Related papers: Bulk High-Entropy Hexaborides
Developing nanostructured bulk ceramics is a major challenge when conventional high-temperature sintering is employed for consolidation. In the current investigation, yttria-stabilized zirconia (YSZ) with a composition of ZrO2 - 3 mol% Y2O3…
The binary metal borides provide a promising platform for searching unique materials with superconductivity and super-hardness under high pressure, owing to the distinctive bonding characters of boron. In this work, combined the…
The Vickers hardness of polycrystalline {\gamma}-B was measured using a diamond indentation method. The elastic properties of polycrystalline {\gamma}-B (B=213.9 GPa, G=227.2 GPa, and E=503.3 GPa) were determined using ultrasonic…
The orthorhombic phase of Si-doped Fe carbide is synthesized at high pressures and temperatures using laser-heated diamond anvil cell (LHDAC), followed by its characterization using X-ray diffraction (XRD) measurements, Transmission…
LaB6 has been used as a commercial electron emitter for decades. Despite the large number of studies on the work function of LaB6, there is no comprehensive understanding of work function trends in the hexaboride materials family. In this…
Bending and vibration tests performed inside the scanning electron microscope were used to mechanically characterize high-aspect pillars grown by focused electron-beam (FEB) induced deposition from the precursor Cu(C5HF6O2)2. Supported by…
A novel carbon allotrope, hexagonal C12, is proposed from crystal chemistry and quantum density functional theory DFT calculations of ground state and physical properties. The structure exhibits corner sharing distorted tetrahedra with the…
A highly stable tungsten triboride with the Pearson symbol hP24 (hP24-WB3) is identified by using density functional theory calculations. This new structure can be derived from the well-known hP3 configuration by removing one third of…
The $1s^2->1s2p(^1P)$ excitation in confined and compressed helium atoms in either the bulk material or encapsulated in a bubble is shifted to energies higher than that in the free atom. For bulk helium, the energy shifts predicted from…
We have carried out bulk-sensitive hard x-ray photoelectron spectroscopy (HAXPES) measurements on in-situ cleaved and ex-situ polished SmB6 single crystals. Using the multiplet-structure in the Sm 3d core level spectra, we determined…
Transition metal nitrides have been suggested to have both high hardness and good thermal stability with large potential application value, but so far stable superhard transition metal nitrides have not been synthesized. Here, with our…
Single crystals of novel orthorhombic (space group Pnnm) iron tetraboride FeB4 were synthesised at pressures above 8 GPa and high temperatures. Magnetic susceptibility measurements demonstrated bulk superconductivity below 2.9 K. The…
Bulk MgB2 - based materials with the following critical current densities (jc) in 1 T field: 570 kA/cm^2 at 10 K, 350 kA/cm^2 at 20 K and 40 kA/cm^2 at 30 K and in 10 T field: 650 A/cm^2 at 10 K have been high-pressure (HP) synthesized from…
The mass density of nanowires is determined using in-situ resonance frequency experiments combined with quasi-static nanotensile tests. Our results reveal a mass density of 7.36 g/cm3 on average which is below the theoretical density of…
Isotropic bonded magnets with a high loading fraction of 70 vol.% Nd-Fe-B are fabricated via an extrusion-based additive manufacturing, or 3D printing system that enables rapid production of large parts for the first time. The density of…
We report on the results of a comparative investigation of highly dense bulk MgB$_2$ samples prepared by three methods: (i) hot deformation; (ii) high pressure sintering; and (iii) mechanical alloying of Mg and B powders with subsequent hot…
A series of dual-phase high-entropy ultrahigh temperature ceramics (DPHE-UHTCs) are fabricated starting from N binary borides and (5-N) binary carbides powders. >~99% relative densities have been achieved with virtually no native oxides.…
Bulk textured MgB_2 material of nearly full density showing a weak c-axis alignment of the hexagonal MgB_2 grains parallel to the pressure direction was obtained by hot deformation of a stoichiometric MgB_2 pellet prepared by a gas-solid…
We present new narrow-band filter imagery in H-alpha and [N II] 6584 along with UV and optical spectrophotometry measurements from 1200 to 9600 Angstroms of NGC 7293, the Helix Nebula, a nearby, photogenic planetary nebula of large diameter…
We predict that plutonium hexaboride (PuB6) is a strongly correlated topological insulator, with Pu in an intermediate valence state of Pu^2.7+ . Within the combination of dynamical mean field theory and density functional theory, we show…