True structure of pnictide 122 superconductors revealed
April 13, 2015 — High-resolution microscopy revealed an unexpected room-temperature crystal structure of the ‘122’ Ba(Fe1-xCox)2As2 superconductors, with domains similar to those in ferroelectrics but with nanometer size.
New model predicts formation of stable high-entropy alloys
April 09, 2015 — Researchers devised a model that can predict which combinations of 5 or more elements will form new “high-entropy alloys.” This work, which utilizes values obtained from data mining of high-throughput calculations of binary compounds, requires no experimental or empirically derived input and advances capabilities for “materials by design.
Atomic-Scale Observations Aid Mesoscale Catalyst Design
April 08, 2015 — Two phases of Mo-V-O–based oxides, M1 and M2, are promising catalysts for direct conversion of propane to acrylonitrile and are believed to act synergistically. Researchers engineered the mesoscale structure of M1- and M2-phase oxides to amplify these effects, greatly improving selectivity for propane ammoxidation.
Technique Recovers Atomic Resolution in Spectrum Images
April 08, 2015 — Researchers have demonstrated a technique for obtaining atomic-resolution information from spectrum images of thick specimens of MnFePSi compounds, which are promising for ecofriendly refrigeration. This technique allows the quantitative examination of specimens for which atomic-resolution spectroscopic analysis was previously impossible.
World's Thinnest Proton Channel
March 18, 2015 — Graphene is a single-atom thin 2-dimensional array of carbon atoms that represents a barrier that is impenetrable even to protons unless graphene membrane has macroscopic holes.
Dynamic coupling drives conformational evolution of branched polymers in solutions
March 06, 2015 — The critical overlap concentration of polymer solutions, denoted c*, is one of the most important characteristic values of a polymer solution. This geometrically defined parameter is used to identify concentration regimes with different conformational characteristics.
Electronic Excitations Transform Structure of Ceramics
March 06, 2015 — Ab initio molecular dynamics calculations reveal that electronic excitations induce a structural instability that transforms Y2Ti2O7, Gd2Ti2O7 and Sm2Ti2O7 with the pyrochlore crystal structure to an amorphous state.
New Atomic Force Microscope Spectroscopy Probes Local Elasticity
March 04, 2015 — Contact resonance imaging and voltage spectroscopy based on photothermal excitation were developed to explore local bias-induced phenomena. These techniques can access nanoscale elastic properties in real time during polarization switching in ferroelectric nonvolatile memories, and during ion intercalation in batteries and supercapacitors.
Review Finds Ionization Can Heal or Harm Materials
February 06, 2015 — An invited review on latest advances in ion beam modification of materials provides conclusive evidence that energy loss by energetic ions to electrons (ionization) can lead to either self-healing of radiation damage created by atomic collisions or contribute to radiation damage.
Iodine-coordinated sulfide leads to an exceptionally stable ceramic electrolyte
February 04, 2015 — Coordination of iodine atoms within the Li3PS4 (LPS) electrolyte results in a new ceramic electrolyte with the formulation Li7P2S8I, a coordinated material between LPS and LiI. This new formulation takes advantage of the chemical stability of LiI to render an electrolyte with excellent compatability with Li anode.