The grain-boundary character distribution (GBCD) of undoped MgO has been measured and compared with samples containing small concentrations of Ca, Sr, Ba, and Y. Auger electron spectroscopy measurements of intergranular fracture surfaces verified that Ca, Ba, and Y segregated anisotropically to grain boundaries (GBs). The segregation of Sr was not detected. The GBCDs of Ca, Ba, and Y doped MgO ...

More abundant and economically friendly Sr-doped praseodymium ferrites show an increase in the electrocatalytic activity as amount of Sr dopant increases that is linked to increasing concentration oxygen vacancy.

Studying carbon, with its many allotropes and compounds, is one of the most fascinating problems in science. To mention only physics, before graphene, which was awarded the Nobel prize in 2010 opening exciting perspectives for fundamental and applied research, many other systems, such as nanotubes, fullerenes and intercalated graphites have played an important role in several fields, including ...

The problem of soot emissions from diesel engines is introduced and the possible solution of combining doped perovskites and microwave (mw) irradiation to "clean up" diesel soot filters is outlined. Eighteen doped perovskite catalysts are synthesized and tested for propane and CO oxidation, which are taken as model components for soot. The activity, selectivity, and SO2 tolerance are compared u...

Amorphous LaAlO3 films were deposited on hydrogen-terminated silicon substrates by atomic layer deposition (ALD) at 300 o C. The precursors were lanthanum tris(N,N’-diisopropylformamidinate), trimethylaluminum (TMA) and water. Capacitance-voltage measurements made on ALD MoN/LaAlO3/Si stacks showed humps especially at low frequencies. They were effectively removed by O2 treatment at 300 o C wit...

Sr Cu O ladder compounds contain linear frag ments of copper oxide planes In contrast to the two dimensional antiferromagnetic cuprates the spin two leg ladders have short range magnetic order and a spin gap Holes doped into these ladders pair and superconduct at high doping concentrations while insulators are known to result from low hole concen trations The competition between insulating stat...

We investigate the origin of the optical ac and dc conductivity anisotropies observed in the low temperature orthorhombic phase of lightly doped, untwinned La(2 - x)Sr(x)NiO(4) single crystals. We show that these anisotropies can be naturally ascribed to the emergence of two odd parity, rotational-symmetry-broken, localized impurity acceptor states, one deeper and one shallower, resulting from ...

Polarization-resolved terahertz (THz) time-domain spectroscopy was utilized to examine the complex refractive index of lanthanum aluminate (LaAlO3), a rhombohedrally distorted perovskite that exhibits crystallographic twin domains. The uniaxial anisotropy of the refractive index was quantified. The ellipticity of THz radiation pulses after transmission through single domains indicated that LaAl...