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Near-UV (NUV)-excitable blue-light-emitting Eu2+ ions-doped Ca-chabazite Ca1.9Al3.8Si8.2O24 phosphor was synthesized by facile urea-assisted combustion synthesis method. Prepared materials were characterized by X-ray diffraction (XRD) study, scanning Electron Microscopy (SEM), and photoluminescence (PL) spectroscopy. The Eu2+-doped Ca1.9Al3.8Si8.2O24 calcium aluminosilicate phosphor exhibited intense and broad emission in the blue region. CIE chromaticity coordinates were plotted and obtained values were compared with standard NTSC coordinates. Electron vibration interaction (EVI) parameters such as Huang Rhy’s factor (S) and effective phonon energy (ħω) were calculated to determine the strength of electron–phonon coupling. The prepared mineral-based blue-emitting Near-UV-excitable phosphor may prove to be a potential candidate as a blue component for the white light emitting diode (wLED).

We report here, the Ca9La(PO4)5(SiO4)F2:1 mol%Eu3+ phosphor via doping of chloride, molybdate, vanadate, sulfate, and tungstate ions that were synthesized by high-temperature solid-state reaction method. The phase formation was confirmed by X-ray diffraction (XRD) measurements. Morphological studies were performed using scanning electron microscopy. Photoluminescence and thermoluminescence properties of the synthesized phosphors were systematically studied. The PL excitation spectra of host material show peaks at 395 nm and 466 nm corresponding to 7F0 → 5L6 and 7F0 → 5D2 transitions of Eu3+, respectively. Further photoluminescence properties also studied after doping of molybdate, vanadate, sulfate, and tungstate ions in host material. When excited at 395 nm and 466 nm, PL emission spectra show emission band at around 595 nm and 616 nm, which attributes to 5D0 → 7F1 and 5D0 → 7F2 transitions, respectively. Further TL glow curves of all the synthesized phosphors were studied when exposed to γ-rays.

Because of the importance of inorganic phosphates in the solid-state lighting industry, KZnPO4doped with some transition metal dopant ions like Cu+and Ag+ions were prepared by low-cost co-precipitation method at room temperature followed by annealing at a high temperature around 6500C. The prepared phosphors were characterized by X-ray diffraction. In the case of a Photoluminescence study for KZnPO4doped with Cu+, the emission was observed at 425 nm, which corresponds to the emission of Cu+ion. In the case of Ag+doped KZnPO4, weak emission was observed at 420 nm, which is assigned to the emission of Ag+ions. CIE chromaticity coordinate of KZnPO4doped with Cu+and Ag+ions phosphor was also evaluated via using OSRAM SYLVANIA color calculator and colour purity of concentration was nearly 95% of Cu+and Ag+ions. The obtained outcomes revealed that the prepared phosphor shows potential application in the field of solid-state lighting.

The trivalent Eu3+ activated KMg4(PO4)3 phosphor has been successfully prepared via solid state diffusion technique. The phase formation and structural morphological studies carried out by XRD pattern and SEM analysis. The photoluminescence excitation spectra centred at 395 nm attributed to 7F0→5L6 energy transition levels. PL emission spectra centred at 593 nm and 613 nm corresponds to 5D0→7FJ( J=1,2) transitions of Eu3+ in the host respectively. The experimental results showed that Eu3+ singly doped KMg4(PO4)3 phosphor under UV excitation gives intense red emissions. The critical Eu3+ quenching concentration (QC) was determined to be 1.0 mol% along with excellent CIE coordinates of (0.6326, 0.3670). All the above results exhibits, the prepared phosphor is promising material as UV excitable red emitting phosphor for w-LED.

The phosphor converted w-LEDs gaincrucial attention in solid state lighting (SSL) for generation of illumination owing to their numerous meritorious advantages such as superior life time, excellent efficiency, compactness, reliability and power saving consumption as well as environmental friendly. The quality of w-LEDs in lighting and display is influence by host phosphorand the choice of activator. So greatlyattemptwere dedicated to developed inventiveuni-nucleiluminescent phosphor materials compose of chromatic stability, optimum CRI and low correlated color temperature. This review elaborate theintroduction ofEu3+rare earth activated red emitting phosphor assigned to 5D0→7FJ (J= 1,2,3,4) energy levelsand its fundamental merit for w-LEDs. This article represent the analyseofcombination of different types of Eu3+ activated luminescent materials by traditional and novel methods and its impact on photoluminescence for SSL.

Perovskites based LEDs (PeLEDs) have emerged as solid-state devices with sharp linewidths and economical as compared to the organic light-emitting diodes. Several factors contribute to limit the performances of the PeLED devices and hence this review systematically accounts for the main issues that PeLEDs face in their commercialization in light industries. Modification of the cation size via A-site substitution and substitutions at B- and X-sites have been dealt in detail and fine-tuning of electronic structure and optoelectronic properties due to the change in the crystal environment has also been emphasized. The dynamics of the photo-excited state, charge transport, electronic structure, non-radiative recombination, pin-hole formation, exciton confinement have been discussed in detail to improve the PeLED performance. The methods for post-synthesis transformation and low-cost solution-based fabrication have been discussed. We also address the novel studies on quasi-2D perovskites for high spectral stability and other passivating systems. The suggestions have been made for next-generation PeLEDs based on the search for novel emitter material, optimization of charge injection, and light extraction efficiencies. The efficiencies of PeLEDs can be boosted by employing various light-outcoupling techniques have also been demonstrated.