Tag Archives: ultraviolet light beams

New Path to More Efficient Organic Solar Cells Uncovered at Berkeley Lab’s Advanced Light Source

Why are efficient and affordable solar cells so highly coveted? Volume. The amount of solar energy lighting up Earth’s land mass every year is nearly 3,000 times the total amount of annual human energy use. But to compete with energy from fossil fuels, photovoltaic devices must convert sunlight to electricity with a certain measure of efficiency. For polymer-based organic photovoltaic cells, which are far less expensive to manufacture than silicon-based solar cells, scientists have long believed that the key to high efficiencies rests in the purity of the polymer/organic cell’s two domains – acceptor and donor. Now, however, an alternate and possibly easier route forward has been shown.

Working at Berkeley Lab’s Advanced Light Source (ALS), a premier source of X-ray and ultraviolet light beams for research, an international team of scientists found that for highly efficient polymer/organic photovoltaic cells, size matters. (more…)

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Space-Age Ceramics Get Their Toughest Test:

Berkeley Lab Researchers Develop Real-Time CT-Scan Test Rig For Ceramic Composites at Ultrahigh Temperatures

Advanced ceramic composites can withstand the ultrahigh operational temperatures projected for hypersonic jet and next generation gas turbine engines, but real-time analysis of the mechanical properties of these space-age materials at ultrahigh temperatures has been a challenge – until now. Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have developed the first testing facility that enables CT-scanning of ceramic composites under controlled loads at ultrahigh temperatures and in real-time.

Working at Berkeley Lab’s Advanced Light Source (ALS), a premier source of X-ray and ultraviolet light beams, the scientists created a mechanical testing rig for performing X-ray computed microtomography that reveals the growth of microcrack damage under loads at temperatures up to 1,750 degrees Celsius. This allows engineers to compute a ceramic composite material’s risk of structural or mechanical failure under extreme operating conditions, which in turn should enable the material’s performance and safety to be improved. (more…)

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