Anomalous D₀ → F₄ transition induced by alkali ion co-doping in Eu-activated K₇SrY₂(BO) borates: A Judd-Ofelt and photoluminescence analysis for pc-WLEDs.

In this study, red-emitting K₇SrY₂(BO):Eu phosphors were synthesized via high-temperature solid-state reaction. The effects of Li and Na co-doping on structural and photoluminescent properties were investigated. XRD and Rietveld refinement confirmed a phase-pure trigonal structure.

Judd-Ofelt analysis and photoluminescence behavior of Tb-activated KSrY(BO) phosphors modified with alkali co-dopants for solid-state lighting applications.

In this study, the structural and luminescent properties of alkali-modified KSrY(BO) phosphors activated with Tb ions were systematically investigated for solid-state lighting and photonic applications. A combination of X-ray diffraction (XRD) with Rietveld refinement, vibrational spectroscopy (FTIR and Raman), and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) confirmed that the trigonal R32 structure of the host lattice is retained upon doping and co-doping, with Tb ions preferentially occupying Y sites. Photoluminescence (PL) studies revealed intense green emission centered at 540 nm (D → F transition), with maximum intensity observed at 3 wt% Tb, beyond which concentration quenching occurred.

Modeling of thorium (IV) ions adsorption onto a novel adsorbent material silicon dioxide nano-balls using response surface methodology.

The silicon dioxide nano-balls (nano-SiO2) were prepared for the adsorption of thorium (IV) ions from aqueous solution. The synthesized silicon dioxide nano-balls were characterized by Scanning Electron Microscopy/Energy Dispersive X-ray, X-ray Diffraction, Fourier Transform Infrared and BET surface area measurement spectroscopy. The effects of pH, concentration, temperature and the solid-liquid ratio on the adsorption of thorium by nano-balls were optimized using central composite design of response surface methodology.

Removal of thorium (IV) ions from aqueous solution by a novel nanoporous ZnO: Isotherms, kinetic and thermodynamic studies.

The adsorption of thorium (IV) from aqueous solutions onto a novel nanoporous ZnO particles prepared by microwave assisted combustion was studied using batch methods under different experimental conditions. The effect of contact time, solution pH, initial concentration and temperature on adsorption process was studied. The ability of this material to remove Th (IV) from aqueous solution was characterises by Langmuir, Freunlinch and Temkin adsorption isotherms.