Different Concentrations Of Eu3 Research Articles

Novel reddish-orange emitting BaBPO5:Eu3+ phosphor for n-UV warm white-LEDs: Synthesis and study of structural and spectroscopic investigations

A novel reddish-orange emitting 2Ba2-xO-B2O3-P2O5:xEu3+ (x= 0.04, 0.06, 0.08, 0.10, 0.12 and 0.14 mol%) phosphor with different concentrations of Eu3+ ions were synthesized through high temperature solid-state reaction technique. The crystal structure has been studied by X-ray diffraction technique for all the concentrations of Eu3+ ions. The morphology and elemental analysis of the optimal ∼0.1 mol% concentration was examined by the SEM-EDS images. The functional groups were analysed by the FTIR characterization technique. The thermal properties were studied by the TGA-DSC analysis. The energy band gap of all the samples were analysed by using UV–VIS DRS technique. The photoluminescence properties of BaBPO5:Eu3+ phosphor with different concentrations of Eu3+ ions were investigated at λem = 611 nm and λex = 394 nm. Variation in emission intensity with Eu3+ ion concentrations, phonon side bands, multi-phonon relaxation rate and energy transfer mechanisms were studied. The BaBPO5:Eu3+ phosphors exhibit characteristic emission peaks corresponding to 5D0 → 7FJ (J = 0, 1, 2, 3, 4) transitions of Eu3+ ions under n-UV excitation. Among all the transitions, 5D0 → 7F1 (593 nm) transition shows higher intensity and asymmetric ratio (R21) for all concentrations of Eu3+ ions were calculated. The lifetimes of 5D0 level of Eu3+ ions in BaBPO5: Eu3+ phosphor were calculated by using fluorescent decay curve analysis. The CIE color coordinates reveal, reddish-orange emission in the low CCT range. These findings imply that BaBPO5: 0.1Eu3+ phosphor is a promising candidate for solid-state lighting applications as well as phosphor-converted warm w-LEDs.

Preparation, structure and spectral properties of Eu3+-doped Lu2O3 scintillation ceramics

Lu2O3 scintillation ceramics doped with different concentrations of Eu3+ were prepared by SPS in a vacuum environment. The microstructural properties of the prepared ceramics were analyzed using XRD, SEM and EDS in details. Excited by the 395 nm, the Eu3+-doped samples display a prominent emission peak at 612 nm, corresponding to the transition 5D0→7F2. The PL spectra across various concentrations identified 3 at.% as the optimal doping concentration. The temperature-dependent PL spectra reveal the activation energy of approximately 0.266 eV for the 3 % Eu3+-doped Lu2O3 ceramic. Under 395 nm excitation, the lifetimes of xEu:Lu2O3 (x = 0.01, 0.03, 0.05 and 0.07) ceramics were fitted to be 1.07 ms, 1.02 ms, 0.99 ms and 0.92 ms, respectively. The XEL spectra of Eu3+-doped samples are consistent with their PL spectra, aligning well with the sensitivity range of the detector. These results demonstrate that Eu3+:Lu2O3 scintillation ceramics are ideal materials for scintillation detectors.

UV light-activated Eu/ZnO flower-like microsphere for detecting NO2 gas with high response

In this work, the ZnO microsphere is prepared by hydrothermal method and modified with different concentrations of Eu. The morphology of ZnO:Eu sample shows flower-like microspheres with many nanosheets. The gas performance of ZnO:Eu microsphere is investigated for detecting NO2. Compared with pure ZnO, the response of ZnO:2 % Eu sensor is increased by 8 times, and the optimal operating temperature of that is decreased to 130 °C. Especially, the gas sensing properties of ZnO:2 % Eu sensor is enhanced under UV excitation. The recovery time of ZnO:Eu sensor is reduced by 1200 s, and the response is increased by 3.6 times under UV excitation. The above results show an increase in sensor response due to doping Eu and UV excitation. At last, the possible gas mechanism of ZnO:Eu is discussed with and without UV excitation. This finding provides important guidance for UV-assisted sensors to enhance NO2 response.

A Comparative Study of SiO2:Tb3+@Gd2O3:Eu3+ and Its Inverted Tb3+-Eu3+ Core-Shell Phosphors.

How to effectively improve energy transfer efficiency and luminous intensity inspired us to synthesize a series of SiO2:x%Tb3+@Gd2O3:y%Eu3+ samples, study their luminescence properties and interfacial energy transfer (IET), and compare with SiO2:x%Eu3+@Gd2O3:y%Tb3+. The results show that SiO2:x%Tb3+@Gd2O3:y%Eu3+ can exhibit adjustable multicolor luminescence from red to green at different concentrations of Eu3+ and Tb3+ or under different excitation wavelengths, and there exists efficient IET from Tb3+ to Eu3+ in SiO2:x%Tb3+@Gd2O3:y%Eu3+ and SiO2:x%Eu3+@Gd2O3:y%Tb3+, which improves the energy transfer efficiency and luminous intensity. In addition, the luminescence properties are different between SiO2:3%Tb3+@Gd2O3:3%Eu3+ and SiO2:3%Eu3+@Gd2O3:3%Tb3+, and the energy transfer efficiency of Tb3+ → Eu3+ in SiO2:3%Tb3+@Gd2O3:3%Eu3+ is obviously higher than that in SiO2:3%Eu3+@Gd2O3:3%Tb3+. The present study not only developed a kind of multicolor luminescent phosphor but also offered an important new strategy for improving the energy transfer efficiency and luminescent intensity.

Dopant concentration dependence on optical and scintillation properties of Eu-doped Gd3Al2Ga3O12 single crystals

We have studied scintillation properties of Eu3+-doped Gd3Al2Ga3O12 single crystals. Gd3Al2Ga3O12 single crystals with different concentrations of Eu3+ (0.5%, 1.0%, 5.0%, 10.0%, and 15.0%) were grown using the floating-zone method. In photoluminescence (PL) and scintillation properties, the Eu-doped Gd3Al2Ga3O12 single crystals showed emission peaks and several millisecond decay times due to 4f–4f transitions of Eu3+ ions. Pulse height spectra of all the samples were investigated under γ-ray irradiation from 137Cs (662 keV). The 0.5%, 1.0%, 5.0%, and 10.0% Eu-doped samples showed full energy peaks. Among all the samples, the 5.0% Eu-doped Gd3Al2Ga3O12 single crystal showed the highest light yield of 36 000 photons MeV−1.

Energy transfer-based color tunability, thermal quenching, and quantum yield of Sm3+/Eu3+ codoped lithium zinc borophosphate glasses

Lithium zinc borophosphate (LZBP) glasses, imbedded with Sm3+, Eu3+, & Sm3+/Eu3+ ions in solely and combinedly were synthesized using melt-quenching technique, and their energy-transfer-dependent photoluminescence (PL)-related characteristics were explored. LZBP: 0.5 % Sm3+ and LZBP: 0.5 % Eu3+ glasses exhibited intense orange and red emissions under 404 and 394 nm excitation wavelengths, respectively. When the Sm3+/Eu3+ codoped glass systems were excited with Sm3+ excitation (404 nm), has lead to a noticeable drop in the emission intensity of Sm3+ peaks at 562 nm (4G5/2 → 6H5/2; yellow), 602 nm (4G5/2 → 6H7/2, orange), and 645 nm (4G5/2 → 6H9/2, red) whereas the emission intensity of Eu3+ peaks at 591 nm (5D0→7F1; orange) and 617 nm (5D0→7F2; red) has enhanced. At the same time, the decay lifetime of singly doped Sm3+ decreased from 1.54 to 0.91 ms, with codoping different concentrations of Eu3+ ions. The decrease in both PL intensity and lifetimes of Sm3+ in the presence of Eu3+ suggests an efficient energy transfer (ET) from Sm3+→Eu3+, which is facilitated by dipole-dipole interaction. The ET from Sm3+→Eu3+ achieved through the channels, Sm3+:4G5/2 + Eu3+:7F1 → Sm3+:6H7/2 + Eu3+:5D0 and Sm3+:4G5/2 + Eu3+:7F2 → Sm3+:6H5/2 + Eu3+:5D1. Furthermore, ET from Sm3+ to Eu3+ is supported by the spectral overlay between Sm3+ emission and Eu3+ absorption, ET parameters (η(Sm3+⟶Eu3+) = 40.91 % and P(Sm3+⟶Eu3+) = 1098.9 S-1). The shift in color coordinated from orange to red, with an increase in Eu3+ doping content in the codoped glasses at 404 nm excitation demonstrates the promising application of the Sm3+/Eu3+ codoped glass system in orange-red light-emitting diodes. LZBP: 0.5 Sm3+/1.0 Eu3+ codoped glass exhibited good thermal stability (Ea = 0.19 eV), depending on temperature-dependent PL properties. The quantum yield (η) for the LZBP glass containing 0.5 Sm3+/1.0 Eu3+ codoped ions is evaluated to be 44.6 %.

Investigations of thermoluminescence characteristics of SrAlBO4 :Eu3+ phosphors irradiated with gamma rays and carbon ion beam.

A series of SrAlBO4 :Eu phosphors doped with different concentrations of Eu (0.1, 0.3, 0.5, 0.7, 1.0mol%) was synthesized using a solid-state diffusion method, and their thermoluminescence (TL) properties were analyzed for gamma and carbon ion irradiation. The phase purity, morphological properties, vibrational features, and thermal stability of the prepared sample were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetric/differential thermal analyzer (TG/DTA) techniques, respectively. The TL properties of the proposed materials showed broad dosimetric bands, peaking at 202°C for 0.12 kGy gamma irradiation. The highest TL intensity was obtained for a 0.7mol% concentration of Eu ions under gamma irradiation. Furthermore, the glow curve of the proposed materials showed a broad emission band, centred at 148°C under carbon ion beam irradiation and exhibited the highest emission intensity for a 0.1mol% Eu concentration. In addition, the dosimetric trapping parameters of the prepared samples such as symmetry factor, order of kinetics, activation energy, and frequency factor, were analyzed using various methods such as Chen's peak shape method, initial growth method, and the Ilich method. The obtained results of the samples showed the potential for dosimetric application.

Thermoluminescence study of ϒ irradiated SrSO4 nanoparticles doped with Eu for feasible application in dosimetry

SrSO4 nanoparticles doped with different concentrations of Eu were synthesised by using co-precipitation method and annealed at 500 °C, 700 °C and 900 °C respectively. The prepared SrSO4:Eu nanophosphors shows highly crystalline orthorhombic structure with crystallite size of about 30 nm as observed from the X-ray diffraction (XRD) pattern. TEM (Transmission Electron Microscopy) analysis confirms the particle size to be around 40 nm for the synthesised nanophosphors. Energy Dispersive X-ray (EDX) spectrum showed the presence of only Eu dopant without any other impurity into the SrSO4 sample. The thermoluminescence (TL) glow curve of 1 Gy of gamma ray irradiated SrSO4:Eu measured at heating rates 1 K/s has a well-defined single peak at around 468 K. The TL kinetic parameters for the synthesised nanoparticles evaluated using initial rise method, peak shape method, Booth method and deconvolution method were all in agreement and found to be activation energy (E), order of kinetics (b) and frequency factors (s).

Thermoluminescence studies of zinc borate (ZnB2 O4 ) phosphor doped with rare earths for dosimetric aspects.

A series of ZnB2 O4 phosphors doped with different concentrations of Eu and Dy (0.05 0.1, 0.2, 0.5, 1.0mol%) and co-doped with Ce (1, 2, 5, 7, 10mol%) respectively was prepared via the solid-state reaction technique and the thermoluminescence (TL) behaviour of gamma ray-irradiated samples was studied. The synthesized samples were irradiated with γ-rays for the dose range 0.03-1.20 kGy. The TL intensity variations with dose, dopant concentration, and the effect of co-doping were studied. The TL response curves for ZnB2 O4 :Eu3+ and ZnB2 O4 :Dy3+ , ZnB2 O4 :Eu3 ,Ce3+ and ZnB2 O4 :Dy3+ ,Ce3+ phosphor were observed. It was revealed that ZnB2 O4 :Eu3+ showed a linear TL behaviour for the dose 0.03-1.20 kGy and ZnB2 O4 :Dy3+ showed linearity for the gamma dose range 0.03-0.10kGy. Furthermore, fading for all the samples was observed to be less than 10% for a storage period of 30 days. In addition to this, the trapping parameters, especially activation energies were evaluated using the Ilich method and the initial rise method. The activation energy values obtained from both methods were in complete agreement with each other.

Luminescence mechanism modeling in Eu3+ doped polymethyl methacrylate by microscopic and macroscopic approaches

In this work, red emission is obtained from polymethylmethacrylate (PMMA) doped with europium ions (Eu3+) under ultraviolet excitation. PMMA:Eu3+ samples are successfully synthesized by free radical polymerization and characterized by X-ray diffraction (DRX) and photoluminescence spectroscopy. DRX patterns show the amorphous nature of PMMA and the crystalline phase of Eu3+. Optical bands related to Eu3+ in the polymer composites are observed in excitation and emission spectra and are attributed to the corresponding electronic transitions. The interaction between Eu3+ ions is studied through the emission spectra of PMMA:Eu3+ samples with different Eu3+ concentrations under an excitation of 395 nm. Luminescent emission response is analyzed theoretically using rate equation models with macroscopic and microscopic approaches. The numerical solution of the model agrees with the experimental results. The rate equation model considers that the interaction between Eu3+ ions is driven by the direct energy migration (Eu3+ → Eu3+). The Förster distance and the ratio of the pumping rate and the radiative and nonradiative relaxation constant of the PMMA:Eu3+ system are calculated, and it is demonstrated that the energy transfer rate and the quantum efficiency for both approaches agree. The results allow to predict the luminescent behavior of the PMMA:Eu3+ system with different concentrations of Eu3+ ions, and the method described here can be applied to other similar systems.

Combustion synthesized novel SrAlBO4:Eu3+ phosphor: Structural, luminescence, and Judd-Ofelt analysis

A series of new phosphor SrAlBO4 doped by Eu³+ was synthesized by using very known Combustion method. The structural and optical properties explored using X-ray diffraction (XRD). The XRD pattern was matched well with the standard PDF card no. 1542236.The obtained phosphor had orthorhombic structure with space group Pccn (56). The image of Scanning electron microscope shows the external morphology of SrAlBO4 phosphor material, which revails the irregular morphology and the material showed the non uniform structure with agglomerates' size was size ranging in several micrometers. The confirmation of present element and their percentage also shown in the EDX image. The luminescence properties of rare earth activated SrAlBO4 phosphor were determined by measurement of excitation and emission spectra. The PL emission spectra of Eu3+ doped SrAlBO4 phosphor show characteristics bands at 590 nm & 614 nm which corresponds due to 5D0 →7F1 and 5D0 →7F2 transition of Eu3+ ions upon 395 nm excitation. The effect of different concentration of Eu3+ on luminescence emission intensity of SrAlBO4 phosphor was also studied. Further, concentration quenching is explained using Blasse's equation and Dexter's theory. Also, Judd-Ofelt analysis was performed on photoluminescence emission spectra. On investigation synthesized rare earth activated SrAlBO4 phosphor can be suitable for all lighting application devices.

Rapid synthesis of BaMoO4 :Eu3+ red phosphors using microwave irradiation.

This study synthesized BaMoO4:Eu3+ red phosphors using the microwave method. In addition, the phase composition, morphology, and luminescence properties of the red phosphors were characterized using X-ray diffraction, field-scanning electron microscopy, and photoluminescence spectroscopy. The results revealed that doping red phosphors with different concentrations of Eu3+ does not change the crystal structure of the matrix material. The BaMoO4 :Eu3+ phosphors exhibited micron-scale irregular polyhedra, which could be excited by ultraviolet light with a wavelength of 395 nm to induce red-light emission. The optimal dosage of Eu3+ was 0.08, and the chromaticity coordinates of BaMoO4 :0.08Eu3+ phosphors were (0.5869, 0.3099). White light-emitting diode (w-LED) devices manufactured by using a combination of BaMoO4 :0.08Eu3+ phosphor and commercially available phosphors exhibited good white-light emission under the excitation of an ultraviolet chip. The BaMoO4 :0.08Eu3+ red phosphors that rapidly synthesized under the microwave field are expected to be used in w-LED devices.

NaGdF4:Eu3+ nanocrystalline: an in-depth study of energy transfer processes and Judd-Ofelt analysis using the luminescence excitation spectrum.

NaGdF4 nanocrystalline doped with different concentrations of Eu3+ ions were synthesized using the precipitation method. The structure and morphology of the material were investigated through the measurements of the XRD patterns and SEM images, respectively. The optical properties of the NaGdF4:Eu3+ nanocrystalline were studied in the framework of the Judd-Ofelt theory in which the Ωλ parameters were calculated by two methods: the traditional method using the luminescence spectra and the self-referenced method using the luminescence excitation spectra. In NaGdF4:Eu3+ nanocrystalline, the Gd3+ ions in the lattice act as sensitizer centers for the luminescence of Eu3+ ions under excitation at 272 and 310 nm. The energy transfer process from Gd3+ to Eu3+ causes the emission enhancement of Eu3+ ions. Upon excitation by the characteristic wavelengths of Gd3+, the luminescence efficiency of the Eu3+ ions in NaGdF4:Eu3+ is affected by two mechanisms: the emission of Gd3+ ions and the trapping of excited energy by the Eu3+ ions. The energy transfer between Eu3+ ions was also discussed in detail. This process leads to the enhancement of the luminescence bands originating from the 5D0 level. The dominant interaction between the Eu3+ ions in the energy transfer process is the dipole-dipole mechanism, which is determined by fitting the decay curve of the 5D2 level to the Inokuti-Hirayama model.

Structural and luminescent properties and energy transfer from Tb3+ to Eu3+ in LaVO4:xTb3+/ yEu3+ phosphors

The structural and optical properties of Eu3+, Tb3+ doped and Eu3+/Tb3+ codoped LaVO4 a self-activated host have been studied in detail. The XRD patterns of phosphor samples show that the LaVO4 crystallizes in monoclinic phase with the P21/n space group. The average crystallite size is ∼ 60 nm which decreases on doping of Eu3+, Tb3+ ions. The SEM patterns show particles of nearly spherical shape whose average size (∼ 5.64 µm) decrease on doping. The UV-Vis absorption and FTIR spectra of the samples were also studied. The excitation spectra of Eu3+, Tb3+ doped and Eu3+/Tb3+ codoped LaVO4 samples show intense charge transfer band (CTB) at 323 nm due to [VO4]3- group of host material. Eu3+ doped /codoped phosphor samples, also show large number of sharp bands due to Eu3+ ion alongwith CTB. On the other hand, Tb3+ doped LaVO4 show broad band near 375 nm. Photoluminescence could be observed from 5D0, 5D1 to different levels of ground state (7FJ) in Eu3+ in which the 5D0-7F2 at 614 nm is very intense. Similarly, in case of Tb3+, bands could be observed from 5D4-7FJ in which the bands in green and blue at 543, 489 nm due to 5D4-5F5 and 5D4-7F6 transitions respectively are very intense. Thus, samples containing Eu3+/Tb3+ together emit blue, green and red colors on 323 nm excitation. The phosphor samples containing LaVO4:Tb3+/Eu3+ also show energy transfer from Tb3+ to Eu3+ ion on excitation with CTB wavelength. The energy transfer efficiency has also been calculated by considering the changes in emission intensity of 543 nm (5D4-7F5) band and the lifetime of 5D4 level of Tb3+ ion for different concentrations of Eu3+ and fixed concentration of Tb3+ ion in LaVO4:1Tb3+/yEu3+ phosphor samples. The interaction of two ions was found dipole-dipole.

A facile sol–gel synthesis and characterization of europium (Eu) doped β-Bi2Mo2O9 nanoparticles with remarkably enhanced photocatalytic activity for waste-water treatments

• The pure and Eu doped β-Bi 2 Mo 2 O 9 nanoparticles were synthesised via sol gel method using acid medium and water medium. • Single phase β - Bi 2 Mo 2 O 9 formation and porous natured self-assembly was confirmed with XRD, SEM and Raman. • Eu doped Bi 2 Mo 2 O 9 shows enhanced photocatalytic activity thereby degrading the Methylene blue completely when compared to pure sample. A facile sol-gel technique was employed to synthesize the nanoparticles of β-Bi 2 Mo 2 O 9 in acidic and water medium and Eu doped β-Bi 2 Mo 2 O 9 in acidic medium. The crystalline structure of the synthesized nanoparticles was characterized by powder X-ray Diffractometry, thereby confirming the monoclinic structure of pure β-Bi 2 Mo 2 O 9 and Eu-doped β-Bi 2 Mo 2 O 9 . Raman analysis was performed to verify the phase purity and to identify the vibrational modes of synthesized pure and doped molybdates. The surface morphology of synthesized particles was examined using scanning electron microscopy, which shows the formation of a honeycomb-like structure with numerous pores. UV-visible spectroscopy and XPS studied the optical properties of synthesized nanoparticles. The dye degradation process demonstrated the photocatalytic activity under visible light radiation in which Methylene blue acts as a model dye. The change in the absorbance of the dye with synthesized β-Bi 2 Mo 2 O 9 and Eu-doped β-Bi 2 Mo 2 O 9 with different concentrations of Eu 3+ was studied by a UV-Visible spectrophotometer. The results indicate that the water-based β-Bi 2 Mo 2 O 9 shows more dye degradation than acidic-based β-Bi 2 Mo 2 O 9 . The doping of Eu3+ increased the photocatalytic activity of acidic-based β-Bi 2 Mo 2 O 9 synthesis, and the efficiency increased with an increase in the doping percentage of Eu 3+ . The 10% Eu:Bi 2 Mo 2 O 9 completely degraded the Methylene Blue dye (100%) within a period of 4hours.

Correlation between structural and mechano-optical response of modified europium in magnesium borotellurite glass

The establishment of structural-properties relationships in glass containing modified rare earth in magnesium borotellurite (BTM) with manganese nanoparticles remains a challenge due to their structural complexity. This work investigates the glass properties (physical, thermal, mechanical and emission) by modifying the Eu3+ content in BTM environment and relates with its structural properties. Glass samples are prepared using melt quenching technique. Various measurements are carried out to unveil the effect of different concentration of Eu3+ in BTM glass environment. As a results, glass containing 1.0 mol % of Eu2O3 possesses significance enhancement in hardness and thermal stability and agrees well with Raman and FTIR spectral analysis. The prepared glass experienced changes in borate and tellurite network. The photoluminescence spectra (PL) revealed the lasing potency of Eu3+ in modified glass in the visible region is due to efficient emissions from 5D0 to several transition state 7F1,2,3,4, that is suitable for solid-state lasers.

Thermally stable red luminescence from Eu3+ -activated telluro zinc phosphate glass under near-ultraviolet light excitation for photonic applications.

Telluro zinc phosphate (TZP) glasses doped with different concentrations of Eu3+ ions were prepared and their physical, structural, and luminescence properties were studied in detail to reveal the utility of the as-prepared glass for white light-emitting diode (w-LED) applications. The broad hump in the diffraction pattern specified the amorphous behaviour of the TZP glass. The various vibrational shoulder linkages were characterized using the Fourier transform infrared (FT-IR) spectroscopy. The optical absorption spectrum was measured in the ultraviolet (UV)-visible (Vis) light region for the Eu3+ -doped TZP (TZPE) glass and the optical band gap was found to be 3.12 eV. Eu3+ -doped TZP glasses showed several emission peaks in the visible region including an intense red emission peak due to the 5 D0 →7 F2 transition under an excitation wavelength of λex = 393 nm, which was matched with the emitting wavelength of the near-UV LED chip. Commission Internationale de I'Eclairage (CIE)chromaticity coordinates were situated in the red region and nearly matched with the coordinates of the commercial red phosphor (Y2 O3 S:Eu3+ ). The decay profile of the TZPE50 glass exhibited a single exponential fit with a decay time ( of 1.76 ms. Temperature-dependent photoluminescence (TDPL) studies demonstratethat the as-prepared glass consist of excellent thermal stability. The detailed analysis and results confirmed that the red-emitting TZPE glasses were potential candidates for white-LED and other photonic applications.

Spectroscopic characteristics and optimization of (Gd3+/Eu3+) co-doped in alkal borate glasses for solid state lighting material

The physical, structural, and luminescence properties of lithium aluminum borate glasses as a function of Gd2O3 and Eu2O3 concentration were reported. The glasses composition of 25Li2O–5Al2O3-YGd2O3-(70-Y-Z)B2O3-ZEu2O3 system was successfully synthesized through a conventional melt-quenching technique. The various Gd2O3 concentration, 2.5 mol% is suitably added into the host composite, supporting by X-ray induced luminescence and photoluminescence analysis. The influence of the Eu2O3 concentration doped glasses system has been investigated in different concentrations of Eu3+ ions. It was found that the emission intensity increase with an increase of Eu2O3 concentration up to 3.0 mol% (luminescence quenching. The maximum intensity peaks were located at 614 nm (red emission), which was due to 5 D0→7 F2 transitions of Eu3+ ions. The decay profile is measured to prove the occurrence of maximum energy transfer efficiency (Eu3+-Eu3+) obtained is as high as 15.36% for their potential candidature in solid state device applications.

Photoluminescence Studies on LiNa5(PO4)2:Eu3+ Phosphor

In this paper, LiNa5(PO4)2:Eu3+, a new class of phosphor, was prepared with different concentrations of Eu3+ by solution combustion synthesis. This series of prepared materials were investigated by using various experimental techniques. X-ray diffraction confirmed a consistent orthorhombic phase and agreed with the standard JCPDF data. This phosphor exhibits intense d red emission peaks at ~612 nm corresponding to 5D0–7F2 transition upon 392 nm excitation. The color of the emitting light is red, and the calculated chromaticity coordinates are well placed in the red region. The results indicate that the present phosphors could be the potential candidates for the source of red color both in lasers and in light-emitting diodes.

Concentration effect on the luminescent and structural properties of YPO4: Eu3+

Different concentrations of Eu3+ doped YPO4 samples were prepared using the co-precipitation reaction. The prepared samples were characterized by using XRD, PL (Photoluminescence), and FTIR. The crystallite sizes of the samples are found to be in the range of 10–18 nm. Photoluminescence studies give information about the excitation and emission spectra of the synthesized samples. Among the different concentrations of Eu3+ doped samples, 5at.% doped sample gives the highest emission spectrum as compared to others. Two intense emission peaks were found at 593 nm and 618 nm. These peaks are due to 5D0 -7F1 (magnetic dipole transition) and 5D0 - 7F2 (electric dipole transition) transitions of Eu3+ respectively. The average lifetime of the synthesized samples is found to be 3.52 ms.