Rice Univ. scientists have found a way to simplify the manufacture of solar cells by using the top electrode as the catalyst that turns plain silicon into valuable black silicon. Black silicon is silicon with a highly textured surface of nanoscale spikes or pores that are smaller than the wavelength of light. The texture allows the efficient collection of light from any angle, at any time of day.
Inspired by the way iridescent bird feathers play with light, scientists have created thin films of material in a wide range of pure colors with hues determined by physical structure rather than pigments. Structural color arises from the interaction of light with materials that have patterns on a minute scale, which bend and reflect light to amplify some wavelengths and dampen others.
Pollutants emitted by factories and car exhausts affect humans who breathe in these harmful gases and also aggravate climate change up in the atmosphere. Being able to detect such emissions is a critically needed measure. New research has developed an efficient way to improve methods for detecting polluting emissions using a sensor at the nanoscale.
Many of us are familiar with electrolytic splitting of water from their school days: If you hold two electrodes into an aqueous electrolyte and apply a sufficient voltage, gas bubbles of hydrogen and oxygen are formed. If this voltage is generated by sunlight in a solar cell, then you could store solar energy by generating hydrogen gas. This is because hydrogen is a versatile medium of storing and using "chemical energy".
Researchers at the Univ. of Georgia have developed an inexpensive way to manufacture extraordinarily thin polymer strings commonly known as nanofibers. These polymers can be made from natural materials like proteins or from human-made substances to make plastic, rubber or fiber, including biodegradable materials.
Think about your favorite toys as a child. Did they light up or make funny noises when you touched them? Maybe they changed shape or texture. In ACS Central Science, researchers report a new material that combines many of these characteristics. Beyond being fun, these materials, called organic “supercooled” liquids, may be useful for optical storage systems and biomedical sensors.
Researchers have demonstrated a new metal matrix composite that is so light that it can float on water. A boat made of such lightweight composites will not sink despite damage to its structure. The new material also promises to improve automotive fuel economy because it combines light weight with heat resistance.
What does space experimentation have in common with liquid cocktails? Both help in understanding what happens when multiple fluids are mixed together and subjected to temperature change—a phenomenon ubiquitous in nature and industrial applications such as oil fluids contained in natural reservoirs. The latest experimental data performed in zero gravity on the International Space Station is now available.
A moth’s eye and lotus leaf were the inspirations for an antireflective water-repelling, or superhydrophobic, glass coating that holds significant potential for solar panels, lenses, detectors, windows, weapons systems and many other products. The discovery is based on a mechanically robust nanostructured layer of porous glass film. The coating can be customized to be superhydrophobic, fog-resistant and antireflective.
An international team of scientists, including Prof. Monica Craciun from the Univ. of Exeter, have pioneered a new technique to embed transparent, flexible graphene electrodes into fibers commonly associated with the textile industry. The discovery could revolutionize the creation of wearable electronic devices, such as clothing containing computers, phones and MP3 players, which are lightweight, durable and easily transportable.
Researchers have demonstrated a new process for the expanded use of lightweight aluminum in cars and trucks at the speed, scale, quality and consistency required by the auto industry. The process reduces production time and costs while yielding strong and lightweight parts, for example delivering a car door that is 62% lighter and 25% cheaper than that produced with today's manufacturing methods.
An international research group led by scientists at NIST has developed a technique for creating nanoscale whispering galleries for electrons in graphene. The development opens the way to building devices that focus and amplify electrons just as lenses focus light and resonators (like the body of a guitar) amplify sound.
For faster, longer-lasting water filters, some scientists are looking to graphene to serve as ultra-thin membranes, filtering out contaminants to quickly purify high volumes of water. Graphene’s unique properties make it a potentially ideal membrane for water filtration or desalination. But there’s been one main drawback to its wider use.
A revolution is coming in flexible electronic technologies as cheaper, more flexible, organic transistors come on the scene to replace expensive, rigid, silicone-based semiconductors, but not enough is known about how bending in these new thin-film electronic devices will affect their performance, say materials scientists at the Univ. of Massachusetts Amherst.
Researchers have developed an inexpensive technique called “microcombing” to align carbon nanotubes, which can be used to create large, pure CNT films that are stronger than any previous such films. The technique also improves the electrical conductivity that makes these films attractive for use in electronic and aerospace applications.
To the list of potential applications of graphene we can now add valleytronics, the coding of data in the wave-like motion of electrons as they speed through a conductor. Lawrence Berkeley National Laboratory researchers have discovered topologically protected 1-D electron conducting channels at the domain walls of bilayer graphene. These conducting channels are “valley polarized".
A team of researchers from Lawrence Livermore National Laboratory and Univ. of California, Davis, have found that covering an implantable neural electrode with nanoporous gold could eliminate the risk of scar tissue forming over the electrode’s surface. The team demonstrated that the nanostructure of nanoporous gold achieves close physical coupling of neurons by maintaining a high neuron-to-astrocyte surface coverage ratio.
One of the fastest-growing areas of solar energy research is with materials called perovskites. These promising light harvesters could revolutionize the solar and electronics industries because they show potential to convert sunlight into electricity more efficiently and less expensively than today’s silicon-based semiconductors.
Who among us hasn't wanted to don a shimmering piece of fabric and instantly disappear from sight? Unfortunately, we non-magical folk are bound by the laws of physics, which have a way of preventing such fantastical escapes. Real-life invisibility cloaks do exist. Researchers have developed a portable invisibility cloak that can be taken into classrooms. It can't hide a human, but it can make small objects disappear from sight.
Most people are naturally adept at reading facial expressions — from smiling and frowning to brow-furrowing and eye-rolling — to tell what others are feeling. Now scientists have developed ultra-sensitive, wearable sensors that can do the same thing.
They may deal in gold, atomic staples and electron volts rather than cement, support beams and kilowatt-hours, but chemists have drafted new nanoscale blueprints for low-energy structures capable of housing pharmaceuticals and oxygen atoms. New research has revealed four atomic arrangements of a gold nanoparticle cluster.
The silver used by Beth Gwinn’s research group at the Univ. of California, Santa Barbara, has value far beyond its worth as a commodity, even though it’s used in very small amounts. The group works with the precious metal to create nanoscale silver clusters with unique fluorescent properties. These properties are important for a variety of sensing applications including biomedical imaging.
Researchers ohave unveiled an important step in the conversion of light into storable energy: They studied the formation of so-called polarons in zinc oxide. The pseudoparticles travel through the photoactive material until they are converted into electrical or chemical energy at an interface.
Taking child's play with building blocks to a whole new level, the nanometer scale, scientists at Brookhaven National Laboratory have constructed 3-D "superlattice" multicomponent nanoparticle arrays where the arrangement of particles is driven by the shape of the tiny building blocks. The method uses linker molecules made of complementary strands of DNA to overcome the blocks' tendency to pack together.
A new type of graphene aerogel will make for better energy storage, sensors, nanoelectronics, catalysis and separations. Lawrence Livermore National Laboratory researchers have made graphene aerogel microlattices with an engineered architecture via a 3D printing technique known as direct ink writing.