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A D V A N C E D M A T E R I A L S & P R O C E S S E S | O C T O B E R 2 0 1 8 1 3 EMERGING TECHNOLOGY NANOGALVANIC ALUMINUM POWDER HEADS TO MARKET The U.S. Army Research Labora- tory (ARL), Aberdeen Proving Ground, Md., plans to license its discovery of a nanogalvanic aluminum powder for hydrogen generation. Army researchers developed a structurally stable, alumi- num-based nanogalvanic alloy powder that, when combined with water or any water-based liquid, reacts to produce on-demand hydrogen for power gener- ation without a catalyst. “This powder-based alloy in- cludes material that disrupts the for- mation of an encapsulating aluminum oxide layer, allowing for the continu- ous production of hydrogen that can be used at the point of need to power a wide range of devices via fuel cells and internal combustion,” explains staff scientist Anit Giri. “The powder can be easily manufactured to scale, and can be convenient- ly and safely transport- ed via tablets or vac- uum pouches, thus elimi- nating reliance on high- pressure hydrogen cylin- ders.” To learn more about how the laboratory will se- lect the most appropriate partners and collaborators for commercialization pur- poses, visit arl.army.mil/ alnanogalvanicpowder. SOLAR CELL COMBO ATTAINS RECORD EFFICIENCY Silicon-based solar cells make up 90% of the market due to their stabili- ty, efficiency, and low cost. However, after decades of research, these cells are close to their maximum theoreti- cal efficiency and new ideas are need- ed to move the industry forward. One concept is to place two different types of solar cells on top of each other to maximize conversion of light rays into electrical power. These double-junction cells are being widely researched in the scientific community, but are expensive to make. Now, research teams from the Federal Polytechnic School of Laus- anne (EPFL) Photovoltaics Laboratory and the CSEM PV-center, Switzerland, report development of an economi- cally competitive solution. They have integrated a perovskite cell directly on top of a standard silicon-based cell, obtaining a record efficiency of 25.2%. Perovskite allows high conversion effic- ENER Y TRE DS Scanning electron microscopy image of silicon pyramids covered with perovskite. Courtesy of EPFL. iency to be achieved at a potential- ly limited production cost. In tandem cells, perovskite complements silicon: It converts blue and green light more efficiently, while silicon is better at con- verting red and infrared light. By com- bining the two materials, researchers say, use of the solar spectrum can be maximized and the amount of power generation increased. The new tandem cell is highly ef- ficient and directly compatible with monocrystalline silicon-based technol- ogies, which benefit from long-stand- ing industrial expertise and are already being produced profitably. Researchers say manufacturers won’t be required to adopt a whole new solar technology, but will simply need to update exist- ing production lines for silicon-based cells. This process would involve add- ing a few specific stages, say scientists. Work remains before the new technol- ogy could be adopted commercially. www.epfl.ch , csem.ch/pv-center. The DOE and the Israeli Energy Ministry signed an implementation agreement in June to establish the U.S.-Israel Center of Excellence in Energy, Engineering and Water Technology. The new center aims to accelerate development of criti- cal technologies for fossil energy, energy storage, and other initiatives required to diversify the energy supply and promote higher efficiency. energy.gov. BRIEF Army researcher Anthony Roberts works with the aluminum nano powder to release hydrogen during a chemical reaction. From left, U.S. Energy Secretary Rick Perry and Israeli Minister of Energy Yuval Steinitz. Courtesy of Shmulik Almany.