Because of the strong electron-phonon coupling of the emitting 3d orbitals in transition-metal (TM) ions, 3d systems exhibit luminescence with typically several hundred nm of spectral bandwidth. TM-ion-doped materials are, therefore, of high interest for applications as tunable and short-pulse lasers. Whereas many TM-ion-doped systems suffer from excited-state absorption (ESA), systems with a d...

The efficiency of Co(II)-, Mn(II)-, and Ti(IV)-doped carbon aerogels for the transformation of ozone into (*)OH radicals was investigated. The carbon aerogels had a markedly acid surface character (pH(PZC approximately equal) congruent with 3-4) with very high surface oxygen concentrations (O approximately equal with 20%). X-ray photoelectron spectroscopy (XPS) analyses of the samples showed th...

We have performed an in-situ depth profile study of Mn-doped GaN prepared by a low temperature thermal diffusion method using photoemission and x-ray absorption spectroscopy. It was revealed from the core-level pho-toemission measurements that Mn ions are diffused into a deep (∼ 70Å) region of the GaN substrates and that the line shapes of Mn 3d partial density of states obtained by resonant ph...

We have investigated the energetic properties of Mn-doped MgO bulk and (100) surfaces using a QM/MM embedding computational method, calculating the formation energy for doped systems, as well as for surface defects, and the subsequent effect on chemical reactivity. Low-concentration Mn doping is endothermic for isovalent species in the bulk but exothermic for higher oxidation states under p-typ...

Relative K x-ray intensities of Mn in Mn, MnO2, LaMnO3 and La0.7B0.3MnO3 (B = Ca, Sr, and Ce) systems have been measured following excitation by 59.54 keV γ-rays from a 200 mCi Am point-source. The measured results for the compounds deviate significantly from the results of pure Mn. Comparison of the experimental data with the multiconfiguration DiracFock (MCDF) effective atomic model calculati...

Background: A simple hydrothermal process was applied to synthesize the doped TiO2 particles with different concentrations as well as different metal ions (Mn, Ce and La). Methods: The synthesis of Mn-doped-TiO2 nanoparticles was done by using a hydrothermal method from hydrolysis of titanium tetrachloride in aqueous solution. The photocatalytic activities were checked by studying the degradati...

In this work, redox-active Mn or Cr is introduced to the B site of redox stable perovskite Sr(0.95)Ti(0.9)Nb(0.1)O3.00 to create oxygen vacancies in situ after reduction for high-temperature CO2 electrolysis. Combined analysis using X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric analysis confirms the change of the chemical formula fro...

Undoped and Mn-doped ZnO nanoparticles were successfully prepared by the hydrothermal method with different annealing temperature conditions. Structural, chemical and optical properties of the samples were studied by X-ray diffraction (XRD), Field Emission scanning electron microscopy (FESEM), UV-Vis spectrophotometry and Fourier transform infrared (FT-IR) spectroscopy. The phase purity was con...

We report on a controlled ambient annealing technique aimed at increasing the amount of Mn incorporation in III–V semiconductors. The aim is to reduce the number of hole carrier and magnetic element compensating entities, such as Mn interstitials and anti-site defects, to increase the magnetic Curie temperature. The idea is (a) to increase the number of Group III vacancies through annealing in ...

Using first-principles calculations based on gradient corrected density functional theory we show that an otherwise distorted icosahedric Mn(13) ferrimagnetic cluster, when doped with six B or C atoms, transforms into a ferromagnetic cuboctahedral cluster with a magnetic moment that is an order of magnitude larger than that of the pure Mn(13) cluster. The origin of this magnetic transition is a...