Overcoming a critical conductivity challenge to clean energy technologies, Boston College researchers have developed a titanium nanostructure that provides an expanded surface area and demonstrates significantly greater efficiency in the transport of electrons.
The challenge has vexed researchers pursuing solar panels thick enough to absorb sunlight, yet thin enough to collect and transport electrons with minimal energy loss. Similarly, the relatively new science of water splitting requires capturing energy within semiconductor materials and then efficiently transporting charges ultimately used to generate hydrogen.Boston College Asst. Prof of Chemistry Dunwei Wang and members of his lab found that incorporating two titanium-based semiconductors into a nano-scale structure improved the efficiency of power-collecting efforts by approximately 33 percent, the team reported in the online edition of the Journal of the American Chemical Society.
Wang said the efficiency gains within the novel material can serve so-called water-splitting, where semiconductor catalysts have been shown to separate and store hydrogen and oxygen gases.
"The current challenge in splitting water involves how best to capture photons within the semiconductor material and then grab and transport them to produce hydrogen," Wang says. "For practical water splitting, you want to generate oxygen and hydrogen separately. For this, good electrical conductivity is of great importance because it allows you to collect electrons in the oxygen-generation region and transport them to the hydrogen-generation chamber for hydrogen production."
By using two crystalline semiconductors – materials critical to the processes of energy capture and transport – Wang says the researchers discovered a new and successful transfer mechanism in an engineered structure nearly invisible to the human eye.
Titanium dioxide has played a key role in early water-splitting research because of its prowess as a catalyst. However, its light absorption is confined to ultraviolet rays only and the material is also a relatively poor conductor.
Wang and his researchers started by growing a nanostructure made of titanium disilicide (TiSi2), a semiconductor capable of absorbing solar light and a material able to provide a sturdy structure with expanded surface area critical to absorbing photons. Still in need of its catalytic capabilities, titanium dioxide was used to coat the structure, Wang said.
The resulting net-like nanostructure effectively separated charges, collecting the electrons in the titanium disilicide core and transporting them away. The structure transferred positive charges to the titanium dioxide region of the material for chemical reactions. In water-splitting, these charges could potentially be used to generate hydrogen.
Don't Give the Slightest Chance to Toxic Elements in Medicinal Products
23.03.2018 | Physikalisch-Technische Bundesanstalt (PTB)
North and South Cooperation to Combat Tuberculosis
22.03.2018 | Universität Zürich
Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.
The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...
An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...
In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
23.03.2018 | Event News
19.03.2018 | Event News
16.03.2018 | Event News
23.03.2018 | Life Sciences
23.03.2018 | Materials Sciences
23.03.2018 | Process Engineering