1st Edition

New Generation of Europium- and Terbium-Activated Phosphors From Syntheses to Applications

By Mihail Nazarov, Do Young Noh Copyright 2012
    466 Pages 263 B/W Illustrations
    by Jenny Stanford Publishing

    This book concentrates on the luminescence and structural properties of the new generation of europium and terbium activated phosphors, associated phenomena, and related topics, from basic principles to the most recent discoveries. It summarizes the present state of the art in this rapidly growing field. The authors describe recent developments in the areas of rare earth doped phosphors and of some new materials or well-known materials with improved properties that open up new possibilities. The areas of focus include X-ray phosphors, phosphors for light-emitting devices, emissive displays, and fluorescent lamps. The book comprises theoretical and experimental analysis of various properties of phosphors, research methods and preparation techniques, and some promising applications.

    1. Phosphors and Luminescence
    1.1 Luminescence Classification
    1.1.1 Types of Excitation
    1.1.2 Fluorescence and Phosphorescence
    1.2 Luminescence Terminology
    1.2.1 Quantum Numbers, Term Symbols and L-S Coupling
    1.2.2 Selection Rules
    1.3 Luminescent Materials
    1.3.1 The Past and Present of Phosphors
    1.3.2 Major Applications of Phosphors
    1.4 Rare Earth Activation
    1.4.1 Radiative and Non-radiative Transitions
    1.4.2 Peculiarities of Eu and Tb Activation
    2. Synthesis of Phoshors
    2.1 General Requirements of Phosphors
    2.2 Solid State Methods
    2.2.1 Solid State Reaction Preliminary powder preparation Firing and calcinations Post-treatment
    2.2.2 Microwave Synthesis Method
    2.3 Wet-Chemical Methods
    2.3.1 Co-Precipitation
    2.3.2 Sol–Gel Techniques
    2.3.3 Hydrothermal
    2.3.4 Solvothermal
    2.3.5 Colloidochemical
    2.3.6 Spray–Pyrolysis
    2.3.7 Combustion Method
    3.Phoshor Characterization
    3.1 Morphology Analysis with Scanning Electron
    3.1.1 Electron Beam Interaction with Solid Matter
    3.1.2 SEM Images of Phosphors in Back-Scattered
    3.2 Cathodoluminescence Characterization
    3.2.1 Monochromatic Cathodoluminescence
    3.2.2 Panchromatic or Color Cathodoluminescence
    3.2.3 Composite Cathodoluminescent and
    Back-Scattering Electron Contrast in SEM
    3.3 Microanalysis
    3.3.1 Electron Probe Micro-Analyzer
    3.3.2 Energy-Dispersive X-Ray Spectroscopy
    3.3.3 Wavelength-Dispersive X-Ray Spectroscopy
    3.3.4 Example of Microanalysis Application
    3.4 Particle Size Analysis
    3.4.1 Methods of Particle Analysis
    3.4.2 Laser Diffraction
    3.4.3 Cumulative and Density Distribution
    3.5 X-Ray Diffraction Measurements
    3.5.1 X-Ray Generation and Properties
    3.5.2 Lattice Planes and Bragg’s Law
    3.5.3 Powder Diffraction
    3.5.4 Example of XRD Application
    3.6 Spectroscopic Methods in Structural, Morphology
    and Luminescence Characterization
    3.6.Spectroscopy Classification
    3.6.2 Photoluminescence Spectroscopy Photoluminescence excitation
    spectroscopy Measurements in the vacuum-ultraviolet
    3.6.3 X-Ray Generated Luminescence
    3.6.4 Cathodoluminescence Spectroscopy
    3.6.5 Fourier Transform Infrared Spectroscopy
    3.6.6 Raman Spectroscopy
    3.6.7 Terahertz Spectroscopy
    3.7 Computational Materials Science
    3.7.1 Ab initio Calculations
    3.7.2 Monte Carlo Calculations
    3.7.3 Hartree–Fock Algorithm
    3.7.4 Density Functional Theory
    4. Phosphors for Different Applications
    4.1 Europium and Terbium Activated CaWO4
    4.1.1 Introductory Remarks
    4.1.2 Phosphor Preparation
    4.1.3 Luminescence of Eu3+ and Tb3+ Activated
    CaWO4 Phosphors
    4.1.4 Analysis of Optical Lines
    4.1.5 Polarization Selection Rules
    4.1.6 Ab initio Calculations
    4.1.7 Concluding Remarks
    4.2 RE3+ Activated Y(Ta,Nb)O4-Based Phosphors
    4.2.1 Introductory Remarks
    4.2.2 Self-Activated Y(Ta,Nb)O4 Phosphors
    4.2.3 Terbium Activated Y(Ta,Nb)O4 Phosphors Effect of flux materials of flux concentration Effect of terbium concentration Effect of niobium addition
    4.2.4 Europium Activated Y(Ta,Nb)O4 Phosphors Photoluminescence properties Crystalline structure Morphology and particle size Vibrational spectra
    4.2.5 Double Activated Y(Ta,Nb)O4:Eu3+,Tb3+ Sample preparation Particle morphology and sizes X-Ray diffraction measurement X-ray luminescent measurement X-ray diffraction characterization Cathodoluminescence VUV excitation X-ray luminescence characterization Luminescence mechanism in double
    activated Y(Ta,Nb)O4:Eu3+Tb3+
    4.2.6 Stark Levels and Selection Rules Stark levels and selection rules for the
    transitions in Tb3+ and Eu3+ (4f8 shell) Experimental measurements VUV excitation X-ray excitation Low-temperature PL measurements
    4.2.7 First-Principles Electronic Structure Calculations Samples preparation Densities of states calculations Experimental results DOS and luminescence
    4.2.8 Red Emission Properties of (Y,M)NbO4:Eu3+
    (M:Al,Ga) nUV excitation X-ray excitation
    4.2.9 Configurationally Coordinate Diagram and Energy Transfer Model
    Transfer Model
    4.2.10 Terahertz Spectroscopy in Study Y(Ta,Nb)O4-
    Based Phosphors
    4.2.11 Concluding Remarks
    4.3 Phosphors Based on Europium Doped Oxides and Oxysulfides
    4.3.1 Introductory Remarks
    4.3.2 Eu3+ Activated Y2O3 Synthesis of europium doped yttrium
    oxide phosphors Structural and luminescent
    4.3.3 Eu3+ Doped Y2O2–La2O2–Gd2O2 Synthesis of europium doped yttrium–
    gadolinium–lanthanum oxide phosphors Structural and luminescent
    4.3.4 Eu3+ Doped Y2O2S–La2O2S–Gd2O2S Synthesis of europium doped yttrium–gadolinium–lanthanum Oxysulfide Phosphorus Structural and luminescent
    4.3.5 Phosphors Based on YVO4:Eu3+ and (Y,Gd)VO4:Eu3+ Synthesis of (YX, Gd1-X)VO4:Eu3+ phosphor
    by co-precipitation and solid state
    reaction route Structural and luminescent
    4.3.6 Concluding Remarks
    4.4 Yttrium and Terbium Aluminate Phosphors
    Co-activated by Eu3+
    4.4.1 Introductory Remarks
    4.4.2 Physico-chemical Aspects Related with
    the Synthesis of YAG-Based Phosphors
    4.4.3 Luminescence Properties of Tb3Al5O12:Ce3+ Eu3+ Preparation of the phosphors Measurements Luminescence properties
    4.4.4 Luminescence Mechanism and Energy-Level
    4.4.5 Quantum Efficiency of YAG and TAG Phosphors
    4.5 Thiogallate Luminescent Materials
    4.5.1 Introductory Remarks
    4.5.2 Structural and Luminescent Properties of Calcium,
    Strontium, and Barium Thiogallates
    4.5.3 New Efficient Multiphase Green Phosphor
    [SrGa2S4 □□ MgGa2O4]:Eu2+
    4.5.4 Electron-Vibrational Interaction in 4f–5d
    Optical Transitions
    4.5.5 Concluding Remarks
    4.6 Multiexcited Phosphors for LED Application
    4.6.1 Introductory Remarks
    4.6.2 Requirements of Multiexcitation
    4.6.3 Double Excitation in UV LED
    4.6.4 Triple Excitation in UV LED
    4.6.5 Double Excitation in Blue LED
    4.6.6 LED with Scattering Layer and Reflecting Medium UV LED Blue LED
    4.6.7 Concluding Remarks
    4.7 Other Luminescent Materials
    4.7.1 Luminescent Properties of Ca-a-SiAION:Eu2+
    4.7.2 (Ca1-xSrx)(S1-ySey):Eu2+ Phosphors with Controlled
    4.7.3 Concluding Remarks
    Appendix I: The Luminescence Literature
    a. Phosphor Books
    b. Phosphor Reviews
    Appendix II: List of Main Abbreviations


    Mihail Nazarov, Do Young Noh