li-ion. 

The graphene unit offers a range of up to 75 km and takes 7-8 hours to charge fully, while the Li-ion pack provides a range of up to 85 km and can be charged in under 4 hours. Both variants feature a 1.2 kW motor with 1.8 kW peak power and 10.1 Nm of torque.

Researchers from the University of Michigan, SLAC National Accelerator Laboratory, Carnegie Mellon University and Harvard University have shown that three layers of graphene, in a twisted stack, benefit from a similar high conductivity to "magic angle" bilayer graphene but with easier manufacturing—and faster electron transfer. The findings could improve nano electrochemical devices or electrocatalysts to advance energy storage or conversion.

Twisting two sheets of graphene at a 1.1° angle, dubbed the "magic angle," creates a "flat band" structure, meaning the electrons across a range of momentum values all have roughly the same energy. Because of this, there is a huge peak in the density of states, or the available energy levels for electrons to occupy, at the energy level of the flat band which enhances electrical conductivity. Recent work experimentally confirmed these flat bands can be harnessed to increase the charge transfer reactivity of twisted bilayer graphene when paired with an appropriate redox couple—a paired set of chemicals often used in energy storage to shuttle electrons between battery electrodes. Adding an additional layer of graphene to make twisted trilayer graphene yielded a faster electron transfer compared to bilayer graphene, according to the team's recent study, that created an electrochemical activity model.

Malaysian energy company PETRONAS has launched its third graphene-based solution, ProTough+,  under its Advanced Materials portfolio to capture new growth opportunities in line with its Energy Transition Strategy.

ProTough+ is an additive that enhances the strength of composite materials by improving their mechanical properties to achieve component light weighting, which is key in manufacturing and delivery of lower carbon solutions such as hydrogen mobility. Tests conducted on carbon fiber reinforced polymers enhanced with ProTough+ reportedly demonstrated an increase of more than 35% in tensile strength. This allows stronger composite parts to be manufactured with less materials, thus supporting fabrication of products that are lighter and more economical. 

Researchers at Tsinghua University, Zhejiang University and Zhejiang Sanhua Intelligent Controls Co., have designed a graphene-based thermal-switching material for improving the safety of lithium-ion batteries (LIBs) by making sure that they can safely operate at different temperatures and do not explode when overheated.

a) Thermal-switching mechanism of the TSM. b) The self-assembly process through freeze-casting of 2D-flake–microsphere suspensions to form an alternating multilayer scaffold together with polymer infiltration. Image credit: Nature Energy

A general approach to improving the safety of LIBs is using thermal-conducting interlayers, materials designed to even out the temperature between a battery's modules, bringing it to between 15 to 45 °C. To ensure that a high-capacity LIB is safe, these materials should be highly thermally insulating, thus preventing the propagation of heat, while also ensuring that temperature is uniformly distributed in the battery. The research team's newly developed thermal-switching material meets both criteria, and can effectively regulate the temperature in high-capacity batteries. This material rapidly responds to temperature, enabling the safe cycling of batteries in varying operating conditions.

Researchers at Eindhoven University of Technology (TU/e) have designed a soft robotic "hand" made from liquid crystals (LCs) and graphene, that could be used to design future surgical robots. 

One of the issues that need to be addressed before such robots can be used in operating rooms is to figure out how to precisely control and move these deformable robots. Also, many current soft robots contain metals, which means that their use in water-rich environments—like the human body—is rather limited.

Archer Materials, a semiconductor company advancing the quantum technology and medical diagnostics industries, has fabricated one of its Biochip graphene field effect transistor (gFET) designs through a six-inch whole wafer run by its foundry partner in Spain, Graphenea.

Archer had sent the Biochip gFET design to Graphenea for fabrication through a whole wafer run in Dec 20231. The gFETs are designed with structures suitable for liquid multiplexing, with advances in chip design features, including in gating design and materials, to address technological challenges in maintaining graphene device stability from chip-to-chip.