Showing 20 articles starting at article 401

< Previous 20 articles        Next 20 articles >

Categories: Energy: Alternative Fuels, Space: Cosmology

Return to the site home page

     (via sciencedaily.com)     Original source 

Photovoltaics, the conversion of light to electricity, is a key technology for sustainable energy. Since the days of Max Planck and Albert Einstein, we know that light as well as electricity are quantized, meaning they come in tiny packets called photons and electrons. In a solar cell, the energy of a single photon is transferred to a single electron of the material, but no more than one. Only a few molecular materials like pentacene are an exception, where one photon is converted to two electrons instead. This excitation doubling, which is called exciton fission, could be extremely useful for high-efficiency photovoltaics, specifically to upgrade the dominant technology based on silicon. Researchers have now deciphered the first step of this process by recording an ultrafast movie of the photon-to-electricity conversion process, resolving a decades-old debate about the mechanism of the process.

     (via sciencedaily.com)     Original source 

Perovskite solar cells (PVSCs) are a promising alternative to traditional silicon-based solar cells because of their high power-conversion efficiency and low cost. However, one of the major challenges in their development has been achieving long-term stability. Recently, a research team made a breakthrough by developing an innovative multifunctional and non-volatile additive which can improve the efficiency and stability of perovskite solar cells by modulating perovskite film growth. This simple and effective strategy has great potential for facilitating the commercialization of PVSCs.

     (via sciencedaily.com)     Original source 

A 'beautiful effect' predicted by quantum electrodynamics (QED) can explain the puzzling first observations of polarized X-rays emitted by a magnetar -- a neutron star featuring a powerful magnetic field, according to an astrophysicist.

     (via sciencedaily.com)     Original source 

Using ESO's Very Large Telescope (VLT), researchers have found for the first time the fingerprints left by the explosion of the first stars in the Universe. They detected three distant gas clouds whose chemical composition matches what we expect from the first stellar explosions. These findings bring us one step closer to understanding the nature of the first stars that formed after the Big Bang.

     (via sciencedaily.com)     Original source 

A new study looked at a known binary star (two stars orbiting around a mutual center of gravity), analyzing starlight obtained from a range of ground- and space-based telescopes. The researchers found that the stars, located in a neighboring dwarf galaxy called the Small Magellanic Cloud, are in partial contact and swapping material with each other, with one star currently 'feeding' off the other. They orbit each other every three days and are the most massive touching stars (known as contact binaries) yet observed.

     (via sciencedaily.com)     Original source 

Researchers have developed a chemical process that can disassemble the epoxy composite of wind turbine blades and simultaneously extract intact glass fibers as well as one of the epoxy resin's original building blocks in a high quality. The recovered materials could potentially be used in the production of new blades.

     (via sciencedaily.com)     Original source 

Scientists have unlocked one of the biggest mysteries of quasars -- the brightest, most powerful objects in the Universe -- by discovering that they are ignited by galaxies colliding.

     (via sciencedaily.com)     Original source 

Every giant was once a baby, though you may never have seen them at that stage of their development. NASA's James Webb Space Telescope has begun to shed light on formative years in the history of the universe that have thus far been beyond reach: the formation and assembly of galaxies. For the first time, a protocluster of seven galaxies has been confirmed at a distance that astronomers refer to as redshift 7.9, or a mere 650 million years after the big bang. Based on the data collected, astronomers calculated the nascent cluster's future development, finding that it will likely grow in size and mass to resemble the Coma Cluster, a monster of the modern universe.

     (via sciencedaily.com)     Original source 

Organic solar cells have a photoactive layer that is made from polymers and small molecules. The cells are very thin, can be flexible, and are easy to make. However, the efficiency of these cells is still much below that of conventional silicon-based ones. Applied physicists have now fabricated an organic solar cell with an efficiency of over 17 percent, which is in the top range for this type of material. It has the advantage of using an unusual device structure that is produced using a scalable technique.

     (via sciencedaily.com)     Original source 

Why does it feel so difficult to shout upwind? The sensation is common enough to have found its way into an idiom about not being understood. Researchers wanted a scientific explanation for the phenomenon -- and there wasn't been one. They have now shown that our common sense understanding of this situation is wrong. It isn't harder to shout into the wind; it's just harder to hear yourself.

     (via sciencedaily.com)     Original source 

Researchers developed a proof of concept for a superconducting highway that could transport vehicles and electricity, cooling the necessary superconductors with a pipeline of liquid hydrogen. Most magnetic levitation designs feature the superconductor inside the vehicle, which is suspended above a magnetic track. The authors decided to flip that arrangement upside down, putting the superconductor on the ground and giving each vehicle a magnet. The result is a system with multiple uses, placing it within the realm of affordability.

     (via sciencedaily.com)     Original source 

A study using data from telescopes on Earth and in the sky resolves a problem plaguing astronomers working in the infrared and could help make better observations of the composition of the universe with the James Webb Space Telescope and other instruments.

     (via sciencedaily.com)     Original source 

Perovskite solar cells (PSCs) are considered a promising candidate for next-generation photovoltaic technology with high efficiency and low production cost, potentially revolutionizing the renewable energy industry. However, the existing layer-by-layer manufacturing process presents challenges that have hindered the commercialization of this technology. Recently, researchers have developed an innovative one-step solution-coating approach that simplifies the manufacturing process and lowers the commercialization barriers for PSCs.

     (via sciencedaily.com)     Original source 

Organic solar cells show great promise for clean energy applications. However, photovoltaic modules made from organic semiconductors do not maintain their efficiency for long enough under sunlight for real world applications. Scientists have now revealed an important reason why organic solar cells rapidly degrade under operation. This new insight will drive the design of more stale materials for organic semiconductor-based photovoltaics, thus enabling cheap and renewable electricity generation.

     (via sciencedaily.com)     Original source 

Hybrid perovskites are organic-inorganic molecules that have received a lot of attention over the past 10 years for their potential use in renewable energy. Some are comparable in efficiency to silicon for making solar cells, but they are cheaper to make and lighter, potentially allowing a wide range of applications, including light-emitting devices. However, they tend to degrade way more readily than silicon when exposed to moisture, oxygen, light, heat, and voltage. Researchers used machine learning and high-throughput experiments to identify perovskites with optimal qualities out of the very large field of possible structures.

     (via sciencedaily.com)     Original source 

A tiny biobattery that could still work after 100 years has been developed.

     (via sciencedaily.com)     Original source 

Global experts on solar power strongly urge a commitment to the continued growth of photovoltaic (PV) manufacturing and deployment to power the planet, arguing that lowballing projections for PV growth while waiting for a consensus on other energy pathways or the emergence of technological last-minute miracles 'is no longer an option.'

     (via sciencedaily.com)     Original source 

Researchers are studying radical new ways to improve solar power and provide more options for the industry to explore. Chemists are proposing to make solar cells using not silicon, but an abundantly available natural material called molybdenum disulfide. Using a creative combination of photoelectrochemical and spectroscopic techniques, the researchers conducted a series of experiments showing that extremely thin films of molybdenum disulfide display unprecedented charge carrier properties that could someday drastically improve solar technologies.

     (via sciencedaily.com)     Original source 

A star's chemical composition strongly influences the ultraviolet radiation it emits into space and thus the conditions for the emergence of life in its neighborhood.

     (via sciencedaily.com)     Original source 

Hydrogen, derived from polymer electrolyte fuel cells (PEFCs), is an excellent source of clean energy. However, PEFCs require platinum (Pt), which is a limited resource. Some studies have shown that Pt nanoclusters (NCs) have higher activity than conventionally used Pt nanoparticles, however the origin of their higher activity is unclear. Now, researchers have synthesized a novel Pt NC catalyst with unprecedented activity and identified the reason for its high performance.