Following up on previous theoretical predictions, researchers now have demonstrated two high-yield methods for fabricating antimonenes - wide-band-gap semiconductors that under strain become direct band-gap semiconductors. 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. The new approach is generic for various transparent conducting oxides as well as other oxide nanocrystal inks.
Oxygen evolution reaction (OER) is the core process - but also the bottleneck - in many energy devices such as metal-air batteries and water-splitting techniques, calling for new insights in rational design of OER electrocatalysts. The perovskite family exhibits superb OER reactivity, but its poor conductivity remains a big problem, not to mention that the morphology of perovskite oxides is hard to control. In situ hybridization of perovskite oxides with conductive frameworks is an efficient strategy to solve these problems, as researchers report in new work.
Jellyfish can change from a transparent state to an opaque state when disturbed. Tactile stimulation can instantaneously evoke the contraction of radial muscles in the margin of a nectosac, resulting in a crumpled morphology with inward folds. Due to the wrinkles/folding that form, light will be scattered instead of travelling directly through the skin, resulting in a more opaque appearance. Inspired by marine life, a variety of these mechanochromic devices are created by researchers. These devices are able to undergo change from transparency to opaqueness, as well as a changes in color and pattern upon simply stretching and releasing the substrate.
Graphene, one of the most exciting two-dimensional materials, has shown extraordinary optical properties due to strong surface plasmon polaritons supported by graphene nanostructure. Graphene metasurfaces show plasmonic resonance bands that can be tuned from mid-infrared to terahertz regime. These plasmonic devices can be used for biosensing, spectroscopy, light modulation and communication applications. Researchers now demonstrate for the first time an effective method to pattern large area graphene into moire metasurfaces with gradient nanostructures having multiband resonance peaks in mid infrared range.
Whether it is possible to achieve high formability in quasicrystals and how quasicrystals are plastically deformed at room temperature have been long-standing questions since their discovery. In new work, an international group of researchers has found that a typically brittle quasicrystal exhibits superior ductility (ductility is a solid material's ability to deform under stress without fracture) at the sub-micrometer scales and at room temperature. Furthermore, their experiments indicate that 'dislocation glide' could be the dominating deformation mechanism for quasicrystals under high-stress and low temperature conditions, which has been not poorly understood before.
The entry of nanotechnology into manufacturing has been compared to the advent of earlier technologies that have profoundly affected modern societies, such as plastics, semiconductors, and even electricity. Applications of nanotechnology promise transformative improvements in materials performance and longevity for electronics, medicine, energy, construction, machine tools, agriculture, transportation, clothing, and other areas. However, the path to greater benefits from nanomanufactured goods and services is not yet clear. This review takes silicon integrated circuit manufacturing as a baseline in order to consider the factors involved in matching processes with products, examining the characteristics and potential of top-down and bottom-up processes, and their combination.
Over the past few decades, the development of electron microscopy has gone hand in hand with techniques for atomically precise fabrication of 3D structures based on electron and ion beams. A recent review article illustrates the use of focused electron and ion beams (e-beams and i-beams) to induce highly localized chemical reactions at solid-vapor and solid-liquid interfaces, amorphous to crystalline phase transformations with atomic layer precision, and the motion of specific single dopant atoms within crystal lattices, thus laying the foundation for atomically precise directed assembly of materials and devices.
High-temperature heaters, such as furnaces, are widely used in chemical reactions, materials synthesis and device processing. The limitations of these heating devices often are their bulky size, weight, low maximum heating temperatures and slow ramp rates. To overcome these limitations, and to provide a heating element with a high temperature range to the target object in a micro- and nanoscale environment, researchers have developed a 3D-printable high-temperature, high-rate heater that can be applied to a wide range of nanomanufacturing when precise temperature control in time, placement, and the ramping rate is important.