Research Highlights

Research Highlights

 residual stress illustration

Measuring residual stress in nuclear waste canisters

Neutron analysis revealed residual stress in welded stainless-steel canisters. Credit: Oak Ridge National Laboratory/Department of Energy (hi-res image) Researchers used neutron diffraction to map residual stress in stainless steel canisters that store spent nuclear...
Oak Ridge National Laboratory

Quantum critical behavior in a concentrated solid solution: a new twist on structural alloys

Concentrated transition metal alloys with the formula NiCoCrx, with x≈1, and a simple cubic crystal structure, display transport, magnetic and thermodynamic signatures exhibited by more structurally complex compounds near a quantum critical point (QCP). These alloys provide...
Oak Ridge National Laboratory

Strategy shown for novel tire-derived carbon anodes for sodium-ion batteries

Researchers have demonstrated a process to prepare morphologically tailored carbon materials with good electrochemical capacity Shown are scanning transmission electron microscopy of sulfonated tire-derived carbon treated at 1,100oC (left) and data from a long-...
Oak Ridge National Laboratory

Synthesis of two-dimensional GaSe/MoSe2 misfit heterojunctions by van der Waals epitaxy

Misfit heterojunctions formed by van der Waals (vdW) epitaxial growth of one crystalline metal chalcogenide monolayer on anotherwas demonstrated for the first time to form p-n junctions that exhibit a photovoltaic response.  Such heterojunction bilayers that display Moiré...
Oak Ridge National Laboratory

Doping strengthens magnetism in an iron-based crystal

Thallium-doping (5%) of BaFe2As2 crystal causes a surprising rise of the antiferromagnetic transition temperature (TN), related to Temperature-dependent heat capacity for Ba1-xTlxFe2As2shows an increase in magneto-elastic anomaly at 5...
Oak Ridge National Laboratory

Single axis strain provides a new level of control over optical bandgap

Helium implantation allows for continuous control of optical band gaps in semiconducting films through the resultant strain — an impossibility Inserting helium atoms into a crystalline film allows for fine control over the elongation of the out-of-plane axis. This is shown to...
Oak Ridge National Laboratory

Single axis strain provides a new level of control over optical bandgap

Helium implantation allows for continuous control of optical band gaps in semiconducting films through the resultant strain — an impossibility Inserting helium atoms into a crystalline film allows for fine control over the elongation of the out-of-plane axis. This is shown to...
Oak Ridge National Laboratory

Dramatic Compositional Effects on Transport in Concentrated Solid Solution Alloys

Compositional complexity is found to strongly affect electrical, thermal, and magnetic properties of nickel-containing face-centered (Left) Increasing compositional complexity (especially when alloying with Cr) enhances the electrical resistivity. (Right) The thermal...
Oak Ridge National Laboratory

Compositional Complexity Effectively Modifies Defect Migration Barriers

Compared to pure nickel, tuning chemical composition in binary alloys has altered migration barriers of defects, and significantly affected  Cross-sectional transmission electron microscopy images of Ni, NiCo and NiFe showing irradiation-induced damage is much deeper in Ni, as...
Oak Ridge National Laboratory

Epitaxial Strain Activates Oxygen in Complex Oxides

Researchers demonstrated that straining the crystal lattice of strontium cobaltite reduces oxygen content even under highly oxidizing conditions, The schematic represents strain control of oxygen stoichiometry in a SrCoO3-δ epitaxial thin film. Tensile strain is found to...
Oak Ridge National Laboratory

Giant Spin-Driven Electric Polarization is Revealed in Promising Multiferroic

Multiferroic materials are important because their electrical and magnetic properties are coupled.  Because BiFeO3 magnetically Comparison between the predicted and observed spin-driven polarization (above) and of the octahedral rotation angle AFD (below) are...
Oak Ridge National Laboratory

Single-atom catalysts may cut costs for green technologies

Researchers discovered that isolated platinum atoms in copper surfaces efficiently catalyze the selective hydrogenation of 1,3 butadiene, a reaction important for many industrial applications.1 A new generation of catalysts with one Pt atom for approximately every 100 Cu atoms...
Oak Ridge National Laboratory

Controlling nobility: making reactive palladium inert

While palladium, a common catalyst, oxidizes easily, it has now been shown that palladium films grown on ruthenium are surprisingly inert to Surface oxygen concentration for palladium films of different thicknesses after exposure to oxygen. Films with a thickness less than...
Oak Ridge National Laboratory

Easy phase transitions spur high piezoelectric responses

Theoretical calculations, based on newly obtained experimental geometries in strained BiFeO3 thin films, predict an almost barrierless Electronic structure theory demonstrates that no barrier exists along the path between co-existing phases in compressively...
Oak Ridge National Laboratory

ORNL's Plasma-arc lamp tests instrument for NASA solar probe

To test a key instrument of a spacecraft that will fly closer to the sun than any before, engineers at Oak Ridge National Laboratory and the University of California–Berkeley used ORNL’s powerful plasma-arc lamp as a solar heat flux simulator. They tested the Fields instrument, which will...
Oak Ridge National Laboratory

Researchers craft recipe for polymer with a memory for shape

A new plastic developed by ORNL and Washington State University transforms from its original shape (left) through a series of temporary shapes and returns to its initial form. The shape-shifting process is controlled through changes in temperature. (hi-res image)...

Filter Highlights

» Clear Filter Selections

Researchers