[Image above] Credit: NIST
Imperfections running through liquid crystals can be used as miniscule tubing, channeling molecules into specific positions to form new materials and nanoscale structures, according to engineers at the University of Wisconsin-Madison. So far, researchers have been able to assemble phospholipids within liquid crystal defects. Their technique may also be useful for assembling metallic wires and various semiconducting structures vital to electronics.
CIGS (copper-indium-gallium-selenide) solar cells are compound thin-film solar cells and the most established alternative to silicon solar cells. Solar conversion efficiencies of over 20% have recently been achieved in CIGS solar cells. Researchers at Toyohashi University of Technology, in collaboration with researchers at the National Institute of Advanced Industrial Science and Technology, have analyzed the structure of a zinc-based buffer layer in a CIGS solar cell via synchrotron radiation, which revealed the structure of the buffer layer and identified a way to improve the conversion efficiency.
What’s the best sunscreen? It’s a question that troubles beachgoers, athletes, and scientists alike. Mark Saltzman, who falls into the last category, was so concerned by the time his third child was born that he wanted to engineer a better sunblock. Now, he and his colleagues have unveiled the results of their research: a nanoparticle-based sunblock, which they say is longer lasting and less likely to leak into the body than traditional sunscreen.
Harvard researchers have designed new multimaterial printheads that mix and print concentrated viscoelastic inks that allow for the simultaneous control of composition and geometry during printing. Using active mixing and fast-switching nozzles, these novel printheads change material composition on the fly and could pave the way for entirely 3D-printed wearable devices, soft robots, and electronics.
Success of the energy turnaround will depend decisively on the extended use of renewable energy sources. However, their efficiency partly is much smaller than that of conventional energy sources. The efficiency of commercially available photovoltaic cells, for instance, is about 20%. Scientists of Karlsruhe Institute of Technology have now published an unconventional approach to increasing the efficiency of the panels. Optical invisibility cloaks guide sunlight around objects that cast a shadow on the solar panel, such as contacts for current extraction.
Chemists at Ludwig-Maximilians-Universitat Munchen and the Max Planck Institute have introduced a new class of porous organic materials that can be used as the basis for molecularly tunable photocatalysts for light-driven production of hydrogen gas. These materials are composed of layers of regular two-dimensional molecular networks synthesized from simple organic precursors, and they exhibit a number of features that facilitate photocatalytic processes.
An alloy first made nearly two decades ago by the U. S. Navy could provide an efficient new way to produce electricity. The material, dubbed Galfenol, consists of iron doped with the metal gallium. In new experiments, researchers from UCLA, the University of North Texas, and the Air Force Research Laboratories have shown that Galfenol can generate as much as 80 megawatts of instantaneous power per square meter under strong impacts.