Special Issue "Luminescent Materials"
QuicklinksA special issue of Materials (ISSN 1996-1944).
Deadline for manuscript submissions: closed (31 December 2009)
Special Issue Editor
Guest Editor
Prof. Dr. H.T. Hintzen
Materials and Devices for Sustainable Energy Technologies, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P.O. Box 513 (Helix Building, STW 3.42), 5600 MB Eindhoven, The Netherlands
E-Mail:
Published Papers
Special Issue Information
Dear Colleagues,
Luminescent materials are well known for a long time from traditional lighting and display applications, like cathode-ray (television) tubes, fluorescent lamps but also X-ray screens. Exploration of novel materials classes during the last years has enabled development of new applications, e.g. white LEDs, plasma display panels, bio-markers and solar cells. Recent progress and future prospects show that luminescent materials remain not only interesting from a scientific point of view but also relevant from an application point of view. For many years to come, scientific challenges as well as societal needs in this research field can be addressed by chemists, physicists and materials scientists. This special issue reviews the latest developments on these novel luminescent materials, their preparation, crystal chemistry, characterization and optical properties. The intention is to focus on the relationship between the luminescence properties on the one hand and the chemical composition and structure on the other. Contributions as review or original papers on basic research or applied technology of promising luminescent materials are welcomed.
Prof. Dr. H.T. Hintzen
Guest Editor
Submission
All papers should be submitted to materials@mdpi.org. To be published continuously until the deadline and papers will be listed together at the special website.
Submitted papers should not have been published previously, nor be under consideration for publication elsewhere. All papers are refereed through a peer-review process. A guide for authors is available on the Instructions for Authors page. Materials is an international peer-reviewed quarterly journal published by Molecular Diversity Preservation International. Review manuscripts: Before writing their manuscripts, potential authors of review articles should forward the title and a short abstract to materials@mdpi.org. We will then provide feedback on the suitability of the topic.
Open Access publication fees are 300 CHF per paper. English correction fees and/or formatting fees (250 CHF) will be added in certain cases (550 CHF per paper for those papers that require extensive additional formatting and/or English corrections).
Keywords
- luminescence
- down-conversion
- up-conversion
- quantum-cutting
- luminescent material
- phosphor
- quantum dot
- LED
- solar cell
- display
- bio-marker
Planned Papers
Feature Papers
Type of Paper: Article
Title: Light-emitting Diodes Converting Phosphors
Author: Ru-Shi Liu
Affiliation: Department of Chemistry, National Taiwan University, Taipei 106, Taiwan; E-Mail: rsliu@ntu.edu.tw
Abstract: White light-emitting diodes (WLEDs) have matched the emission efficiency of florescent lights and will rapidly spread as light source for homes and offices in the next 5 to 10 years. WLEDs provide a light element having a semiconductor light emitting layer (blue or UV LEDs) and photoluminescence phosphors. GaN-based highly efficient blue InGaN LEDs combined with phosphors can produce white light. These solid-state LED lamps have a number of advantages over conventional incandescent bulbs and halogen lamps, such as high efficiency to convert electrical energy into light, reliability and long operating lifetime (about 100,000 hours). For the purpose of development of high energy-efficient white light sources, we need to produce highly efficient new phosphors, which can absorb excitation energy from blue or UV LEDs and generate emissions. The criteria of choosing the best phosphors, for blue (380-450 nm) and UV (360-400 nm) LEDs, strongly depends on the absorption and emission of the phosphors. Moreover, the balance light between the light emission from blue LEDs and the yellow YAG:Ce,Gd phosphor is important to obtain white light with high color temperature. The phosphors with high efficiency which can be excited by UV LEDs are important to obtain the white light with high color rendering index. Here, we will review the status phosphors for LEDs and prospect the future development.
Regular Papers
Type of Paper: Review
Title: Fabrication Methods and Luminescent Properties of ZnO Based Light-Emitting Diodes
Author: Ching-Ting Lee
Affiliation: Institute of Microelectronics, Department of Electrical Engineering, National Cheng Kung University, Tainan, Taiwan
Abstract: Zinc oxide ZnO is a potential candidate material for optoelectronic application, especially for blue to ultraviolet light emitting devices, due to its fundamental advantages, such as direct wide band gap 3.37 eV, large exciton binding energy 60 meV, and high optical gain 320 cm−1 at room temperature. Their luminescent properties have been intensively investigated for samples, in the form of bulk, thin film, or nanostructure, prepared by various methods and doped with different impurities. We will review briefly the recent progress in this field first in the paper. Then a comprehensive summary of the researches on the ZnO preparation and its luminescent properties, carried out in our laboratory, will be presented, in which the involved samples include ZnO films and nanorods prepared with different methods and doped with n-type or p-type impurities. The preliminary results of ZnO based LEDs are also discussed.
Type of Paper: Review
Title: Rare Earth Doped Fluoride Nanoparticles
Authors: L.G. Jacobsohn, T.L. James, C.J. Kucera, K. Sprinkle, J. DiMaio, B. Kokuoz, B. Yazgan-Kukouz and J. Ballato
Affiliations: Center for Optical Materials Science and Engineering Technologies (COMSET) and the School of Materials Science and Engineering, Clemson University
Abstract: Metal halides are strategic materials in optical technologies finding application in lighting, optical amplification and lasing, and radiation detection industries. This paper reviews the synthesis and luminescent properties of metal halide nanoparticles, with particular focus on rare earth (RE) fluoride nanoparticles obtained by our team. Nanoparticles were produced by precipitation methods that were tuned to optimize the synthesis of a specific precipitant using nitrates as precursors. Nanoparticles were characterized by x-ray diffraction, energy dispersive x-ray spectroscopy, transmission electron microscopy-based techniques, including high resolution and Z-contrast imaging, and photoluminescence measurements, yielding information on their structure, chemical composition, morphology, and luminescent properties, respectively. In particular, we discuss our results on the investigation of a series of RE-doped alkali earth fluorides, MgF2, CaF2, SrF2, and BaF2, and of the RE-doped heavy metal fluorides PbF2 and LaF3. The synthesis of core-shell nanoparticles is also presented, including selectively RE-doped LaF3-on-LaF3 core/multi-shell nanoparticles, BaF2/SrF2, and LaF3/CaF2 systems.
Type of Paper: Review
Title: Luminescence from Zinc Oxide Nanostructures and Polymers and their Hybrid Devices
Author: Magnus Willander
Affiliation: Department of Science and Technology, Linköping University, SE-601 74 Norrköping, Sweden
Abstract: Zinc oxide is a strong luminescent material and the same is valid for several polymers. Both materials have their drawbacks and advantages but when combining them using its nanostructure forms many important applications are coming up as e.g. large area white lighting. In this paper we are discussing our latest results regarding the origin of red, green and blue emission centers from the two different materials.Then we finish by analyzing our results from the electroluminescence from the different light emitting diodes we fabricated.
Type of Paper: Review
Title: Luminescence in Sulfides: A Rich History... and a Bright Future?
Authors: P.F. Smet and D. Poelman
Affiliation: LumiLab, Department of Solid State Sciences, Ghent University, UGent, Belgium
Abstract: Sulfide-based materials have attracted a lot of attention for a wide range of luminescence applications. Upon doping with Ce3+ and Eu2+, the luminescence can be varied over the entire visible region by appropriately choosing the composition of the sulfide host. Main application areas are flat panel displays based on thin film electroluminescence and ZnS-based powder electroluminescence for backlights. Recently, sulfide materials have regained interest due to their ability (in contrast to oxide materials) to provide a broad band, Eu2+-based red emission for use as colour conversion material in white-light emitting diodes (LEDs). In this review, the specific advantages and disadvantages of sulfide materials over other phosphor hosts are discussed.
Type of Paper: Review
Title: Rare Earth Activated Nitride Phosphors – Synthesis, Luminescence and Applications
Authors: Rong-Jun Xie, Naoto Hirosaki, Yuanqiang Li, Takashi Takeda
Affiliations: Nitride Particle Group, Nano Ceramics Center, National Intitute for Materials Science (NIMS), Japan
Abstract: Nitridosilicates are structurely built up on 3-D SiN4 tetrhedral networks, forming a very interesting class of materials with high thermomechanical properties, hardness, and wide band gap. Traditionally, nitridosilicates are often used as structural materials such as abrasive particles, cutting tools, turbine blade, and etc. Recently, the luminescence of rare earth doped nitridosilicates has been extensively studied, and a novel family of luminescent materials has been demonstrated. This paper reviews the synthesis, luminescence and applications of nitridosilicate phosphors, with emphasis on rare earth nitrides in the system of M-Si-Al-O-N (M = Li, Ca, Sr, Ba, La) and their applications in white LEDs. These phosphors exhibit interesting luminescent properties, such as redshifted excitation and emission, small Stokes shift, small thermal quenching, and high converison efficiency, enabling them to use as down-converison luminescent materials in white LEDs with tunable color temperature and high color rendering index. The syntheis of nitridosilicate phosphors is also introduced in this article.
Type of Paper: Review
Title: Preparations and Characterizations of Luminescent Organic-Inorganic Perovskite Semiconductors
Authors: Sanjun Zhang 1, Antoine Al Choueiry 1, Gaëtan Lanty 1, Jean-Sébastien Lauret 1, Emmanuelle Deleporte 1,*, Pierre Audebert 2, Laurent Galmiche 2, Cédric Boissière 3
Affiliations: 1 Laboratoire de Photonique Quantique et Moléculaire de l’Ecole Normale Supérieure de Cachan, 61 avenue du Président Wilson, 94235 Cachan, France.
3 LCMC, UMR 7574, 4 place Jussieu, T54 E5 55-54, 75252 Paris cedex 05, France
Abstract: We report on the synthesis, structural and optical characterizations of some novel organic-inorganic hybrid perovskite semiconductors (R-NH3)PbX4 and (H3N-R-NH3)PbX4, where R is an organic group which has been varied systematically, and X is a halogen. These luminescent semiconductors have been prepared under different forms: thin layers and nanoparticles. The samples show a self-assembled nano-layered structure, having the electronic structure of multiquantum wells. We have studied the relationship between their crystallographic structure, analyzed from X-diffraction and Atomic Force Microscopy, and their optical properties, determined from absorption, photoluminescence, photo-stability, and photoluminescence excitation performed as a function of the temperature
Type of Paper: Review
Authors: Debasis Bera; Lei Qian, Paul H. Holloway
Affiliation: Department of Materials Science and Engineering, University of Florida, FL Gainesville
Abstract: Quantum dots, whose particle size is about 2 to 3 nm, have very unusual properties. Quantum states and confinement of their excitons may shift their absorption and emission energies. Such effects are important for tuning their luminescence stimulated by photons (photoluminescence-PL) or electrons (electroluminescence-EL). Therefore, processing-structure-properties-performance relationships are discussed. Various methods for synthesizing quantum dots are discussed, as well as their resulting properties. Decoupling of quantum effects on excitation and emission are described, along with the use of quantum dots as sensitizers in phosphors. Uses of quantum dots in biological imaging, electroluminescence device, solar cell and other optoelectronic applications are reviewed.
Type of Paper: Review
Title: Luminescent Colour Centres in Lithium Fluoride Thin Layers or Novel X-ray Imaging Detectors
Authors: Francesca Bonfigli and Rosa Maria Montereali
Affiliation: ENEA, Physics Technologies and New Materials Dep., C.R. Frascati, Via E. Fermi 45,
00044 Frascati (Rome), Italy; E-mail: montereali@frascati.enea.it
Abstract: Point defects in insulating materials are successfully used for radiation detectors. Among them, colour centres in lithium fluoride are well known for application in dosimeters and in light-emitting devices and lasers. Electronic defects are produced in LiF crystals and films by different kinds of radiations. Some of them are optically active, with broad absorption and emission bands in the visible spectral range. Novel thin-films imaging detectors for extreme ultraviolet, soft and hard (up to 10 keV) X-rays, based on photoluminescence from aggregate colour centres in LiF, are currently under development. Among the main peculiarities of these LiF-based detectors, there are an intrinsic very high spatial resolution, a large field of view and a wide dynamic range. Moreover, they are easy to handle, as insensitive to visible light and no development process is needed. After exposure to X-rays, the latent images stored in the LiF thin layers are read with advanced optical fluorescence microscopes. They allow great versatility, as they can be grown in the form of thin films on different substrates by well assessed physical deposition techniques. Here we will review their peculiarities and prospect the future development in photonics, biology and in material science.
Type of Paper: Review
Title: A Review on the Rare-Earth Doped Tellurium Oxide Glasses for Fibre Laser Applications
Affiliation: 1IMR, University of Leeds, UK;
Abstract: The review article focusses on the spectroscopic properties of rare-earth ions in heavy-metal oxide glasses, especially TeO2 based glasses for engineering fibre, thin film and bulk glass lasers. We will review the rare-earth emission from visible to mid-IR, spanning from 470 nm to 3000 nm by emphasizing the importance of spectroscopic processes, e.g. non-radiative, radiative, and energy transfer rates amongst occupied states in a lasing transitions. The review will, wherever possible, make comparisons with different hosts for individual optical transitions. Main rare-earth dopants, either present singly or in combination, will be Er3+, Tm3+,Yb3+,Ho3+, Sm3+, Nd3+, Dy3+ and Ce3+. The review will also focus briefly on fibre, thin-film and bulk glass fabrication by emphasizing the importance of impurities. Tellurium oxide is a conditional glass former. Compositions of tellurium oxide glasses are re-engineered to make stable glasses and slightly modified to design core and clad of the optical fibre. The effect of rare-earth compositions on absorption spectrum are discussed in detail. By comparison the Germanium oxide (GeO2) can form glass, but a unary composition manifests poor solubility for rare-earth ions, which is why we will also emphasize the importance of the modification of glass structure. The influence of different pumping schemes on optical transitions will be discussed in detail.
Title: Optical Properties of Rare-Earth Doped Germanate and Tellurite Glasses with Metallic Nanoparticles
Authors: Luciana R.P. Kassab1 and Cid B. de Araujo2
Affiliations: 1 Laboratório de Vidros e Datação, Faculdade de Tecnologia de São Paulo, CEETEPS/UNESP, 01124-060, São Paulo, SP, Brazil; E-Mail: kassablm@osite.com.br
2 Departamento de Física, Universidade Federal de Pernambuco, 50670-901, Recife, PE, Brazil
Abstract: The optical investigation of rare-earth ions (REI) doped vitreous materials has been attracting large attention. The basic research of luminescence properties is still very active and applications are common in lasers, sensors, and 3D full - color displays.
Among the vitreous systems already known heavy metal oxide glasses present physical properties that are important for photonic applications such as high linear and non-linear refractive index, broad transparency window extending from the visible to the infrared region, small cutoff phonon energy and large stability against devitrification. In particular germanate and tellurite glasses deserve special attention because they are excellent to incorporate REI and adequate for the nucleation of metallic nanoparticles (NPs) [1].
In this paper we review recent developments that demonstrate improved REI luminescence in germanate and tellurite glasses containing metallic NPs [2-5]. The nucleation of silver and gold NPs was obtained for different vitreous compositions that incorporate single REI and co-doped samples with two REI species. Using samples containing REI and metallic NPs with controlled filling fraction we obtained luminescence enhancement up to 1000% and increased luminescence extending from the blue to the near-infrared region. In all cases the presence of silver or gold particles are essential to improve the luminescence properties of the samples either due to energy transfer from the NPs to the REI or by influence of the large local field on the REI positioned in the vicinity of the NPs.
References: [1] Kassab, L.R.P.; de Araújo, C.B. In Photonics Research Developments; Nilsson, V.P., Edt.; Nova Science Publishers: New York, 2008. Chapter 13. Page 385, and references therein.
[2] Kassab, L.R.P.; Pinto, R,.A.; da Silva, D.M.; de Araújo, C.B. J. Appl. Phys. 2008, 104, 093531
[3] Kassab, L.R.P.; Pinto, R,.A.; da Silva, D.M.; de Assumpção, T.A.A.; Araújo, C.B. J. Appl. Phys. 2009, 105, 103505.
[4] Kassab, L.R.P.; da Silva, D.S.; Pinto, R.de A.; de Araújo, C.B. Appl. Phys. Lett., 2009, 94, 101912.
[5] Kassab, L.R.P.; Bomfim, F.A.; Martinelli, J.T.; Wetter, N.U.; Neto, J.J.; de Araújo, C.B. Appl. Phys. B 2009, 94, 239.
Type of Paper: Review
Title: Luminescent Properties, Solubility, Thermal Analysis and NMR Studies of Eu(III) Complexes with Two Different Phosphine Oxides and Their Applications
Author: Hiroki Iwanaga
Affiliation: Electron Device Laboratory, Corporate Research and Development Center, Toshiba Corporation 1, Komukai Toshiba-cho, Saiwai-ku, Kawasaki, 212-8582, Japan; E-Mail: hiroki.iwanaga@toshiba.co.jp
Abstract: Eu(III) complexes have been extensively investigated as luminescent compounds because they have pure color luminescence due to their sharp spectra, excellent photo-durability and specific properties of being colorless and transparent under visible light when dissolved in polymers or solvents. They have the potential for application in emission devices, security media, ornaments and dye lasers. However, there are two main important problems in Eu(III) complexes that must be solved to be applied to many devices. They are hard to be dissolved in many of the polymers and solvents at large concentrations because they have high molecular weight and polarity. The other is a low absorption coefficient due to their f-f transition. Increase of solubility and absorption coefficient expands their application fields and enlarges the performances of devices. Experimental results show that solubility and emission intensity of Eu(III) complexes were drastically improved by introducing two different phosphine oxide structures into one Eu(III) ion, and fluorinated media was the best one to realize the largest emission intensity of the Eu(III) complexes. The thermal properties of Eu(III) complexes are correlated to the solubility and NMR analysis explain the relationships between the coordinated conditions of them and luminescent intensity. Ultraviolet-light-excited light emitting diodes (LED) using our Eu(III) complexes as red luminescence materials have very high performances (20mA, 870 mlm, red). It was also found that white LEDs consists of blue LED chip, inorganic yellow phosphors and Eu(III) complexes can reproduce human more vividly than previous ones. On the other hand, colorless and transparent emission media including novel rare-earth complexes have excellent transparency and strong pure color emission and are useful for security systems.
Last update: 26 February 2010