Organic solar cells are a compelling thin-film photovoltaic technology in part because of their compatibility with flexible substrates and tunable absorption window. Belgium-based chipmaker imec has set a new conversion efficiency record of 8.4% for this type of cell by developing fullerene-free acceptor materials and a new multilayer semiconductor device structure.
A new study by Berkeley Lab researchers shows that nearly 90% of the electrons generated by a hybrid material designed to store solar energy in hydrogen are being stored in the target hydrogen molecules. Interfacing the semiconductor gallium phosphide with a cobaloxime catalyst provides an inexpensive photocathode for bionic leaves that produce energy-dense fuels from nothing more than sunlight, water and carbon dioxide.
Experts from the Univ. of Buffalo (UB), helped by colleagues from two Chinese universities, have developed an optical "nanocavity" that could help increase the amount of light absorbed by ultrathin semiconductors. The advancement could lead to the creation of more powerful photovoltaic cells and improvements in video cameras and even hydrogen fuel, as the technology could aid the splitting of water using energy from light.
Light-emitting diodes (LEDs) are durable and save energy. Now, researchers have found a way to make LED lamps even more compact while supplying more light than commercially available models. The key to this advance are a new type of transistors made of the semiconductor material gallium nitride.
In physics, there's small, and then there's nullity, as in zero-dimensional. Univ. of Cincinnati researchers have reached this threshold with a special structure, zero-dimensional quantum dots, that may someday lead to better ways of harnessing solar energy, stronger lasers or more sensitive medical diagnostic devices.
JILA physicists used an ultrafast laser and help from German theorists to discover a new semiconductor quasiparticle, a handful of smaller particles that briefly condense into a liquid-like droplet. Quasiparticles are composites of smaller particles that can be created inside solid materials and act together in a predictable way.
Associated with unhappy visits to the dentist, “cavity” means something else in the science of optics. An arrangement of mirrors that allows beams of light to circulate in closed paths, or cavities, help us build laser and optical fibers. Now, a research team pushed the concept further by developing an optical “nanocavity” that boosts the amount of light that ultrathin semiconductors absorb.
An undesired effect in thin film amorphous silicon solar cells has puzzled the scientific community for the last 40 years. This effect, known as light-induced degradation, is responsible for reducing solar cell efficiency over time. Researchers in Germany have recently demonstrated that tiny voids within the silicon network are partly responsible for 10 to 15% efficiency loss as soon as they are used.
European scientists from both academia and industry have begun an ambitious new research project focused on an alternative approach to extend Moore's Law. The research project, coordinated IBM Research in Zurich and called COMPOSE³, is based on the use of new materials to replace today's silicon, and on taking an innovative design approach where transistors are stacked vertically, known as 3-D stacking.
Researchers at Tyndall National Institute in Ireland have produced the first ever atom-by-atom simulation of nanoscale film growth by atomic layer deposition (ALD), a thin-film technology used in the production of silicon chips. The accomplishment required the acquisition of the complete set of hundreds of ALD reactions at the quantum mechanical level.
New research hints that nanodevices in microcircuits can protect themselves from heat generation through the transformation of nanotransistors into quantum states. The finding, demonstrated in nanoscale semiconductors devices, could boost computing power without large-scale changes to electronics.
Researchers have tried a variety of methods to develop detectors that are responsive to a broad range of infrared light, but these methods have all faced limitations. Now, a new system developed by researchers at five institutions could eliminate many of those limitations. The new system works at room temperature and provides a broad infrared response.
The goal of fabricating fixed-size one-dimensional silica structures and being able to precisely control the diameter during growth has long eluded scientists. Now, Oak Ridge National Laboratory researchers Panos Datskos and Jaswinder Sharma have demonstrated what they describe as the addressable local control of diameter of each segment of the silica rod.
There are examples of art imitating nature all around us, from Monet to Chihuly, but when physicist Latika Menon peered under the electron microscope last fall, she discovered the exact opposite in gallium nitride nanowires that bore an uncanny resemblance to artistic pots found in her native India. Menon has begun to control these shapes, which will make the nanowires significantly more promising for use in advanced devices.
By applying pressure to a semiconductor, researchers have been able to transform a semiconductor into a “topological insulator” (TI), an intriguing state of matter in which a material’s interior is insulating but its surfaces or edges are conducting with unique electrical properties. This is the first time that researchers have used pressure to gradually “tune” a material into the TI state.
Transistors, the workhorses of the electronics world, are plagued by leakage current. This results in unnecessary energy losses, which is why smartphones and laptops, for example, have to be recharged so often. Researchers have recently shown that this leakage current can be radically reduced by “squeezing” the transistor with a piezoelectric material. Using this approach, they have surpassed the theoretical limit for leakage current.
Spontaneous bursts of light from a solid block illuminate the unusual way interacting quantum particles behave when they are driven far from equilibrium. The discovery by Rice Univ. scientists of a way to trigger these flashes may lead to new telecommunications equipment and other devices that transmit signals at picosecond speeds.
New work by researchers at Univ. of California, Berkeley could soon transform the building blocks of modern electronics by making nanomagnetic switches a viable replacement for the conventional transistors found in all computers.
Stanford Univ. researchers have developed an inexpensive device that uses light to split water into oxygen and clean-burning hydrogen. The goal is to supplement solar cells with hydrogen-powered fuel cells that can generate electricity when the sun isn't shining or demand is high.
When you squeeze atoms, you don’t get atom juice. You get magnets. According to a new theory by Rice Univ. scientists, imperfections in certain 2-D materials create the conditions by which nanoscale magnetic fields arise. Calculations by the laboratory of Rice theoretical physicist Boris Yakobson show these imperfections, called grain boundaries, in 2-D semiconducting materials known as dichalcogenides can be magnetic.
Semiconductors, the foundation of modern electronics used in flatscreen televisions and fighter jets, could become even more versatile as researchers make headway on a novel, inexpensive way to turn them into thin films. Their report on a new liquid that can quickly dissolve nine types of key semiconductors appears in the Journal of the American Chemical Society.
Researchers from the Univ. of Pennsylvania and Drexel Univ. have experimentally demonstrated a new method for solar cell construction which may ultimately make them less expensive, easier to manufacture and more efficient at harvesting energy from the sun. The breakthrough, which is the result of five years of focused research, relies on specifically designed perovskite crystals that deliver a “bulk” photovoltaic effect.
When an earthquake and tsunami struck Japan’s Fukushima nuclear power plant in 2011, crews sprayed cooling seawater on the reactors, but to no avail. One possible reason: Droplets can’t land on surfaces that hot and instantly begin to evaporate, forming a thin layer of vapor and then bouncing along it. Now, MIT researchers have come up with a way to cool hot surfaces more effectively by keeping droplets from bouncing.
Researchers in Basque country in Spain have developed and patented a new source of light emitter based on boron nitride nanotubes. Suitable for developing high-efficiency optoelectronic devices, the structural defects in the nanotubes help make it extremely efficient in ultraviolet light emission.
Amit Goyal and his team of research scientists are using copper oxide to redesign the face of solar power. The once-dismissed solar semiconductor, one of the first discovered, is the basis of ongoing research at Oak Ridge National Laboratory, where scientists are creating cheaper and safer alternatives for solar conducting technology.