[Image above] Credit: NIST
While the cleaning of car exhausts is among the best known applications of catalytic processes, it is only the tip of the iceberg. Practically the entire chemical industry relies on catalytic reactions. Catalyst design plays a key role in improving these processes. An international team of scientists has now developed a concept that elegantly correlates geometric and adsorption properties. They validated their approach by designing a new platinum-based catalyst for fuel cell applications.
A group of researchers at Uppsala University has discovered a “zombie solar cell” that continues to generate electricity with unexpected effectiveness although the liquid transferring charges between the electrodes has dried out. When the researchers tested old dye-sensitized solar cells, also known as Grätzel cells, these were still active, despite the fact that the electrolyte conducting electricity between the minus and plus poles had evaporated.
Silicon wafers are the heart of solar cells. However, manufacturing them is not cheap. Over 50 percent of the pure silicon used is machined into dust. A new manufacturing technique developed by Fraunhofer researchers puts an end to these material losses, with raw material savings of 50 percent along with an 80 percent reduction in energy costs.
The efficiency of solar cells depends on precise engineering of polymers that assemble into films 1,000 times thinner than a human hair. Today, formation of that polymer assembly requires solvents that can harm the environment, but scientists at the Department of Energy’s Oak Ridge National Laboratory have found a “greener” way to control the assembly of photovoltaic polymers in water using a surfactant—a detergent-like molecule—as a template.
Researchers at The University of Alabama designed and made a material that manipulates the speed of light in a new, more effective way than previous methods. The researchers fabricated and measured subwavelength metal patterns they specially designed on top of a substrate, such as silicon, to create a flexible and thin metamaterial. The paper explaines how such a thin metamaterial can behave as if it was 1,000 times thicker, which makes highly integrated photonic sensors possible.
A group of researchers at Osaka University, in cooperation with Screen Holdings Co. Ltd., succeeded in visualizing changes in defect density on the surface of GaN through the laser terahertz emission microscope, which measures THz waves generated by laser emission. This discovery shows that LTEM is useful as a new method for evaluating the quality of wide-gap semiconductors.
Researchers at Chalmers University of Technology have arrived at how what is known as time-reversal symmetry can break in one class of superconducting material. A computational tool has allowed the Chalmers researchers to investigate cases where the ring of a superconducting crystal affects the force of the superconducting phase. A periodic pattern of vortices spontaneously forms in the shape of a necklace along the surface as soon as the temperature is lower than a limit temperature.