Researchers design method that makes graphene nanoribbons easier to produce

Russian researchers have proposed a new method for synthesizing high-quality graphene nanoribbons. The team's approach to chemical vapor deposition offers a higher yield at a lower cost, compared with the currently used nanoribbon self-assembly on noble metal substrates.

Two nanoribbon edge configurations imageTwo nanoribbon edge configurations. The pink network of carbon atoms is a ribbon with zigzag (Z) edges, and the yellow one has so-called armchair (A) edges. Image credit MIPT

Unlike silicon, graphene does not have the ability to switch between a conductive and a nonconductive state. This defining characteristic of semiconductors is crucial for creating transistors, which are the basis for all of electronics. However, once you cut graphene into narrow ribbons, they gain semiconducting properties, provided that the edges have the right geometry and there are no structural defects. Such nanoribbons have already been used in experimental transistors with reasonably good characteristics, and the material’s elasticity means the devices can be made flexible. While it is technologically challenging to integrate 2D materials with 3D electronics, there are no fundamental reasons why nanoribbons could not replace silicon.

Researchers develop monolayer graphene-based reversible self-folding structures

A team of scientists at Johns Hopkins University in the U.S. has designed a mass-production strategy to create monolayer graphene-based reversible self-folding structures. The material may find potential uses in microfluidics and micromechanical systems.

 Share  Email  Home Nanotechnology Nanophysics Home Nanotechnology Nanomaterials JANUARY 11, 2021 FEATURE  Self‐folding 3-D photosensitive graphene architectures imageMechanism and versatility of self‐folding SU8 films. Image from article

As proof of concept, the team achieved complex and functional devices in the form of rings, polyhedra, flowers and origami birds. They then integrated gold electrodes to the constructs to improve their detection sensitivity. The experiments suggest a comprehensive framework to rationally design and fabricate scalable and complex, 3D, self-folding optical and electronic devices by folding 2D monolayer graphene.

Researchers design a novel method for modifying the structure and properties of graphene

An international research team from China, France, Canada, Denmark and the UK has demonstrated a novel process to modify the structure and properties of graphene. This chemical reaction, known as photocycloaddition, modifies the bonds between atoms using ultraviolet light.

A new method for the functionalization of graphene image

The researchers demonstrated a spatially selective photocycloaddition reaction of a two-dimensional molecular network with defect-free basal plane of single-layer graphene. The cycloaddition is triggered by ultraviolet irradiation in ultrahigh vacuum, requiring no aid of the graphene Moiré pattern. This work could open the door to designing and engineering graphene-based optoelectronic and microelectronic devices.

International team develops novel method to modify the structure and properties of graphene

An international research team, that included researchers from the Harbin Institute of Technology in China, INRS in France and more, has demonstrated a novel process to modify the structure and properties of graphene. This process relied on a chemical reaction known as photocycloaddition, that modifies the bonds between atoms using ultraviolet (UV) light.

Photocycloaddition of the BCM layer with graphene image

"No other material has properties similar to graphene, yet unlike semiconductors used in electronics, it lacks a band gap. In electronics, this gap is a space in which there are no energy levels that can be occupied by electrons. Yet it is essential for interacting with light," explains Professor Federico Rosei of INRS's Énergie Matériaux Télécommunications Research Centre.

Researchers design a lightweight and highly efficient graphene heat pipe

Researchers at Sweden-based Chalmers University of Technology, in collaboration with researchers in China and Italy, have found that graphene-based heat pipes can help solve the problems of cooling electronics and power systems used in avionics, data centers, and other power electronics.

Cooling electronics efficiently with graphene-enhanced heat pipes imageA) Image of a real GHP; B) schematic designing of the GHP; C) working principle of the GHP

Electronics and data centers need to be efficiently cooled and rid of excess heat in order to function properly. Currently, heat pipes are usually made of copper, aluminum or their alloys. Due to the relatively high density and limited heat transmission capacity of these materials, heat pipes are facing severe challenges in future power devices and data centers.