Using novel materials to develop thin, flexible, and more efficient photovoltaic cells is one of the hottest topics in current materials research. A class of transition metals undergoes a dramatic change that makes them ideal for solar energy applications. Read more »
ALS Work Using Spectroscopy
These techniques are used to study the energies of particles that are emitted or absorbed by samples that are exposed to the light-source beam and are commonly used to determine the characteristics of chemical bonding and electron motion.
Learning from Roman Seawater Concrete
Analyses of ancient concrete samples pinpointed why the best Roman concrete was superior to most modern concrete in durability, why its manufacture was less environmentally damaging, and how these improvements could be adopted in the modern world. Read more »
New Light on a Famous Insulator: Photoinduced Polaronic Conduction in Anatase
Using angle-resolved photoemission spectroscopy (ARPES), researchers have shown that the number of conduction electrons in anatase, as well as their degree of correlation, can be patterned by exposure to UV light in a controllable and reversible way. Read more »
Chemistry of Cobalt-Platinum Nanocatalysts
Bimetallic cobalt-platinum (CoPt) nanoparticles are drawing attention in many areas of catalysis as scientists tackle the quest to reduce precious metal content while maintaining optimum catalytic selectivity and reactivity. Researchers explored the role of Pt in Co reducing and oxidizing, and found that the catalytic properties of monometallic and bimetallic nanoparticles of Co are closely related to the oxidation state of Co. Read more »
Chloride Depletion in Aged Sea Salt Particles
Elemental and chemical imaging analyses showed that sea salt particles react with water-soluble organic acids in the atmosphere through a unique mechanism which had been overlooked in atmospheric chemistry. The reactions release volatile hydrogen chloride into the atmosphere and leave behind sea salt particles drained of chloride.
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Two Electron Holes in Hematite Facilitate Water Splitting
Hematite is a promising electrode material for solar-powered water splitting—an important reqirement for producing hydrogen fuel with zero emissions. At Beamline 7.0.1, researchers have gained a better understanding of hematite’s electronic structure through soft x-ray spectroscopy performed in situ and “operando.” Read more »
Direct Kinetic Measurements of a Criegee Intermediate
“Criegee intermediates” are elusive molecules that play a pivotal role in atmospheric chemistry and are also byproducts of key combustion reactions. At the Chemical Dynamics Beamline, the reaction rates of one form of Criegee intermediate was directly measured for the first time, with some surprising results. Read more »
ALS Reveals New State of Matter
ALS user groups from Princeton and Stanford have been making waves this past year with several high-profile papers and extensive news coverage of their work on a new state of matter embodied by so-called “topological insulators,” materials that conduct electricity only on their surfaces. Read more »
Molecular Measurements of the Deep-Sea Oil Plume in the Gulf of Mexico
To study the effects of oil spilled from the Deepwater Horizon blowout, researchers collected deep-water samples from across the Gulf of Mexico and analyzied their physical, chemical, and microbiological properties using a variety of techniques, including SR-FTIR. Read more »
Platinum Nanoclusters Out-Perform Single Crystals
Researchers have found that under high pressure—comparable to the pressures at which many industrial technologies operate—platinum surfaces can change their structure dramatically in response to the presence of high-coverage reactants. Read more »