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Ho3+-doped YVO4 phosphors were successfully prepared via a sol–gel process in which citric acid was used as a chelating agent.

The article briefly reports the fundamental scientific principles and landmarks in the field of luminescence and further enlightens the importance of persistent phosphor that is now widely used in luminous paints. Its main focus is on phosphorescence that makes use of lanthanides that have gained paramount importance in various cross-sections of luminescent applications. Both inorganic and organic afterglow materials, synthesis and characterization along with skilled researchers' essential updates on emerging trends and efforts are elucidated at length. It exclusively reviews the red/green/blue organic/inorganic/hybrid phosphorescent materials and the latest advances in the development of novel long afterglow materials that can accelerate the green technology in the world of luminescence.

We synthesize different concentrations of Dy3+,Eu3+ doped and co-doped La(PO4) phosphors via the solid-state synthesis and test their photoluminescence and I–V characteristics for WLEDs and solar panels.

This work presents the optimized luminescence spectra for the Ce

Semiconductor assisted photocatalysis is one of the most efficient methods for the degradation of complex organic dyes. A major limiting factor of semiconductor assisted photocatalysis is the requirement of a continuous source of light to perform a redox reaction. One of the upcoming solutions is photon energy-storing long afterglow/persistent phosphors. They are an unusual kind of rechargeable, photon energy capturing/trapping phosphors that can trap charge carriers (electrons/holes) in their meta-stable energy levels, thereby resulting in persistent luminescence. Persistence luminescence from such materials can range from minutes to hours. The coupling of long afterglow phosphors (LAP) with the conventional semiconductor is a promising way to support the photocatalytic process even in dark. In addition, dissimilar band structures of LAPs and semiconductor results in formation of heterojunction which further suppresses the recombination of charge. Such an encouraging idea of LAP for round-the-clock working photocatalytic system is in its premature stage; which is required to be investigated fully. Thus, we present a state-of-art review on the potential materials for assisting round-the-clock photocatalysis, trapping-detrapping mechanism in LAP materials, fabrication strategies and their associated characterization tools. Review also covers LAP materials and their photocatalytic mechanism briefly.

Highly new efficient vanadate based phosphor B2BiMg2V3O12 (B= K & Na) material incapacitated through rare-earth Dysprosium (Dy) and it was characterized by high temperature solid-state synthesis. Equipped phosphor was established by X-ray diffraction method. In Photo-luminescence measurements shows that the prepared phosphors doped by Dy is excited by near UV ultraviolet light reaching after 300 nm to 380 nm efficiently acceptable to recognize the emission in visible spectrum (in the range 400 nm –570 nm. The highly efficient prepared phosphor doped with lanthanide doped with Dy phosphor likewise showed the exact emission point at 487 nm and 571 nm at the excitation point at 325 nm. Hence, these prepared phosphors can find numerous applications as green emitting phosphor in the field of solid-state lighting area.

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.

In this work, RE

A trivalent Dy

A BaY

In the present study, the thermoluminescence (TL) properties of an Eu

A Eu

[This corrects the article DOI: 10.1039/C6RA04913C.].

Retraction of ‘A study on the luminescence properties of gamma-ray-irradiated white light emitting Ca2Al2SiO7:Dy3+ phosphors fabricated using a combustion-assisted method’ by Geetanjali Tiwari et al., RSC Adv., 2016, 6, 49317–49327, https://doi.org/10.1039/C6RA04913C.

This paper focuses on an optical study of a Tb

In this paper, we have reported the photoluminescence (PL) properties of the Ba

Rare-earth ions play an important role in eco-friendly solid-state lighting for the lighting industry. In the present study we were interested in Eu

Dy

The sol-gel synthesized Eu3+, Dy3+ and Tb3+ doped LiMgBO3 was studied for its TL response. The phase purity of the sample is checked using powder XRD pattern. The TL studies were performed by irradiating samples with γ-ray from 60Co irradiation source in the dose range 10Gy to 1kGy. The samples have shown a linear dose response over the said range. The complex glow curves were analyzed using GCCD function given by Kitis taking general order kinetic into consideration. The activation energy and order of kinetics were calculated using the curve fitting method and frequency factors using Chen’s formula.

Eu3+ doped Y4Al2O9 phosphor were prepared by modified combustion route employing mixed (Urea+Glycine) fuel. XRD pattern indicates that the sample structure belongs to single phase monoclinic. The effect of dopant concentration on Photoluminecence properties were investigated. Under 249 nm excitation, the red emission are observed at 609 nm. The emission intensity of Y4Al2O9 :Eu3+ phosphor increases with concentration of Eu3+ ion from 0.5% to 2.5%. Further increase in dopant concentration shows decrease in emission intensity thereby exhibiting the phenomenon of concentration quenching.

Thermoluminescence (TL) dosimetry has emerged as an important technique for understanding the dynamics of electron trapping centers. TL glow–curve analysis methods have been applied to study the kinetics of trapped electrons and the activation energy of the corresponding\ electrons. Such methods include Chen’s Peak shape method, Initial Rise and Variable Heating Rate method. Although, the TL does prove the presence and the depth of electron trapping centres and it does not give direct information about the shallow electron trapping centres, Thermoluminescence dosimeters (TLD) are one of the most highly efficient means of characterization over a wide range of radiation doses. New materials are being introduced which allow more sensitivity and linearity in the radiation response of the TL signal output. Phosphors shows TL emission when it gets exposed to high ionizing radiation such as γ-rays, β-rays, C5+ (carbon-ion) beam etc. Energy gets stored in the material and this stored energy is emitted in the form of light when the material is heated. This phenomenon is used for measuring radiation dose. TL property of inorganic materials are decided by the factors such as crystal structure, band gap, synthesis process, crystal size, lattice imperfections and effects of impurities on solid. Lattice imperfections are described as defect centers that may occur when ions of either sign ions move away from their original sites thus leaving vacant sites that are able to interact with free charge carriers.

In this review paper, we discuss about photoluminescence emission of Gd3+ in various inorganic phosphors. Narrow band UVB (NB-UVB) emission of Gd 3+ in 312-315 nm is well sought after in medical field to treat photo-responsive diseases like atopic dermatitis, vitiligo, psoriasis, etc. However, this 4f-4f, 6Pj → 8S7/2 intra-configurational transition of Gd3+ is weak and hence needs to be sensitized. Suitable sensitizers like Bi3+, Pr3+ are found to enhance the PL emission of Gd3+. Such phosphors with sensitized Gd3+ emission is highly suitable for phototherapy lamps.

The growing need for leftover fuels and the ecological effects of their use was intended to give life to the traditionally extended global superpower infrastructure. Conventional, reliable fluorescent and incandescent lamps emit energy in the form of either heat or gas discharge. Both principles are strongly owing to the greater energy fluctuations that arise related to higher temperatures with the greater shifts of Stokes concerned. Within this work, we recorded sulphate-based blue & Orange-red emitting phosphors for lamp industry applications prepared using updated wet chemical synthesis methods, because the production of superb materials with high and stable fluorescent and luminescent properties is necessary to achieve high emission and fine clarity in the innovation of display systems. Morphological and structural tests and validation of phase and quality were conducted using XRD and SEM. The photoluminescent emission spectra of KSrPO4:Ce3+, Eu3+ phosphors show a blue emission band centered at 440 nm and a orange-red emission band centered at 593 nm and 618 nm. Typically, the structure of the Ce3+ ion in the ground state is split into two levels such as 2F5/2 and 2F7/2, while the5d1 excited configuration is divided by the crystal playing field into 2 and 5 elements.

An energy transfer process from Ce

We designed and synthesized a 2-(4-bromophenyl)-1-phenyl-1H-benzimidazole (pbi-Br) ligand, which was then employed to create an innovative phosphorescent cyclometallated iridium(III) (pbi-Br)

The present paper reports on the γ-ray and C

In the yttrium aluminium system, the YAlO3 phosphor is a prominent host because of the yttrium aluminium ratio (1:1). Phosphor was synthesized by the solid-state reaction method at variable concentrations of erbium (0.1-2.5 mol%). This method is suitable for large-scale production and is a less time-consuming method when compared with the soft synthesis method. The prepared sample was characterized by X-ray diffraction technique and the crystallite size was calculated by Scherer's formula. Vibrational and bending analysis of prepared phosphor for optimized concentration of erbium ion is described based on the Fourier transform infrared spectroscopic technique. The photoluminescence (PL) emission spectra of prepared phosphor for variable concentrations of erbium ion were recorded and the excitation spectrum was found to be at 291 nm with three shoulder peaks at 305, 270 and 242 nm. For 291 nm excitation, the emission spectrum was found at 546 nm and 552 nm. PL intensity increased with increasing concentrations of erbium and after 2 mol% emission intensity decreased due to concentration quenching. Spectrophotometric determination of YAlO3:Er(3+) is described by CIE co-ordinates and shows an intense emission in the green region such that the prepared phosphor can act as a single host for green light emission. Thermoluminescence glow curve analysis of the YAlO3:Er(3+) phosphor was recorded for different ultraviolet (UV) light exposures and gamma exposure. Different gamma doses 0.5-2 kGy show a linear response. Kinetic parameters were calculated by the peak shape method.

Eu(2+)-doped Ba3Si6O12N2 phosphors were prepared successfully via a modified solid-state diffusion method. The phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence measurements. These phosphors were effectively excited at 355 nm and an intense emission peaking in the range 480 nm to 525 nm in the blue region was observed. The optimized dopant concentration was determined to be 1 mol% of Eu(2+) ion. The colour coordinates for phosphor were found to be (0.196, 0.326) in the blue region. This phosphor may find application for near-ultraviolet (NUV) excited lamp phosphors. The thermoluminescence study shows the complex glow curve. Trapping parameters (activation energy and frequency factor) were calculated for individual deconvoluted peaks by Chen's peak shape method, the initial rise method and the whole glow peak method.

The subject of this work is the characterization of the photoluminescence properties of RE 3+ doped bromoapatite inorganic optoelectronic phosphor material. This paper reports the luminescence properties of RE

An attempt is made to design and develop a low cost, simple but efficient instrument to measure the decay time of luminescence in phosphors used in displays. The approach employed here is generally an embedded system designed around an intelligent microcontroller Atmega-16 of Atmale. The system is using a time domain technique of measurement and is further enhanced by developing necessary software for online-offline analysis.

Synthesis of volatile Eu(acac)3phen and Tb(acac)3phen complexes by solution technique were reported in this paper. The combination of Eu and Tb complexes, namely TbxEu(1-x)(acac)3phen (x=0.1,0.3,0.5,0.7,0.9) were also synthesized by maintaining stoichiometric ratio. Optical properties of these synthesized complexes were studied using photoluminescence technique. Eu(acac)3phen exhibits red intense emission at 612 nm with a sharp spectral bandwidth 5 nm when excited at a wavelength of 323nm, while Tb(acac)3 phen shows green emission at 547 nm when excited at 347nm. The emission spectra of TbxEu(1-x)(acac)3phen reveals that Tb0.7Eu0.3(acac)3 phen complex exhibits maximum intensity among all the stichiometrically doped complexes. When Tb0.7Eu0.3(acac)3 phen was molecularly doped in poly methyl Metacrylate (PMMA) to check its compatibility in polymers, enhancement in intensity was observed in these blended films, proving that these complexes can be used as emissive materials for fabricating OLEDs and displays by vacuum deposition as well as solution techniques. Copyright © 2014 VBRI press.

Eu 3+ , Dy 3+ activated SrCaAl2O5 phosphor were synthesized by the combustion method at 550°C. The prepared phosphor characterized by X-ray diffraction and photoluminescence measurements. The photoluminescence study of Eu 3+ doped phosphor shows that the intensity of electric dipole transition ( 5 D0→ 7 F2) at 615 nm dominates over that of magnetic dipole transition ( 5 D0→ 7 F1) at 596 nm under 395nm excitation. The PL emission spectrum of Dy 3+ ion at 350nm excitation gives an emission band at 484 nm (blue) and 575 nm (yellow). The optimum concentration of both the dopant having highest luminescence intensity is found to be 0.5 mole %. The obtained PL results indicated that prepared phosphor is suitable as near UV excited white light-emitting diodes. Copyright © 2013 VBRI press.

Phototherapy is a renowned treatment for curing skin diseases since ancient times. Phototherapeutic treatment for psoriasis and many other diseases require narrow band ultra violet-B (NB-UVB) light with peak intensity at 313nm to be exposed to the affected part of body. In this paper, we report combustion synthesis of NB-UVB -313nm emitting Ca

A series of MZr