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1.
Y2O2S:Eu nano crystallines were prepared by a new ethanol assisted combustion synthesis method using sulfurcontained organic fuel in an ethanol-aqueous solution. The as-prepared nanocrystallines were characterized by X-ray diffraction, transmission electron microscope, photoluminescence spectra and X-ray luminescence spectra. It is shown that the assistant fuel ethanol has the effect of decreasing the water needed, simplifying the experiment procedure by dissolving rare earth nitrate and sulfur-contained organic fuel into an even solution, and prompting the formation of rare earth oxysulfide by igniting firstly during heating that leads to combustion decomposition reaction. Y2O2S : Eu nano crystallines with strong photoluminescence and X-ray luminescence are obtained using thioacetamide as organic fuel. Mixtures of Y2O3 : Eu and Y2O2S : Eu are acquired using thiourea as fuel, and the content of Y2O2S : Eu increases until reaches to about half of the Y2O3 : Eu with the increasing amount of thiourea. Y2O2SO4 : Eu emerges when S/Y = 6 and increases with increasing thiourea amount.  相似文献   

2.
Long lastingphosphorescence(LLP)isaproper tyofphosphorswithlongdecaytime,rangingfroma fewminutestotensofhours[1].Inrecentyears,LLP materialshavebeenwidelyusedinmanyfieldssuch asroadsigns,emergencylighting,graphicarts,inte riordecoration,automobileinstrument,andoptical datastorage[2~4].Buttodate,theprogressonred phosphorescenceisveryslow.TheredLLPmaterialbasedonsulfide(CaS∶Eu3+)hasnearly3hafterglow.However,itisex tremelysensitivetomoistureandthuschemicallyun stable[5].CaTiO3∶Pr3+,BaT…  相似文献   

3.
Longphosphorescencephosphorshaveattractedconsiderableattentioninrecenthalf century[1] becauseoftheirpotentialapplicationsinsuchfieldsaslumi nouspaint ,safetyindicatorinemergencycase ,etc[2~ 4 ] .Sincethediscoveryofalkali earthaluminatelonglastingphosphorsin 1996 [1] ,theyhavebeenstudiedextensivelyastheyhavebetterstabilityandlongerpersistenttimethanthesulfidephosphorswhichwerewidelyusedinmanycases .Uptonow ,poly crystallinephosphorsofblueCaAl2 O4 ∶ (Eu2 ,Nd3 ) ,greenSrAl2 O4 ∶(Eu2 ,…  相似文献   

4.
Gd2 O3isagoodhostmaterialforluminescenceandhasbeenstudiedwelltheseyears .Gd2 O3dopedwithrareearth (RE)ionsisanidealsystemforfunda mentalresearchsuchasenergytransfer[1] .Moreover ,Gd2 O3∶REhasextensiveuse .Especially ,asahighefficientred emissionluminescentmaterial ,cubicGd2 O3∶EuhasbeenwidelyusedinX rayscintillatormaterial ,highdefinitionprojectiontelevisions ,flatpaneldisplaysandphotoelectronicapparatus[2 ,3] .Inthepastcoupleofdecades ,therehasbeenadramaticgrowthofinterestinnanocrystal…  相似文献   

5.
Nano sizedmetalsandsemiconductorsplayim portantrolesinvariousareas.Inthelastdecade,they havebeenextensivelystudiedbecauseoftheirintrigu ingpropertiessuchaselectronic,optical,magnetic,mechanicalandcatalyticpropertieswhichdifferfrom thoseofbulkmaterials[1~…  相似文献   

6.
SynthesisofY_2O_2S:Eu~(3+)PhosphorbyMicrowaveThermalEffectandItsLuminescentPropertiesLiYuanying(李沅英);CaiShaohua(蔡少华);DaiDechan?..  相似文献   

7.
Nanometermaterialshaveattractedagreatdealofattentioninthelastdecadebecauseoftheirgreatpo tentialfornanotechnologicalapplicationsandforun derstandingsomefundamentalconceptsabouttherolesofdimensionalityandsizein ,forexample ,optical ,electrical ,andmechanicalproperties[1,2 ] .Differentshapes ,suchasparticles ,films ,wires ,andtubes ,havebeenfabricatedwithvarioustechniques[3~ 6 ] .Inparticular ,thenanotubesusuallypresentnovelproper tiesassociatingwiththeirsmalldimensions ,highanisotropy ,andintr…  相似文献   

8.
Nanoparticlesandnanoclustermaterialsareanewclassofadvancedmaterialsexhibit inguniquechemicalandphysicalpropertiescomparedtothoseoftheirbulkmaterials[1 ] .Y2 O3 :Euisanefficientred emissionphosphorwhichhasbeenusedinfluorescentlights (FL)andcathoderaytube (CRTs…  相似文献   

9.
Temperature Dependence of Red Long Afterglow from Y_2O_2S∶Eu, Ti, Mg  相似文献   

10.
The nanocrystals Er2O3 were prepared by using a combustion method with Schiff base as a chelating agent. The Er(Ⅲ) coordanation compound of Schiff base, obtained from erbium nitrate and retinal Schiff base, underwent a combustion process and voluminous ashes formed when calcimining the complex in air. Pure cubic Er2O3 nanocrystals with a diameter of 13nm were produced. The nanocrystals were homogeneous and rigid coacervation was not observed. The photoluminescence emission spectrum of the erbium (Ⅲ) oxide nanocrystals shows that it has a characteristic peak at 1.54μm, and some other shoulder peaks appear on both sides of the main peak.  相似文献   

11.
Cerium activatedyttriumaluminumgarnet Y3Al5O12(YAG∶Ce3+)isknownasanefficientphos phor,whichhasstrongyellowluminescencewhenex citedbybluephotons.Therefore,YAG∶Ceisideally suitedforluminescenceconversionofbluelightemit tingdiodes[1,2],andusedintheassemblingofwhite lightemittingdiode(wLED),sinceblueandyellow arecomplementarycolors.Suchdiodesarenowcom merciallyavailable[2].HighluminancewhiteLEDhas beenarousedattentionaroundworldduetoitslighting withnohydrargyrum,highefficiencyandlonglife.…  相似文献   

12.
Agrowinginterestandpromisingpotentialofhighpowersolidstatelasershavebeenshowninmanyhightechnicalengineeringfields.Insolidstatelasers,oneofthekeyopticalpartsisthepumpingcavitywhichreflectsthelamplighttolaseractivecrystalsource.Intermsofthisapplication,t…  相似文献   

13.
14.
Citric acid complexing sol-gel auto-combustion method was explored to synthesize superfine Sr2CeO4 phosphors using the inorganic salts Sr(NO3)2 and Ce(NO3)3 as raw materials together with citric acid (CA) as a chelating agent. TGDTA, XRD, SEM and photoluminescence spectra were used to investigate the formation process, microstructure and luminescent properties of the synthesized Sr2CeO4. The results show that the crystallization of Sr2CeO4 begins at about 800 ℃ and completes around 900 ℃ with an orthorhombic structure. When the calcination temperature is above 1000 ℃, Sr2CeO4 partly decomposes into SrCeO3. SEM studies show that the particles of Sr2CeO4 obtained at 900 ℃ are sphericallike shape and superfine with diameter below 100 nm. The excitation spectrum of the superfine Sr2CeO4 phosphors displays a broad band with two peaks around 290 and 350 nm respectively. The former peak is stronger than the latter one. This broad band is due to the charge transfer (CT) band of the Ce^4+ ion. Excited by a radiation of 290 nm, the superfine phosphors emit a strong blue-white fluorescence, and the emission spectrum shows a broad band with a peak around 470 nm, which can be assigned to the f→t1g transition of Ce^4+ . It is found that the emission intensity is affected by the calcination temperature.  相似文献   

15.
Y_2O_3∶Eu荧光粉的制备方法及性质研究进展   总被引:1,自引:0,他引:1  
本文报道了近年来人们用来制备 Y2 O3∶ Eu粉末的多种方法 (高温固相合成、微波热合成、溶胶 -凝胶技术、共沉淀法、燃烧法、喷雾干燥法、高分子凝胶包膜法 ) ,并对各种合成方法所得产品的粒径、激发与发射光谱以及粉末的发光亮度做了分析和比较 ,同时对各种方法的特点进行了归纳和总结  相似文献   

16.
Eu^3+-doped Gd2Mo3O9 was prepared by solid-state reaction method using Na2CO3 as flux and characterized by powder X-ray diffractometry. According to X-ray diffraction, this material belonged to a tetragonal system with space group I41/α. The effects of flux content and sintering temperature on the luminescent properties were investigated with the emission and excitation spectra. The results showed that flux content and sintering temperature had effects on the luminescent properties, the optimized flux content and the best temperature was 3 % and 800 ℃ respectively. The excitation and emission spectra also showed that this phosphor could be effectively excited by C-T band (280 nm), ultraviolet light 395 nm and blue light 465 nm. The wavelengths at 395 and 465 nm were nicely fitting in with the widely applied output wavelengths of ultraviolet or blue LED chips. Integrated emission intensity of Gd2Mo3O9 : Eu was twice higher than that of Y2O2S : Eu^3 + under 395 nm excitation. The Eu^3+ doped Gd2Mo309 phosphor may be a better candidate in solid-state lighting applications.  相似文献   

17.
阴极射线管(CRT)用Y_2O_2S∶Eu红粉的市场、生产和研究   总被引:1,自引:0,他引:1  
Y2O2S∶Eu是目前彩电和显示器中广泛使用的红色荧光粉,本文对近年来国内外对Y2O2S∶Eu红粉的市场需求和研究状况以及我国的生产状况进行了综述。  相似文献   

18.
Rareearthcomplexisanimportantkindoflumi nescencematerials ,muchattentionhasbeenpaidtotheexcellentluminescencecharacteristicsbasedontheirelectrictransitionbetweenthe 4fenergylevels[1,2 ] .Inrecentyearsmanyrareearthcomplexesthatchelatedwithorganiccompounds ,s…  相似文献   

19.
Color plasma display panels (PDPs) have attract-ed considerable interest in recent years as componentsof wall-mounted television sets that are large ,flat andthin .In PDPs ,tricolor phosphors are used to convertthe vacuum ultraviolet (VUV) radiation into …  相似文献   

20.
The high-surface area nano-CeO2 was prepared by Ce(NO3)3 by precipitation method, with surfactant cetyhrimethyl ammonium bromide (CTAB) as templating agent. The effects of the precipitating agents, reaction temperature, ageing time, and calcination temperature on the surface area, as well as the pore structure and the mean crystallite size of nano-CeO2 were studied. It was found that the reaction of Ce(NO3)3 with NaOH in the presence of CTAB at 90℃ for 12 h yieldsed a cerium oxide/surfaetant mixture, which after calcination at 400℃ resulted in high-surface area nano-CeO2. The mean crystallite size of CeO2 was approximately 6 nm, surface area was in excess of 200 m^2· g ^- 1, pore size was approximately 9 nm, and the pore distribution was concentrative. Moreover, the surface area can still reach 147 m^2·g^- 1 after calcination at 700 ℃, which showed the good thermal stability of the CeO2. The number of oxygen vacancies in the structure of CeO2 corresponded with the surface area of CeO2, and the high surface area was propitious to the formalion of oxygen vacancies.  相似文献   

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