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opportunity for the development of zeroemission vehicles with a driving range similar to that of gasoline vehicles," says Elton Cairns, of the Environmental Energy Technologies Division (EETD). "The lithium-sulfur battery chemistry has attracted attention because it has a much higher theoretical specific energy than lithium-ion batteries do," says Cairns. "Lithium-sulfur batteries would also be desirable because sulfur is nontoxic, safe and inexpensive," he adds. Li/S batteries would be cheaper than current Li-ion batteries, and they would be less prone to safety problems that have plagued Li-ion batteries, such as overheating and catching fire. The team is now seeking support for the continuing development of the Li/S cell, including higher sulfur utilization, operation under extreme conditions, and scale-up. Partnerships with industry are being sought. This research was funded by the US Department of Energy's Office of Science and a University of California's Proof of Concept Award. WATER SPLITTER FREES OXYGEN AND STORES HYDROGEN FOR FUEL California's Stanford University scientists have created a silicon-based water splitter that is both low-cost and corrosion-free. The novel device, a silicon semiconductor coated in an ultrathin layer of nickel, could help pave the way for large-scale production of clean hydrogen fuel from sunlight, according to the scientists. Their results are published in the November 15 issue of the journal Science. To produce clean hydrogen for fuel cells, scientists have turned to an emerging technology called water splitting. Two semiconducting electrodes are connected and placed in water. The electrodes absorb light and use the energy to split the water into its basic components – oxygen and hydrogen. The oxygen is released into the atmosphere DECEMBER/JANUARY 2014 RW December 2013.indd 59 and the hydrogen is stored as fuel.   To reverse the process, the stored hydrogen and atmospheric oxygen are combined in a fuel cell to generate electricity and pure water.  The process is sustainable and emits no greenhouse gases. But finding a cheap way to split water has been a major challenge. Researchers continue searching for inexpensive materials to build water splitters efficient enough to be of practical use. SCIENTISTS TRANSFORM DANDELION JUICE INTO NATURAL RUBBER The first modern pilot system for extracting large quantities of tire rubber from dandelions is being developed by researchers in Münster Germany at the Fraunhofer Institute for Molecular Biology and Applied Ecology IME, in cooperation with German auto parts maker, Continental AG [CONFWB; CTTAY-OTC]. The pilot project is possible due to a number of important improvements to cultivation and production engineering. Scientists from Fraunhofer have transformed the ordinary dandelion from a weed into an agricultural crop that produces an abundance of natural rubber. Photo © Fraunhofer IME. The first prototype test tires made with blends from dandelion-rubber are scheduled to be tested on public roads over the next few years. The natural product exhibited the same quality as the conventional rubber from rubber trees that have been imported from subtropical countries and used in tire production. However, unlike conventional rubber, it could be harvested more cost-effectively, better cultivated and grown in Germany as a sustainable raw material – even on land areas not previously suited for agricultural crops. "We are investing in this highly promising materials development and production project because we are certain that, in this way, we can further improve our tire production over the long term," says Nikolai Setzer, the Continental managing director who is responsible for the tires division. "It's because the rubber extraction from the dandelion root is markedly less affected by weather than the rubber obtained from the rubber tree. Based on its agricultural modesty, it holds entirely new potential – especially for cropland that is lying fallow today. This development project impressively demonstrates that, with regard to material development, we have not reached the end of our potential." "With this new technology, we can achieve a sustainable edge for the German automotive market. On the one hand, it makes the domestic economy less dependent on the importing of raw materials. On the other hand, it reduces the transportation routes, and thus improves the CO2 balance," as Dr.-Ing. Reimund Neugebauer, President of the Fraunhofer-Gesellschaft, describes the purpose and the essential advantages of the collaboration. The joint project officially started at the beginning of October. The goal is to develop the production process over the next five years so that Continental can then manufacture tires made from dandelion rubber. n www.resourceworld.com 59 12/11/2013 6:12 PM

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