Modern-day electronics or communication technology would not exist without electron microscopy, and the same can be said for many other types of technology. Beyond imaging, the focused beam of electrons is also used for analysis of the chemical composition, the crystal structure, and many other useful things. In new work, researchers have proposed to use graphene as a two-dimensional vacuum chamber, and build a two-dimensional electron microscope, where the electrons fly from the electron gun to the target without ever leaving the graphene sheet.
Steam is important for desalination, hygiene systems, and sterilization; and in remote areas where the sun is the only source of energy, being able to generate steam with solar energy could be very useful. Researchers now have found that the mushroom structure can surprisingly benefit solar steam generation. The stipe of the mushroom can serve as efficient water supply path, meanwhile, due to the extreme small ratio of the areas of fibrous stipe and black pileus, only little heat (useless heat loss) conducted into water.
Researchers have demonstrated a fully integrated and packaged wireless sensor for environmental monitoring applications. The disposable sensor was developed using low-cost additive manufacturing technologies; namely, inkjet printing and 3D printing. This is a demonstration of 3D-printed fully-integrated System-on-Package (SoP) employing inkjet-printed sensors. This work could pave the way for low-cost disposable fully integrated wireless sensor nodes.
Research groups around the world are taking big strides towards developing ultrathin and flexible sensor devices that could be attached to the skin, or even organs, and monitor vital body functions. However, the adhesion to skin of many of these sensor patches is weak. A new milestone study on skin adhesives for wearable devices is about to change that. It demonstrates that it is possible to strongly and non-invasively attach soft wearable sensors and other devices to dry or wet skin.
In new work, a research team has developed a general synthesis strategy by employing graphene oxide as a sacrificial template to prepare various 2D holey transition metal oxide (TMO) nanosheets, including mixed metal oxides and simple metal oxides. This approach is universal for the synthesis of various 2D holey TMO nanosheets including mixed transition-metal oxides and simple oxides. This unique holey structure can minimize the restacking of 2D nanosheets and provide more active sites for alkali-ion storage.
Researchers have utilized a rotating triboelectric nanogenerator (R-TENG) to enhance a polyimide nanofiber air filter for particulate matter (PM) removal. The nanofiber filter exhibits high removal efficiency for the PM particles with diameter larger than 0.5 microns. When working with the R-TENG, the removal efficiency of the filter is enhanced, especially in the region with the diameter of the particles in the PM smaller than 100 nm. This work may propose an approach of air cleaning and haze management by introducing TENGs to the filters.
Inspired by octopus arms, researchers demonstrate an uncomplicated and scalable templating technology for fabricating nanosuckers on PDMS substrates, using a scalable spin-coating technology. As the nanosuckers are pressed against a substrate, the flexible nanosuckers confirm to the substrate and deform by releasing the internal air between nanosuckers and the substrate, forming a seal and generating an adhesion force. The nanosucker adhesion is maintained over multiple contact cycles on both wet and dry surfaces.
The development of porous one-dimensional (1D) nanomaterials with designed properties and architectures has led to significant advances in electrochemical energy storage. A recent review article highlights the state-of-the-art on porous 1D nanostructures, from methodologies for rational and controllable synthesis (electrospinning, liquid phase method, template-assisted method, chemical deposition method, and chemical etching) to their successful application in different types of energy storage devices.