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The current study focuses on the synthesis and other detailed studies on CaBi2Nb2O9 (abbreviated CBNO) phosphor doped with Dy3+ ions. The aforementioned phosphors were prepared via a solid-state reaction procedure and a comprehensive analysis of the crystal structure, particle morphology, vibrational bands, luminous characteristics, decay and thermal stability of the phosphors was done. Phase identification of the synthesized material was carried out using X-ray diffraction (XRD) technique and the optical bandgap was determined using diffuse reflectance spectra (DRS). The morphological studies and particle size estimation of the phosphor material were conducted using a scanning electron microscope (SEM). Under 452 nm excitation, the photoluminescence (PL) spectra of Dy3+-doped CBNO phosphor exhibit three peaks at 482, 576, and 666 nm, which correspond to the transitions 4F9/2 → 6H15/2, 6H13/2, and 6H11/2. The electric dipole–dipole interaction was the main mechanism for concentration quenching for Dy3+ ions. The estimated CIE chromaticity coordinates for Dy3+ ion-doped CBNO phosphors fall in the white region. The temperature-dependent PL (TD-PL) findings reveals that CBNO phosphors have a considerably superior thermal stability. The results of these investigations suggest that the CBNO phosphors doped with Dy3+ ions exhibit promising properties that could be used for prospective w-LEDs and other optoelectronic device applications. [ABSTRACT FROM AUTHOR]

This research presents the outcomes of diverse morphological and photoluminescence (PL) studies performed on Bi3+ ion–doped Ba3MoTiO8 phosphors prepared via the conventional solid‐state reaction method. Phase assessment was carried out via the X‐ray diffraction (XRD) studies. Field emission scanning microscopy (FE‐SEM) and energy‐dispersive X‐ray analysis (EDAX) have been used to study the surface morphology anda elemental composition. Fourier transform infrared spectroscopy (FT‐IR) was used to study the character and vibrational frequencies of bonds in the phosphor lattice. Room‐temperature PL was performed under 275 and 386 nm excitations, displaying a broad band in the blue region corresponding to the 3P1 → 1S0 transition of Bi3+ ions. The Commission Internationale de L'Eclairage coordinates and correlated color temperature values show that the as‐prepared phosphors emit in the blue vicinity. The decay curves under both excitation wavelengths show a single exponential behavior. Temperature‐dependent PL studies confirmed the high thermal stability of the phosphor. We want to endorse these phosphors as a blue‐emitting component in white light‐emitting diodes (w‐LEDs) and solid‐state lighting (SSL) applications. [ABSTRACT FROM AUTHOR]

The combustion process has been successfully used to synthesize Ba3MoTiO8:Sm3+ and Ba3MoTiO8:Sm3+/Eu3+ co-doped phosphors for white light emitting diode (w-LED) applications. For the as-prepared phosphors, X-ray diffraction (XRD), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR), diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy techniques have been used to investigate phase confirmation, morphological analysis, and PL properties. The PL emission spectra of singly Sm3+ doped and Sm3+/Eu3+ co-doped phosphors recorded under 409 nm wavelength show intense emission in reddish–orange and red regions, respectively. For Sm3+–Eu3+ co-doped phosphors, the intensity of Sm3+ peaks show a decrease with an increase in Eu3+ ion concentration, demonstrating the energy transfer from Sm3+ to Eu3+ ions. Quadrupole–quadrupole interaction is the mechanism responsible for energy transfer from Sm3+ ions to Eu3+ ions according to Dexter's hypothesis as applied to the PL spectra. This result is in consonance with the results of PL decay curves recorded under 409 nm excitation. The Commission Internationale de I' Eclairage coordinates calculated for singly Sm3+ doped and Sm3+/Eu3+ co-doped phosphors show colour tunability from reddish–orange to pure red regions. All the results obtained finally revealed the utility of the titled phosphors as tunable red emitters needed to fabricate w-LEDs. [ABSTRACT FROM AUTHOR]

In this present work, Dysprosium (Dy3+) ions doped potassium zinc strontium borate (KZSB) glasses were synthesized via the melt-quench method. X-ray diffraction (XRD) study of the prepared glasses shows a broad hump and confirms the amorphous nature of the glasses. Various vibrational shoulders were seen in the Fourier transform infrared (FT-IR) spectrum. Thermo gravimetric analysis–differential scanning calorimetry (TGA–DSC) was carried out to check the thermal stability and corresponding weight loss behavior of the un-doped sample. Absorption spectra were recorded for un-doped as well as doped glasses in the UV–VIS–NIR region, and the corresponding optical band gap was calculated. The photoluminescence (PL) spectra of as-prepared Dy3+ doped KZSB glasses under 350 nm excitation show three peaks at 482, 575 and 665 nm corresponding to the transitions 4F9/2 → 6H15/2, 6H13/2 and 6H11/2. Commission Internationale de I'Eclairage (CIE) chromaticity coordinates calculated from the emission data lie in the white region. The photometric analysis of prepared glasses under UV lamp with 365 nm excitation also shows white emission. Temperature-dependent PL (TDPL) investigation demonstrates the superiority in thermal stability of the as-prepared glasses, with an activation energy of 0.232 eV estimated for 0.5 mol% (optimized concentration of rare earth ion) of Dy3+ ions. After analyzing the results of all studies, we propose to use these borate glasses doped with Dy3+ ions for white light-emitting diodes (w-LEDs) fabrication and other solid state lighting (SSL) applications. [ABSTRACT FROM AUTHOR]

In this research work, Dy3+ doped alkali zinc alumino borosilicate (AZABS) glasses have been prepared via melt quenching technique. A series of AZABS glasses of varying concentrations of dysprosium (Dy3+) (0.1–2.5 mol%) was prepared. It was found that under UV excitation, 0.5 mol% Dy3+ doped glass exhibited maximum luminescence intensity. Subsequent photoluminescence studies like emission/excitation spectra, temperature-dependent photoluminescence and decay kinetics were also performed. The value of direct bandgap as calculated from Tauc Plot for 0.5 mol% of Dy3+ ions doped AZABS glass is 2.85 eV. Yellow to blue ratio and colorimetry analysis have showed that the as-prepared glasses are capable of producing cool white light. Application of Dexter theory showed that the energy transfer mechanism between the dopant ions in the glass matrix was of dipole–dipole nature. It is proposed that these Dy3+ doped AZABS glasses can be used as prospective materials in optoelectronic device applications such as solid-state lighting and w-LEDs. [ABSTRACT FROM AUTHOR]

The lipid kinase phosphatidylinositol 4 kinase III alpha (PI4KIIIa/PI4KA) is a master regulator of the lipid composition and asymmetry of the plasma membrane. PI4KA exists primarily in a heterotrimeric complex with its regulatory proteins TTC7 and FAM126. Fundamental to PI4KA activity is its targeted recruitment to the plasma membrane by the lipidated proteins EFR3A and EFR3B. Here, we report a cryo-EM structure of the C-terminus of EFR3A bound to the PI4KA-TTC7B-FAM126A complex, with extensive validation using both hydrogen deuterium exchange mass spectrometry (HDX-MS), and mutational analysis. The EFR3A C-terminus undergoes a disorder-order transition upon binding to the PI4KA complex, with an unexpected direct interaction with both TTC7B and FAM126A. Complex disrupting mutations in TTC7B, FAM126A, and EFR3 decrease PI4KA recruitment to the plasma membrane. Multiple post-translational modifications and disease linked mutations map to this site, providing insight into how PI4KA membrane recruitment can be regulated and disrupted in human disease., Competing Interests: Competing Interests J.E.B. reports personal fees from Scorpion Therapeutics and Reactive therapeutics; and research contracts from Novartis and Calico Life Sciences.