The Graphene-Info newsletter

UK-based developer of graphene-based biological sensors, HexagonFab, recently raised £1.9 million to accelerate development of its novel technology for process monitoring in the biopharmaceutical industry.

The company has developed a portable and affordable instrument – HexagonFab Bolt – which can very rapidly generate biopharma data.

A research team at the Center for Molecular Spectroscopy and Dynamics (CMSD) within the Institute for Basic Science (IBS) in Seoul, South Korea, and the Korea University, recently revealed the origin of the wettability of graphene. Wettability is the ability of the interfacial water to maintain contact with a solid surface, and it depends on the material's hydrophobicity. Unlike most materials, the wettability of graphene varies depending on the type of substrate. More specifically, the wettability of the substrate is weakly affected by the presence of a single graphene layer on its surface. Such a peculiar wettability of graphene has been described by the term "wetting transparency" because the wetting properties at the graphene-water interface have little effect on the substrate-water interaction through the thin graphene.

In their new work, the team succeeded at observing the hydrogen-bond structure of water molecules at graphene-water interfaces using a technique called 'vibrational sum-frequency generation spectroscopy (VSFG)'. VSFG is a second-order nonlinear spectroscopy that can be used to selectively analyze molecules with broken centrosymmetry. It is an ideal method for studying the behavior and structures of water molecules at the graphene interface since the water molecules in the bulk liquid are not visible due to their isotropic distribution of molecular orientations.

Researchers at the University of Michigan (U-M) have developed a real-time, 3D motion tracking system developed that combines transparent light detectors with advanced neural network methods. The system could one day replace LiDAR and cameras in autonomous technologies and future applications include automated manufacturing, biomedical imaging and autonomous driving.

The imaging system relies on transparent, highly sensitive graphene photodetectors developed by Zhaohui Zhong, U-M associate professor of electrical and computer engineering, and his group. They’re believed to be the first of their kind.

Researchers from France, South Korea, and Japan have created a graphene-based “beam splitter” for electronic currents. The tunable device’s operation is directly comparable to that of an optical interferometer. The team believes that the technology could enable electron interferometry to be used in nanotechnology and quantum computing.
Quantum Hall valley splitter - schematic representation of the p − n junction. Image from article

An optical interferometer splits a beam of light in two, sending each beam along a different path before recombining the beams at a detector. The measured interference of the beams at the detector can be used to detect tiny differences in the lengths of the two paths. Recently, physicists have become interested in doing a similar thing with currents of electrons in solid-state devices, taking advantage of the fact that electrons behave similarly to waves in the quantum world.

University of Cambridge researchers have designed a lithium-ion battery that can be directly charged in sunlight. This was done in an effort to improve the general process of connecting solar panels to batteries to store energy when the sun is shining.

“The idea is to simplify how solar energy is harvested and stored,” says Michael De Volder, a mechanical engineer at the University of Cambridge who led the work. If the team can improve the efficiency and lifetime of the hybrid device, its cost will likely be lower than combining solar cells and batteries. “For the price of a battery, you get both functionalities,” he says.