指導教授：段維新臺灣大學：材料科學與工程學研究所莊繼凱Chuang, Chi-KaiChi-KaiChuang2014-11-262018-06-282014-11-262018-06-282014http://ntur.lib.ntu.edu.tw//handle/246246/262046螢光粉為現今製造白光發光二極體(W-LED)的重要原料。本研究使用噴霧熱裂解法製備螢光粉體，噴霧熱裂解完成的粉末在經過鍛燒之後，形成球狀次微米等級到微米等級的粉末。本研究使用矽酸鋅作為螢光粉的主體晶格，並使用錳作為螢光粉的活化劑，觀察不同的鍛燒溫度以及不同的錳摻量對螢光粉特性的影響，並解析發光特性以及結晶度，微結構，錳的摻雜量的關係。發光效率主要被結晶性以及粉末中是否有殘存的氧化鋅相有關，而錳的摻雜量則影響發光特性，像是 激發光的衰減時間，強度以及波長。除此之外，將製備完成的粉末和相同化學組成固態合成法合成的粉末比較，兩種製程製備出的螢光粉體發光效率接近。In order to apply light emitting diode (LED) for lighting, the phosphor for LED lighting is essential. In the present study, a spray pyrolysis method was developed to prepare phosphor particles. After calcining at elevated temperatures, spherical particles with size around submicron to micron are produced. The transition ion, manganese, is used as the activator. The characteristics of the particles with different Mn content after calcination at different temperature are determined. The relations between the luminescence property and crystallinity, phase, microstructure, Mn conent of the prepared particles are established. The luminescence efficiency shows strong connection with crystallinity and phase. The Mn content in the host lattice also affects the luminescence such as decay time, intensity, and wavelength. For comparison purpose, the particles was also prepared by solid state reaction and compared with the powder prepared by spray pyrolysis method . The particles prepared by these two methods show similar luminescence efficiency.Content Chapter 1 Introduction........................................................................................... - 1 - Chapter 2 Literature Survey.................................................................................. - 3 - 2-1 Application and basic concept of phosphors .......................................... - 3 - 2-2 Mechanism of Light Emission in Phosphors[9] ..................................... - 6 - 2-2-1 Florescence and phosphorescence................................................ - 6 - 2-2-2 Phosphorescence mechanism ....................................................... - 7 - 2-3 Zn2SiO4:Mn2+ Phosphors ....................................................................... - 10 - 2-4 Preparation Techniques for Zn2SiO4 Particles..................................... - 13 - 2-4-1 Solid state reaction[29]................................................................ - 13 - 2-4-2 Sol-gel methods[30] ..................................................................... - 14 - 2-4-3 Supercritical process[34] ............................................................ - 14 - 2-4-4 Hydrothermal and solvothermal techniques[31]...................... - 15 - 2-4-5 Spray pyrolysis method[10]........................................................ - 15 - 2-4-6 Flame spray pyrolysis[33]........................................................... - 17 - 2-5 Stage of phosphor Particle Formation by spray pyrolysis[35, 38] ..........20 2-5-1 Precursor...........................................................................................20 2-5-2 Atomization .......................................................................................20 2-5-3 Evaporation period ..........................................................................21 2-5-4 Droplet Coagulation .........................................................................22 2-5-5 Thermal decomposition and sintering............................................22 Chapter 3 Experimental Procedures ........................................................................25 3-1 Processing .....................................................................................................25 3-1-1 Spray pyrolysis .................................................................................25 3-1-1-1 Starting Materials .................................................................25 3-1-1-2 Spray pyrolysis procedures ..................................................25 3-1-1-3 Heat treatment ......................................................................27 3-1-2 Solid state reaction ...........................................................................27 3-1-2-1 Starting Materials .................................................................27 3-1-2-2 Solid state reaction procedures ............................................27 3-1-2-3 Heat treatment ......................................................................28 3-2 Characterization ..........................................................................................28 3-2-1 Phase identification ..........................................................................28 3-2-2 Microstructure observation.............................................................28 3-2-3 Luminescence observation...............................................................29 3-2-3-1 Photoluminescence (PL) .......................................................29 3-2-3-2 Analysis of C.I.E chromaticity Diagram.............................29 3-2-4 Transmission Electron Microscope (TEM) observation ...............29 3-2-5 Surface area analysis through BET technique ..............................30 Chapter 4 Results .......................................................................................................33 4-1 Zn2SiO4:Mn phosphor prepared by spray pyrolysis ................................33 4-1-1 Phosphorescence phenomenon........................................................33 4-1-2 Microstructure observation.............................................................34 4-1-3 TEM analysis ....................................................................................39 4-1-4 BET Surface area analysis...............................................................42 4-1-5 Element concentration .....................................................................43 4-1-6 Phase identification ..........................................................................48 4-1-7 Luminescence properties .................................................................54 4-2 Zn2SiO4:Mn phosphor with (Zn+Mn)/Si ratio= 1:1 in the precursor.....62 4-2-1 Microstructure observation.............................................................62 4-2-2 Phase identification ..........................................................................63 4-2-3 Composition analysis .......................................................................65 4-2-4 Luminescence properties .................................................................65 4-3 Zn2SiO4:Mn phosphor prepared by solid state reaction ..........................67 4-3-1 Microstructure observation.............................................................67 4-3-2 Phase identification ..........................................................................68 4-3-3 Composition analysis .......................................................................70 4-3-4 Luminescence properties .................................................................70 Chapter 5 Discussion .................................................................................................73 5-1 Phase identification......................................................................................73 5-1-1 The formation of the host lattice, Zn2SiO4 .....................................73 5-1-2 Phase evolution during calcination.................................................74 5-2 Effects of manganse in the host lattice.......................................................76 5-2-1 EDS analysis......................................................................................77 5-2-2 XRD analysis.....................................................................................77 5-2-3 Photoluminescence analysis.............................................................79 5-2-4 Decay time of the particles...............................................................80 5-2-5 CIE color space.................................................................................81 5-3 Microstructure analysis...............................................................................81 5-3-1 SEM analysis.....................................................................................81 5-3-2 TEM analysis ....................................................................................83 5-3-3 BET specific surface area ................................................................83 5-3-4 Effects of microstructure on luminescence behavior ....................84 5-4 General discussion .......................................................................................84 Chapter 6 Conclusions...............................................................................................88 References ...................................................................................................................905613109 bytesapplication/pdf論文公開時間：2014/07/16論文使用權限：同意有償授權(權利金給回饋本人)噴霧熱裂解法螢光粉白光發光二極體Zn2SiO4:Mn鍛燒發光效率thesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/262046/1/ntu-103-R01527043-1.pdf