Researchers track the path of calcium atoms added to graphene

Researchers from Australia's Monash University, U.S Naval Research Laboratory, University of Maryland and IMDEA Nanociencia in Spain have confirmed what actually happens to calcium atoms that are added to graphene in order to create a superconductor: surprisingly, the calcium goes underneath both the upper graphene sheet and a lower ‘buffer’ sheet, ‘floating’ the graphene on a bed of calcium atoms.

Injecting calcium into graphene creates a superconductor, but where does the calcium actually end up image

Superconducting calcium-injected graphene holds great promise for energy-efficient electronics and transparent electronics.

Researchers use graphene to create detachable flexible microLED devices

University of Texas at Dallas researchers and their international colleagues have developed a graphene-based method to create micro LEDs that can be folded, twisted, cut and stuck to different surfaces. The research could help pave the way for the next generation of flexible, wearable technology.

Graphene helps create flexible and detachable micro LEDs image(A) Photograph of EL light emission from MR LED in a bent form. (B) Cross-sectional schematic of MR heterostructures grown on graphene-coated c-Al2O3 wafer. Image from Science Advances

Used in various applications like signage and automotive lights, LEDs are ubiquitous because they are lightweight, thin, energy efficient and visible in different types of lighting. Micro LEDs, which can be as small as 2 micrometers and bundled to be any size, provide higher resolution than LEDs. Their size makes them a good fit for small devices such as smart watches, but they can be bundled to work in flat-screen TVs and other larger displays. LEDs of all sizes, however, are brittle and typically can only be used on flat surfaces. The researchers’ new micro LEDs aim to enable bendable, wearable electronics.

New graphene nanoribbons could enable smaller electronic devices

A new collaborative study has reported a 17-carbon wide graphene nanoribbon and found that it has the tiniest bandgap observed so far among familiar graphene nanoribbons prepared through a bottom-up approach.

17-carbon wide graphene nanoribbons to pave the way for new GNR-based electronic devices image(a) Bottom-up synthesis scheme of 17-AGNR on Au(111), (b) high-resolution STM image, and (c) nc-AFM image of 17-AGNR. Image Credit: Junichi Yamaguchi, Yasunobu Sugimoto, Shintaro Sato, Hiroko Yamada.

The study is part of a project of CREST, JST Japan including Nara Institute of Science and Technology (NAIST), the University of Tokyo, Fujitsu Laboratories and Fujitsu.

Researchers design a novel method for construction of van der Waals heterostructures using a dual-function polymeric film

A team of researchers has found a novel method for the construction of high-quality van der Waals (vdW) heterostructures, that are vital for many scientific studies and technological applications of layered materials. The work is a collaboration between the laboratory of Davood Shahrjerdi, a professor of Electrical and Computer Engineering at the NYU Tandon School of Engineering and a faculty member of NYU WIRELESS; a group led by Javad Shabani at the Center for Quantum Phenomena, New York University; and Kenji Watanabe and Takashi Taniguchi of National Institute for Materials Science, Japan.

Fabrication of vdW heterostructures image

A crucial step for building vdW graphene heterostructures is the production of large monolayer graphene flakes on a substrate, a process called mechanical exfoliation. The process then involves transferring the graphene flakes onto a target location for the assembly of the vdW heterostructure. An optimal substrate would therefore make it possible to efficiently and consistently exfoliate large flakes of monolayer graphene and subsequently release them on-demand for constructing a vdW heterostructure.

Stretchable Li-ion battery enhanced with graphene and CNTs to benefit wearable electronics

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.

KIST team develops stretchable Li-ion battery with graphene and CNTs image

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.