Piezoelectricity is a unique property of materials that permits the conversion of mechanical stimuli into electrical and vice versa. On the basis of crystal symmetry considerations, pristine carbon nitride (C3N4) in its various forms is non-piezoelectric. Here we find clear evidence via piezoresponse force microscopy and quantum mechanical calculations that both atomically thin and layered grap...

The microstructure and phase composition of the high-content Al2O3-Y2O3-doped spark plasma-sintered silicon nitride were investigated. Fully dense silicon nitride ceramics with a typical α-Si3N4 equiaxed structure with average grain size from 200 to 530 nm, high elastic modulus of 288 GPa, and high hardness of 2038 HV were spark plasma sintered (SPSed) at 1550 °C. Silicon nitride with elongated...

Since their inception, micro-size light emitting diode (µLED) arrays based on III-nitride semiconductors have emerged as a promising technology for a range of applications. This paper provides an overview on a decade progresses on realizing III-nitride µLED based high voltage single-chip AC/DC-LEDs without power converters to address the key compatibility issue between LEDs and AC power grid in...

An equilibrium Y-Si-0-N melt was infiltrated to eliminate the open porosity of reaction-bonded silicon nitride at 16001800°C. This oxynitride melt contained two equilibrium phases, a P-Si,N, solid phase and a liquid phase at high temperatures. Before infiltration, porous reaction-bonded silicon nitride compacts were heat-treated to completely transform to the P-Si3N, phase. After infiltration, ...

The title compound, [Mn(C48H36N4)(N)], is a manganese(V) complex with the transition metal in a square-pyramidal coordination geometry and a nitride as the axial ligand. The complex resides on a crystallographic inversion center and only one half of it is symmetry independent. The Mn(V) atom and the nitride N atom are equally disordered across the inversion center. The Mn N distance is 1.516 (4...

Titanium nitride is considered a promising alternative plasmonic material and is known to exhibit localized surface plasmon resonances within the near-infrared biological transparency window. Here, local heating efficiencies of disk-shaped nanoparticles made of titanium nitride and gold are compared in the visible and near-infrared regions numerically and experimentally with samples fabricated ...

Since 1994, the Applied Physics Laboratory has been collaborating with NASA Goddard Space Flight Center to develop photodetectors based on gallium nitride and aluminum gallium nitride material produced in the Milton S. Eisenhower Research and Technology Development Center. This article describes the results of our collaboration and highlights the development of gallium nitride photodetectors wi...

Scandium nitride (ScN) is a semiconducting transition metal nitride for which there are not identified dopants. We present local density functional calculations, in supercell approach, for ScN doped with O and C in N-sites and Ca and Ti in Sc-sites. Small additions of these atoms have the effect of shifting the Fermi level within the electronic band structure. O and Ti bring occupied states in ...

We report results from cathodoluminescence spectroscopy of boron nitride films grown on Si(100) substrates by ion-source-assisted magnetron sputtering of a hexagonal BN target. Three main peaks are observed in the near-band-gap region for hexagonal boron nitride films at energies of 4.90,5.31, and 5.50 eV We also report deep-level emission spectra of predominantly cubic boron nitride films whic...

Multiwall carbon nanotube (MWNT) reinforced silicon nitride ceramics matrix composites have been prepared. The hot isostatic press (HIP)-sintering method was used for composite processing. Bending strength and elastic modulus of MWNT-silicon nitride composites showed a considerable improvement compared to matrices with added carbon fiber, carbon black or graphite. However, the silicon nitride s...