Structure–Optical Behavior Correlation, Optimized Photoluminescence, and DFT Calculation of La₇O₆(BO₃)(PO₄)₂:Sm³⁺ Micropowder for Solid State Lighting

Abstract

To promote the development of the solid state lighting and display industry, exploring excellent inorganic phosphors has always been a hot scientific and applied issue. Herein, we have constructed a series of Sm 3+activated La 7 O 6 (BO 3 )(PO 4 ) 2 (abbreviated as LBPO) phosphors by means of the short-time high-temperature solid phase synthesis process. The crystalline phase composition, micromorphology feature, ionic states of elements, and diffuse reflectance absorption performance were solved in detail. LBPO is suitable as phosphor host materials according to the investigation on electronic properties by density functional theory. The excitation and emission performance is significantly influenced by the crystalline structure of the LBPO host and doped Sm 3+ concentration. The optimized photoluminescence strategy is presented: upon the strongest near-ultraviolet (UV) excitation of 404 nm, LBPO:7% Sm 3+ displays intense orange-red visible luminescence with the dominant emission at 605 nm ( 4 G 5/2 → 6 H 7/2 of trivalent samarium). Its concentration quenching mechanism is the dipolar interaction. On the basis of the investigation of the detailed CIE chromaticity coordinate, color purity (CP), correlated color temperature (CCT), and internal quantum efficiency (IQE), we may use LBPO:Sm 3+ micropowder as an alternative ingredient for phosphor-converted near-UV-based warm white LEDs.

Pure and RE3+-Doped La7O6(VO4)3 (RE = Eu, Sm): Polymorphism Stability and Luminescence Properties of a New Oxyvanadate Matrix

“…It is observed upon excitation at both 322 and 404 nm. Our materials show a much faster concentration quenching compared to, for example, the work of Zhu et al, wherein a 7%Sm:La 7 O 6 (BO 3 )­(PO 4 ) 2 matrix had the highest emission intensity …”

“…Our materials show a much faster concentration quenching compared to, for example, the work of Zhu et al, wherein a 7%Sm:La 7 O 6 (BO 3 )-(PO 4 ) 2 matrix had the highest emission intensity. 33 Finally, the luminescence decay times were measured for the Sm 3+ compositions. The decay profiles for the 2%, 5%, and 10% samples are shown in Figures S13−S15.…”

Synthesis of broadband NIR garnet phosphor Ca4ZrGe3O12: Cr3+, Yb3+ for NIR pc-LED applications

“…3a, the CZGO is characterized by a direct band gap, and the band gap (E g ) is 3.50 eV, which is smaller than that of the experimental value due to the underestimated interaction between electrons arrived at by the GGA-PBE method. 29 Obviously, the CB is mainly constructed by the d orbital of Ca and Zr, yet the p orbital of O and Zr form the VB. Notably, there is a similar p orbital for Zr and O, suggesting that their p orbital is coupled.…”

Synthesis of Samarium-Based Metal Organic Compound Nanoparticles with Polychromatic-Photoluminescence for Bio-Tissue Fluorescence Imaging

“…Samarium-based compounds are interesting lanthanide emitters. They typically show orange/red fluorescence [6,7,8,9,10,11,12,13,14,15,16], which is just at the edge of the visible light and the beginning of the NIR light. Reports of Sm–based compounds showing luminescence other than orange/red are fairly rare in the literature [17,18,19].…”

“…The spectroscopic chemistry behind the luminescence of the compounds may be related to ligand-to-metal charge transfer [6,7,8,9,10,11,12,13,14,15,16,17,18,19]. In order to tailor the luminescence of the Sm compound, a special design can be made in the ligands, where the electron can transfer between Sm atoms and the ligands.…”