首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
Dy^3+在(LaO)3BO3和(GdO)3BO3中的光致发光   总被引:1,自引:1,他引:0  
研究了Dy^3+在(LaO)3BO3和(GdO)3BO3中的光致发光;探讨了基质晶体结构、稀土离子RE^3+的电荷半径比(Z/r)和Dy^3+含量对(Dy^3+)发光强度及发光颜色的影响;分析了(GdO)3BO3中Bi^3+对Dy^3+发光的敏化作用及Dy^3+4F9/2→^6H13/2超灵敏跃迁发射的自身浓度猝灭机理。  相似文献   

2.
3.
以碳酸盐为沉淀剂,采用共沉淀法合成Ni1/3Co1/3Mn1/3CO3前驱体,再按照一定的锂配比将其烧结合成层状Li(Ni1/3Co1/3Mn1/3)O2。通过SEM及电性能测试仪等方法,研究了碳酸盐前驱体的合成条件,考察了碳酸盐前驱体的振实密度与合成时pH值、溶液浓度以及反应时间的关系。经过实验分析,在pH=8、溶液浓度C=2mol.L^-1、反应时间t=12-13h时,合成的碳酸盐前驱体Ni1/3Co1/3Mn1/3CO3振实密度达到最高值0.98g.cm^-3。  相似文献   

4.
Ca3La(BO3)3中Dy3+的光致发光   总被引:2,自引:0,他引:2  
研究了Ca3La(BO3)3基质中Dy^3 的发射光谱和激发光谱。结果表明,强的激发峰值为351nm、367nm和386nm;Dy^3 的488nm和578nm发射的最佳浓度均为xDy=0.03;Dy^3 发射的黄光和蓝光强度比(用Y/B表示)随Dy^3 浓度的增加而逐渐增大;Dy^3 的^4F9/2→^6H15/2、^6H13/2跃迁发射的浓度猝灭机理均为电偶极-电偶极相互作用;同时还探讨了Ce^3 对Dy^3 发光的敏化作用。  相似文献   

5.
张俊卿  李玉生  周洋 《稀土》2007,28(4):87-89
利用DTA研究了EuCl3-NdCl3二元系相图,该体系有一个同分熔化化合物2EuCl3·3NdCl3,该化合物在635℃熔化,其成分为NdCl3,含量为60.0%(摩尔分数,下同),体系的2个低共熔点分别为462℃(NdCl3含量为33.2%)和582℃(NdCl3含量为71.4%).  相似文献   

6.
Dy3 isanimportantactivator .Ithasbeenexten sivelyappliedinmanyluminescentmaterials .Inre centyears ,someresearchershavestudiedthespec trumcharacteristicsofluminescentmaterialsdopedDy3 [1~ 6 ] andhaveobtainedsomemeaningfulre sults .InordertodevelopnewfluorescentmaterialsanddiscussthephotoluminescentruleofDy3 inthecomplexborate ,thispaperstudiesthephotolumines centcharacteristicsofDy3 inBa3La(BO3) 3host ,anddiscussestheinfluenceofthecharge to radiusratio(z/r)ofrareearthionRE3 andthecon…  相似文献   

7.
研究了转速,球磨时间等球磨工艺对3Y2O3-5Al2O3机械合金化过程的影响。结果表明:在较低的转速下(250r/min),提供的球磨能量很低,只会细化粉体颗粒;提高转速(400r/min),会促使Y2O3发生晶型转变,由稳定的立方晶转变成非稳态的单斜晶;继续提高转速(500r/min),还会使混合粉体发生合成反应,生成YAlO3(YAP)。在转速为500r/min,球料比为20∶1的球磨条件下,3Y2O3-5Al2O3粉体发生固相反应的过程可分为两个阶段:第一阶段,Al2O3颗粒晶格畸变,快速细化;同时,高能球磨促使Y2O3发生了晶型转变。第二阶段,Y2O3晶型转变基本完成,并呈无定形化,Y2O3和Al2O3发生合成反应,生成YAlO3(YAP)。但在球磨条件下,难以合成Y3Al5O12(YAG)、Y4Al2O9(YAM)。  相似文献   

8.
Luminescent material Ba3Gd(BO3)3 doped with Eu3+ ion was prepared by high temperature solid-state method. The preparing conditions, luminescent properties, and particle morphology of Ba3Gd(BO3)3:Eu3 + phosphor were studied with X-ray diffraction (XRD), fluorescence spectroscopy, and scanning electron microscopy (SEM). The results obtained by XRD showed that pure phase of Ba3Gd(BO3)3 was obtained at 1000℃. Images from SEM displayed that the particles of Ba3Gd(BO3)3:Eu3+ phosphor had a spherical shape with an average diameter of about 200-400 nm. The luminescence spectra showed that Ba3Gd(BO3)3:Eu3+ phosphor was effectively excited by the near ultraviolet (UV) light (396 nm) and blue light (466 nm). The main emission peaks of Ba3Gd(BO3)3:Eu3+ phosphor were assigned to the supersensitive transition 5D0-7F2 (611 and 616 nm) of Eu3+ ion when samples were excited at 255 and 396 nm, respectively, and the luminescent intensity of Ba3Gd(BO3)3:Eu3+ at 611 and 616 nm reached to the maximum when the doped content of Eu3+ ion was 10mol.%. Therefore, this phosphor could be a promising red component for possible applications in the field of white LED.  相似文献   

9.
CaTiO_3∶Pr~(3 )的合成及发光性质   总被引:3,自引:0,他引:3  
报道了稀土离子Pr3+激活的CaTiO3发光材料的合成方法,CaTiO3∶Pr3+位于613nm发射与Pr3+离子1D23H4光谱发射相一致。讨论了不同合成条件对CaTiO3∶Pr3+发光性质的影响  相似文献   

10.
The photoluminescence(PL) properties of Ca4YO(BO3)3 doped with Bi3+,Dy3+,and Pr3+ ions were investigated.These compounds were prepared using a typical solid-state reaction.The excitation and emission spectra were measured using a spectrofluorometer.For Ca4YO(BO3)3:Bi3+,the excitation spectrum showed the bands at about 228,309,and 370 nm which correspond to the 1S0→1P1 transition and the 1S0→3P1 transition of Bi3+ ions.The emission band at 390 nm corresponded to the 3P1→1S0 transition of Bi3+ ions.For Ca4YO(BO3)3:Bi3+,Dy3+,energy transfer occurred from Bi3+ to Dy3+ somewhat.In Ca4YO(BO3)3:Bi3+,Dy3+,Pr3+,the excitation band at 367 nm was enhanced obviously due to the energy migration from Bi3+ to Pr3+,which converted efficiently the emission of semiconductor InGaN based light-emitting diode(LED).Therefore,the emission of Dy3+ ions was enhanced due to the energy migration from the process of Bi3+→Pr3+→Dy3+.It resulted in the good color rendering.  相似文献   

11.
研究掺杂BaTiO3来提高铬酸镧材料的电阻.通过对烧结时间、掺杂BaTiO3比例的研究,发现掺杂BaTiO3铬酸镧材料的电阻率随烧结时间的增大呈现下降趋势.掺杂质量比1%~2%的铬酸镧在烧结20h后,电阻率基本稳定,使铬酸镧材料电阻可调.  相似文献   

12.
利用溶液法制备CH_3NH_3PbI_3钙钛矿光吸收材料,并研究了不同温度对CH_3NH_3PbI_3钙钛矿材料晶体结构和性能的影响。采用X射线衍射仪、红外光谱仪、紫外可见吸收光谱对CH_3NH_3PbI_3钙钛矿材料进行表征。结果表明:温度变化影响材料的晶体结构和性能。当热处理温度为85℃时,CH_3NH_3PbI_3钙钛矿材料的结晶性和吸光度最优,平均晶粒尺寸为375?左右,且材料能级为1.62 eV。  相似文献   

13.
LaF3及LaF3(掺杂)固体电解质的特性及其应用   总被引:1,自引:0,他引:1  
对LaF3及LaF3(掺杂)作为固体电解质的导电能力和特性进行了分析。讨论了掺杂对LaF3导电性的影响。介绍了LaF3及LaF3(掺杂)单晶固体电解质在室温水溶液中氟离子选择电极、多晶固体电解质在高温熔体中镧传感器、以及各类气体传感器中的应用。  相似文献   

14.
The (60 - x)Bi2O3 - xGeO2-30B2O3-10ZnO (x = 5, 10, 20, 30 molar percent) glasses doped with Er^3+ and Er^3+/Yb^3+ were fabricated using the melting method. The thermal stability of the glasses was studied with their DTA curves. The results show that the difference between the glass transition temperature and the crystallization onset temperature increases with the increase of GeO2 content, indicating that the thermal stability of the glass has become better. The absorption spectra were recorded and the stimulated emission cross sections were calculated using the McCumber theory. The Ω2, O4, and Ω6 parameters,the transition probability, the radiative lifetime, and the fluorescence branch ratio of Er^3+ for optical transition were calculated from their absorption spectra in terms of reduced matrix U^(t)(λ = 2, 4, 6) character for optical transitions. The infrared emission of Er^3+ was measured upon excitation with 970 nm light and the full width at half-maximum (FWHM) was estimated from the emission spectra. The pumping efficiency and the intensity of the emission at the 1.54 μm band of Er^3+ were enhanced considerably by co-doping Yb^3+ .  相似文献   

15.
用溶胶—凝胶法 (Sol- gel法 )低温合成了 Y2 O3- Si O2 ∶ Eu3 ,Bi3 红色发光粉。 X射线实验研究发现 ,85 0℃时 ,样品晶体结构为 Y2 Si O5,属单斜晶系 (a=9.0 12 ,b=0 .979,c=6 .6 30 ) ,空间点群为 PI1 /C;SEM实验显示发光体为不规则片层结构 ;粒度分析表明 :发光体粒度分布均匀 ,平均粒度为 0 .79μm;T≥ 6 0 0℃时 ,发光体出现温度猝灭现象  相似文献   

16.
采用固相反应法合成了(La1-xPrx) 2/3Sr1/3CoO3 (x=0.2,0.4,0.6,0.8) 双稀土氧化物系列粉体,研究了(La0.6Pr0.4) 2/3Sr1/3CoO3的成相过程和电导性能.结果表明,在实验过程中首先出现了La2O(CO3)和La2SrOx相,而La2SrOx相在270℃~910℃的较大范围内一直存在,再经过两次吸热到910℃时出现了(La0.6Pr0.4) 2/3Sr1/3CoO3 晶相,当温度达到1000℃时,(La0.6Pr0.4) 2/3Sr1/3CoO3 成为主晶相,在1250℃下烧结2h后,样品已成单一钙钛矿结构(La0.6Pr0.4) 2/3Sr1/3CoO3相.(La1-xPrx)2/3Sr1/3CoO3(x=0.2,0.4,0.6,0.8)双稀土氧化物的电导率在700℃附近时出现最大值,其中(La0.8Pr0.2) 2/3Sr1/3CoO3的电导率在中温范围内最大,适合作为中温固体氧化物燃料电池阴极材料.  相似文献   

17.
BackgroundAbsorptionofTmCl3andTm(NO3)3MatricesinGraphiteFurnaceAtomicAbsorptionSpectrometryTangYouwen(汤又文),MoShengjun(莫胜均)(De...  相似文献   

18.
通过连续改变电导池常数法(CVCC),用自制的电导率测试装置研究KCl溶液与熔融KCl的电导率。实验证明连续改变电导池常数法能满足于一般的科学实验要求,自制的电导率测试装置能满足常温实验和高温实验的电导率测试要求。通过此装置测定了钾冰晶石在(Na3AlF6+K3AlF6)熔体中的含量为40%,AlF3在(Na3AlF6+K3AlF6+AlF3)混合熔体中的含量分别为0、20%、24%和30%的电导率,实验还讨论了AlF3含量对电导率的影响。  相似文献   

19.
Under the excitation of UV light and cathode ray,the dependence of the excitation and emission spectraand luminescent lifetime of Eu~(3+)and Bi~(3+)on composition and structure in LABO_3 and GdBO_3 has been stu-died.The results indicate that the emission spectra of Eu~(3+)in LaBO_3 with aragonite structure and in GdBO_3with YBO_3 structure are quite different.Under 254 nm excitation,Eu~(3+)emission is sensitized by Bi~(3+)inGdBO_3 matrix.In other case Eu~(3+)emission is quenched by Bi(3+).  相似文献   

20.
Optical Spectroscopy of Er~(3 ), Er~(3 )/Yb~(3 ) Co-doped Bi_2O_3-GeO_2-B_2O_3-ZnO Glasses  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号