Electronic structure measurements using x-ray absorption spectroscopy suggest that oxygen vacancies contribute to the metal–insulator transition in ultrathin films of LaNiO3. The results give scientists another “knob” to turn to tune this important transition, which could be useful for making advanced electronic devices. Read more »
Molecular Anvils Trigger Chemical Reactions
“Molecular anvils” (diamondoids) were used to trigger chemical reactions using pressure, yielding products that differ from those produced in conventionally driven reactions with the same reactants. The discovery opens up new possibilities for the high-specificity synthesis of valuable but challenging molecules in an environmentally friendly process. Read more »
Non-Crystal Clarity: Scientists Find Ordered Magnetic Patterns in Disordered Magnetic Material
Scientists have confirmed the presence chirality, or handedness, in nanometers-thick samples of amorphous (noncrystalline) multilayer materials. The chirality—which potentially could be exploited to transmit and store data in a new way—was observed in the domain walls between neighboring regions of opposite spin. Read more »
Clarifying the Working Principle of a High-Capacity Battery Electrode
Operando x-ray absorption spectroscopy experiments revealed the electrochemical reaction mechanism of molybdenum disulfide (MoS2) electrodes in lithium-ion battery cells. The work unambiguously clarifies that the MoS2 conversion reaction is not reversible and that the Li2S formed is converted to sulfur in the first charge process. Read more »
Monovalent Manganese for High-Performance Batteries
Scientists have detected a novel chemical state of the element manganese that was first proposed about 90 years ago. The discovery enables the design of a high-performance, low-cost battery that, according to its developers, outperforms Department of Energy goals on cost and cycle life for grid-scale energy storage. Read more »
X-Ray Handedness Reveals Handedness of Electronic Vortices
Electronic vortex structures have been found to emerge from engineered samples of alternating complex-oxide layers. Resonant soft x-ray diffraction (RSXD) studies using circularly polarized x-rays revealed the vortices’ left- and right-handedness. The intriguing results open the door to electrically controllable chiral devices. Read more »
Tuning Magnetic Frustration in a Dipolar Trident Lattice
Researchers designed and fabricated a nanomagnet array in which competing (“frustrated”) magnetic interactions can be directly tuned. Frustrated interactions are key to a wide range of phenomena, from protein folding and magnetic memory to fundamental studies of emergent exotic states. Read more »
Dmitriy Voronov Receives Klaus Halbach Award
The 2017 Klaus Halbach Award for Innovative Instrumentation at the ALS was recently awarded to ALS Staff Scientist Dmitriy Voronov “for pioneering work in the area of advanced x-ray gratings.” The research that led up to Voronov’s award began about 10 years ago when he started at the ALS in the Experimental Systems Group with Howard Padmore. Read more »
X-Ray Footprinting Solves Mystery of Metal-Breathing Protein
Scientists have discovered the details of an unconventional coupling between a bacterial protein and a mineral that allows the bacterium to breathe when oxygen is not available. The research could lead to innovations in linking proteins to other materials for bioelectronic devices such as sensors that can diagnose disease or detect contaminants. Read more »
Scientists Solve a Magnesium Mystery in Rechargeable Battery Performance
Rechargeable batteries based on magnesium, rather than lithium, have the potential to pack more energy into smaller batteries. However, researchers have discovered a surprising set of chemical reactions involving magnesium that degrade battery performance even before the battery can be charged up. Read more »
