In-air self-reduction synthesis and luminescence properties from Mg21 Ca4 Na4 (PO4 )18 :Eu2+ -Eu3+ excited using ultraviolet light

A series of Mg₂₁ Ca₄ Na₄ (PO₄ )₁₈ :Eu²⁺ -Eu³⁺ phosphors was successfully synthesized using a high-temperature solid-state method in an air atmosphere. The phase structures and luminescence properties of the samples were studied in detail. The phosphors exhibited strong visible light emission under different wavelengths of ultraviolet light excitation. By harmonizing the doping concentration of Eu³⁺ to adjust the relative luminescence intensity of Eu²⁺ and Eu³⁺ , a colourful emission of phosphors could be achieved. In addition, the colour coordinates of the International Commission on lighting indicated that Mg₂₁ Ca₄ Na₄ (PO)₁₈ :Eu²⁺ -Eu³⁺ could be considered as a potential blue, orange and red phosphor for white light-emitting diode applications.

Structural analysis and optical temperature sensing performance of Eu3+-doped Ba3In(PO4)3

Eu³⁺-Doped Ba₃In(PO₄)₃ was synthesized through a high-temperature solid-phase method.

Tunable luminescence evolution and energy transfer behavior of Na3Sc2(PO4)3:Ce3+/Tb3+/Eu3+ phosphors

A series of color-tunable emitting Na₃Sc₂(PO₄)₃:Ce³⁺/Tb³⁺/Eu³⁺ (NSPO) phosphors were prepared by a combination of hydrothermal synthesis and low temperature calcination. The phase structure, photoluminescence and energy transfer properties of the samples were studied in detail. The tunable colors were obtained by co-doping the Tb³⁺ ions into the NSPO:Ce³⁺ or NSPO:Eu³⁺ phosphors with varying concentrations. Under UV excitation, the energy transfers from Tb³⁺ to Eu³⁺ in the NSPO host occurred mainly via a dipole–dipole mechanism, and the critical distances of the ion pairs (R_c) was calculated to be 17.94 Å by the quenching concentration method. And that, the emission colors of the NSPO:Tb³⁺,Eu³⁺ phosphors could be adjusted from green through yellow to red because of the energy transfer from Tb³⁺ to Eu³⁺. Based on its good photoluminescence properties and abundant emission colors, the NSPO:Ce³⁺/Tb³⁺/Eu³⁺ phosphors might be promising as potential candidates for solid-state lighting and display fields.

A series of color-tunable emitting Na₃Sc₂(PO₄)₃:Ce³⁺/Tb³⁺/Eu³⁺ (NSPO) phosphors were prepared by a combination of hydrothermal synthesis and low temperature calcination.

Novel tantalum phosphate Na13Sr2Ta2(PO4)9: synthesis, crystal structure, DFT calculations and Dy3+-activated fluorescence performance

A new tantalum phosphate, tridecasodium distrontium ditantalum nonaphosphate, Na13Sr2Ta2(PO4)9, was prepared using the high-temperature flux method. The structure can be described as a three-dimensional open framework containing isolated [TaV2(PO4)9]17−units that are interlocked by Na and Sr ions. Band structure studies by the first-principles method revealed that Na13Sr2Ta2(PO4)9is an insulator with an indirect band gap of 4.78 eV, which makes it suitable as a luminescent host matrix. A series of solid solutions,i.e.Na13Sr2–xTa2(PO4)9:xDy3+(x= 0.01, 0.02, 0.04, 0.06, 0.08, 0.1, 0.12 and 0.14), were prepared and their photoluminescence properties studied. Under 350 nm light excitation, these emit two typical emissions of the Dy3+ion,i.e.the4F9/2→6H15/2transition centred at 476 nm and the4F9/2→6H13/2transition centred at 570 nm.

Syntheses, crystal structures and photoluminescence properties of two rare-earth molybdates CsLn(MoO4)2 (Ln=Eu, Tb)

Single crystals of two cesium rare-earth molybdates CsLn(MoO4)2 (Ln=Eu, Tb) have been prepared using the high temperature molten salt (flux) method. Single-crystal X-ray diffraction analyses reveal that they crystallize in the orthorhombic space group Pccm (No. 49) and features a 2D layer structure that is composed of [Ln(MoO4)2]∞ and [Cs]∞ layers. Under near-UV light excitation, emission spectrum of CsEu(MoO4)2 consists of several sharp lines due to the characteristic electronic transitions of Eu3+ ions, whereas CsTb(MoO4)2 exhibits characteristic green emission of Tb3+ ions.

A novel blue light pumped yellow-emitting phosphor RbZnPO4:Dy3+ with satisfactory color tuning and thermal properties for high-power warm white light emitting diodes

Novel yellow phosphor RbZnPO₄:Dy³⁺ with satisfactory color tuning and thermal properties for high-power white LEDs.