Entries by Katy

Influence of matrix on the luminescence properties of Eu2+/Eu3+ doped strontium borates: SrB4O7, SrB2O4 and Sr3 (BO3) 2, exhibiting multicolor tunable emission

Three complex strontium borate matrices, i.e. Sr3(BO3)2, SrB2O4 and SrB4O7 doped with Eu2+/Eu3+ ions, were prepared by the solid state reaction method in the air. X-ray and SEM analyses confirmed that all these samples are pure phase micro-sized materials. The luminescence properties of the Eu2+ and Eu3+ doped compounds were investigated in detail, i.e. excitation and emission spectra, including luminescence […]

New multicomponent titanate-germanate glasses and their luminescence properties

New multicomponent titanate-germanate glasses were synthesized and their luminescence properties have been studied. The intense near-infrared luminescence bands are observed in titanate-germanate glass, which correspond to main laser transitions 4F3/2 → 4I11/2 (Nd3+), 4I13/2 → 4I15/2 (Er3+) and 5I7 → 5I8 (Ho3+) of rare earth ions. In particular, luminescence linewidths have been examined in relation to potential broadband near-infrared laser applications. To read more click here

Luminescence of 5d–4f transitions of Pr3+ in natural fluorite CaF2, anhydrite CaSO4 and apatite Ca5(PO4)3F

Natural fluorite, anhydrite and apatite under deep UV excitation exhibits several narrow emission bands in the spectral range of 225–300 nm with the strongest peaks at 230–240 nm and 260–290 nm and with half-widths of 20–30 nm. They are characterized by narrow excitation band peaking at 220 nm and very short decay times of 20–50 ns. Those spectral-kinetic parameters enable their […]

Lead of detection in rhododendron leaves using laser-induced breakdown spectroscopy assisted by laser-induced fluorescence

Laser-induced breakdown spectroscopy assisted by laser-induced fluorescence (LIBS-LIF) was applied to determine lead (Pb) in rhododendron leaves. Rhododendron leaves are essential types of herbal materials. Rapid detection of lead in rhododendron leaves is urgent for drug monitoring. In this paper, the powder method and solid-liquid-solid transformation (SLST) method were employed as sample preparation. The results […]

Halogen detection with molecular laser induced fluorescence

The detection of low halogen concentrations by atomic Laser Induced Breakdown Spectroscopy (LIBS) is usually difficult due to low intensity lines, which overlaps with matrix and due to an uncomfortable spectral region. Molecular LIBS (MLIBS) based on diatomic molecules of halogens with alkali earth element emission substantially increases sensitivity for halogen detection. We demonstrate that […]

Theoretical calculations and experimental investigations of lead phosphate glasses singly doped with Pr3+ and Tm3+ ions using luminescence spectroscopy

Lead phosphate glasses singly-doped with selected Ln3+ ions (Ln = Pr, Tm) were prepared by traditional melt-quenching method. The effect of concentration of optical active dopants in glass composition on spectroscopic properties of lead phosphate glasses were systematically investigated based on excitation, visible and near-infrared emission spectra as well as luminescence decay analysis. It was found that the […]

TiO2-reduced graphene oxide nanocomposites: Microsecond charge carrier kinetics

In this work, transient absorption spectroscopy studies in the microsecond time scale were carried out to investigate the dynamics of photogenerated electron-hole pairs in TiO2-rGO nanocomposites, prepared by a hydrothermal method, under different atmospheres: N2, O2, and N2 saturated in CH3OH. Under N2 atmosphere, the transient absorption signal detected in the region between 450 and […]

Phototransformations of 2-aminonicotinic acid resolved with matrix isolation infrared spectroscopy and ab initio calculations

The structure and phototransformations of 2-aminonicotinic acid (ANA) induced by tunable UV laser were studied in low-temperature argon matrices with the use of Fourier-transform infrared (FTIR) spectroscopy. After the deposition of the argon matrix, two amino isomers (ANA-1 and ANA-2) were detected, with populations of 96 % and 4 %, respectively. Electronic structure calculations confirm […]

Discovery of NLO Semiorganic (C5H6ON)+(H2PO4)−: Dipole Moment Modulation and Superior Synergy in Solar-Blind UV Region

We herein report a novel semiorganic NLO material, (C5H6ON)+(H2PO4)−, 4HPP, showing promising excellent properties in the important solar-blind UV region where LAP and its deuterated form DLAP are the only commercialized semiorganic materials. For the first time, the 4-hydroxypyridine (4HP+, (C5H6ON)+) cation is identified as NLO active and how to eliminate the dipole–dipole interaction to […]