Researchers have identified novel 2D wide-band-gap semiconductors with high stabilities, namely monolayer arsenene and antimonene. These materials are indirect wide-band-gap semiconductors, and under strain, they become direct band-gap semiconductors. For arsenene and antimonene, such dramatic transitions of electronic properties could open a new door for nanoscale transistors with high on/off ratio, blue/UV optoelectronic devices, and nanomechanical sensors based on new ultrathin semiconductors.
A widely discussed method for the patterning of graphene is the channelling of graphene by metal nanoparticles in oxidizing or reducing environments. Researchers have now performed in-situ transmission electron microscopy experiments of silver nanoparticles channeling on graphene and discover that the interactions in the one-dimensional particle-graphene contact line are sufficiently strong so as to dictate the three-dimensional shape of the nanoparticles.
The surface force balance (SFB) provides measurements of surface and colloidal forces in liquids such as electrostatic surface forces, van der Waals forces, and solvation forces. Until now, the SFB required mica sheets as the substrate for measurements. This was the only material available in an atomically smooth state over centimeter-scale areas as well as being optically transparent as required for the optical interferometry. By replacing the mica sheets with graphene, electrically conducting and atomically smooth surfaces for the measurement of surface forces have now been created.
Graphene's properties appear to have almost limitless application potential, ranging from composite materials for the aerospace industry, next-generation batteries and supercapacitors, flexible displays and optical electronics and biosensors for applications in healthcare and medical devices. So why hasn't graphene, with the potential to vastly outperform the majority of currently available materials, been integrated into everything from wristwatches to ocean liners?
The successful implementation of graphene-based devices invariably requires the precise patterning of graphene sheets at both the micrometer and nanometer scale. Finding the ideal technique to achieve the desired graphene patterning remains a major challenge. Researchers have now demonstrated 3D printed nanostructures composed entirely of graphene using a new 3D printing technique. The method exploits a size-controllable liquid meniscus to fabricate 3D reduced graphene oxide nanowires.
Studying the complex wiring of neural circuits and identifying the details of how individual neural circuits operate in epilepsy and other neurological disorders requires real-time observation of their locations, firing patterns, and other factors. These observations depend on high-resolution optical imaging and electrophysiological recording. Researchers have now developed a completely transparent graphene microelectrode that allows for simultaneous optical imaging and electrophysiological recordings of neural circuits.
Researchers are confident that graphene may outperform existing transparent conductive materials. However, monolayer graphene might not be sufficient for fabricating a highly conductive electrode. The dilemma is that the transmittance of graphene film decreases as the number of layers increases. It therefore is of great importance to have a fast and reliable method to determine the number of layers in the fabrication and measurement of multilayer graphene.
Molybdenum disulfide's (MoS2) semiconducting ability, strong light-matter interaction and similarity to graphene makes it of interest to scientists as a viable alternative in the manufacture of electronics, particularly photoelectronics. In pushing towards practical optical applications of two-dimensional (2D) MoS2, an essential gap on understanding the nonlinear optical response of 2D MoS2 and how it interacts with light, must be filled.