摘要
随着平板显示器如场发射显示器和真空荧光显示器的发展,阴极发光材料的要求也越来越高。为了得到高亮度,高效率的荧光粉,基质材料的选择是比较重要的一个环节。氧化物荧光粉就因为其良好的热稳定性广泛受到关注。而镓酸盐由于具有更好的化学稳定性,较窄的禁带宽度,更适合用来作为荧光粉材料。本文通过溶胶—凝胶法和固相法分别合成了ZnGa_2O_4和SrGa_2O_4荧光粉。讨论了不同类型的激活剂(Eu,V,Mo,In,Y,Al),敏化剂,煅烧温度,保温时间和激活剂浓度对荧光粉发光性能的影响。利用X射线衍射(XRD)分析相结构和组成,荧光分光荧光计(PL)检测发光性能,TG-DTA分析反应过程,SEM观察了发光粉的形貌,实验结果表明:
(1)通过柠檬酸溶胶-凝胶法可合成出ZnGa_2O_4∶Eu荧光体,当Zn∶Ga为1∶4时,所得成品的最强发射峰位于613nm处,说明Eu~(3+)离子占据了非反演对称中心的位置,属于Eu~(3+)特征~5D_0→~7F_2跃迁,其对应于红色光谱。而通过添加不同的敏化剂,在ZnGa_2O_4∶R∶Eu(R∶Ba,Sr,In,Mo,V)中,能有效提高发光强度。
(2)采用固相法合成SrGa_2O_4荧光粉,XRD结果表明:SrGa_2O_4属单斜晶系,晶胞参数a=9.43(?),b=9.00(?),c=8.39(?),β=89.06°,属P2_1/n(No.14)空间群。光谱数据表明:SrGa_2O_4∶Eu~(3+)荧光粉的发射主峰在610nm,Eu~(3+)离子占据了非反演对称中心的位置。当Eu~(3+)离子浓度大于1mol%时,位于590,610nm附近的2个发射峰均出现劈裂现象,即有2个~5D_0→~7F_1(586,597nm)、2个~5D_0→~7F_2(609,615nm)发射峰,~7F_2劈裂出两个分支的强度比例随Eu~(3+)浓度的变化而变化。
(3)采用固相反应法合成了SrGa_2O_4∶Eu∶Gd,Gd作为Eu的敏化剂与Eu之间存在能量迁移,其最强发射峰位于613nm,属于Eu~(3+)离子的~5D_0→~7F_2跃迁,发光强度得到增强。
(4)固相法合成Zn_(0.5)Sr_(0.5)Ga_2O_4∶Eu荧光粉。Zn_(0.5)Sr_(0.5)Ga_2O_4∶0.02Eu的发光强度最佳。
The development of flat panel display devices such as field emission displays (FEDs) and vacuum fluorescent displays (VFDs) requires highly efficient cathodoluminescent materials. It is important for the bright and efficient phosphor to choose the group material. Oxide phosphor is noticed because of the excellent heat stability. Gallate have high chemical stability and narrow band-gap, so it fit to be used as phosphor. This paper reported the synthesis of phosphor ZnGa_2O_4 and ZnGa_2O_4 and discussed the influences of activator, sensitizer, calcined temperatures, duration, and concentrations of activator on luminescent properties. Phase compositions and luminescent properties of the phosphors were investigated and detected by using XRD and phosphor luminometer (PL). The reaction process is analyzed by the TG-DTA and the appearance of the phosphor is observed by SEM.
(1) ZnGa_2O_4:Eu phosphor is synthesized by the sol-gel process , which is completely reacted with ratio of Zn : Ga=l : 4.The main peak at 610 nm can be ascribed to ~5D_0→F of Eu~(3+) , corresponding to red light. Eu~(3+) ion occupies a site with lacking inversion symmetry in ZnGaO host lattice. It could be change the luminescent intensity by
(2) The Eu~(3+) doped SrGa_2O_4 phosphor was prepared with the conventional solid state reaction method. The phase composition was characterized by powder X-ray diffractometry. The result shows that the producing powder belongs to monoclinic crystal system with its lattice constants: a=9.43(?), b=9.00(?), c=8.39(?),β=89.06°, and with space group P21/ n (No. 14) . The excitation and emission spectra were measured. The main peak at 610nm can be ascribed to the electric dipole transition ~5D_0→~7F_2, which indicates that Eu~(3+) occupies a site lacking inversion symmetry. The peaks at 590nm and 610nm transition emission split to two peaks respectively, ~5D_0→~7F_1, (586, 597nm) and ~5D_0→~7F_2 (609, 615nm) due to the crystal-field in the conditions of concentration of Eu with more than 1%. The strength ratio of two parts for the splitting peak ~7F_2can be changed according to the concentration of Eu.
(3) The phosphor of SrGa_2O_4: Eu : Gd was prepared with the conventional solid-state reaction method. Gd is sensitizer of Eu, there is energy transform between Gd and Eu. The main peak at 613 nm can be ascribed to ~5D_0→~7F_2 of Eu~(3+) . The luminescent intensity is improved.
(4) The Zn_(0.5) Sr_(0.5) Ga_2O_4 : Eu prepared by solid-state method. The results of the experiment show that the produced powder is the mixture of ZnGa_2O_4 and SrGa_2O_4.
引文
[1]中国科学院吉林物理所和中国科学技术大学《固体发光》编写组编,固体发光[M],1,北京,中国科学院出版社,1976,4-15.
[2]徐叙珞,发光材料与显示技术【M】,3,北京:化学工业出版社,2003,3.10.
[3]肖志国,蓄光型发光材料及其制品【M】,2,北京:化学工业出版社,2002,1-20.
[4]李建宇,稀土发光材料及其应用【M】,1,北京:化学工业出版社,2003,3—15.
[5]丁清秀,刘洪楷译,无机发光材料[M】,1,北京:化学工业出版社,1980.
[6]盛卫坚,贾义霞,俞开新,童国通,黄敏,高建荣.邓勇荧光材料的工艺研究及进展[J】.化工时刊,2002,2:8-12.
[7]洪广言,高效稀土发光材料【J],功能材料,1991,22(2),100-107.
[8] Bhargave R N, Gallagher K, Hong x, Optical properties of manganes-doped nanocrystals of ZnS[J], Phys. Rev. Lett, 1994,72,416-419.
[9]肖林久,孙彦彬,邱关明,陈水杰,代少俊.纳米稀土发光材料的研究进展[J】,稀土,2002,23(4),46-49.
[10]孙家跃,杜海燕,胡文祥,固体发光材料【M】,1,北京:化学工业出版社,2003,l-9. 。
[11]郭连全,CaW04晶体振动谱的理论分析【J】,人工晶体学报,2002,21(1):71.74.
[12]晓晔,电化学法制各高效结晶发光CAW04膜【J】,电子材料快报,1995,9:9-11.
[13]朱慧,熊光楠,Eu~(2+)在磷酸谰中的发光及Ce~(3+)_Eu~(2+)能量传递【J],发光学报,2003,24(3):234-238.
[14] Curie D, Luminescence in Crystals[M], Eng. London, Methuen, 1963,221.
[15] Takeuchi H, Arakawa M, EPR study of Cr~(3+0, Li~+ centers in several perovskitefluorides[J], J. Phys. Soc. Japan, 1984,53(1), 376-380.
[16]杨子元,屈绍波,KCdF3晶体中Cr~(3+)-Li~+中心区域结构研究【J】,发光学报,2001,22(1):12—15.
[17]蒋大鹏,赵成久,侯风勤,刘学彦,范翊,张立功,褚明辉,申德振,范希武,白光发光二极管的制备技术及主要特性[J】,发光学报,.2003,24(4):385—389.
[18]何捍卫,周科朝,熊翔,红外.可见光的上转换材料研究进展【J】,中国稀土学报,2003,2l(2),123-124.
[19]贡长生,张克立,新型功能材料【M】,北京:化学工业出版社,2000,369-372.
[20] Wauters D, Poelman D. Effects of rapid thermal annealing on electron beam evaporated SrS:Ce thin film electroluminescent devices made in H_2S ambient[J]. Journal of Crystal Growth, 1999, 204(1-2): 97-107.
[21] Ohmi K, Fujimoto K, Tanaka S, Imporvement of crystallographic andelectrouhuminescent charaxcteristics of SrS:Ce thin film deveices by post-deposition annelaing in Ar-S atmosphere[J], J. Appl. Phys., 1995,78(1): 428-434.
[22] Morishita T, Matsuyama H, matsui M, Distribution of luminescent centers in electroluminescent SrS:Ce films prepared by post-annealing in H_2S [J], Applied Surface Science, 2000,157,61-66.
[23]邓朝勇,王永生,杨胜,无机薄膜电致发光研究进展[J],功能材料,2003,22(2): 133-135.
[24]曲崇,徐征,陈晓红,邓朝勇,于文革,杨胜,PPV固态类阴极射线发光动力学 的研究[J],发光学报,2002,23(2):l 83.1 85.
[25]李傅,顾镇南,林建华,YTa04:Gd,Eu体系光致发光中的能量传递[J],物理化 学学报,1 999,1 5(9):794-797.
[26]刘全生,张希艳,王晓春,卢利平,柏朝辉,米晓云,胡洁,田学雁,多彩长余 辉发光陶瓷的研究[J].中国陶瓷,2005,41(1):52-55.
[27]张希艳,柏朝晖,关欣王晓春,王伟忠,孙宏志,曹志峰,杜锦秀,郭瑜, SrAl_2O-4:Eu~(2+),Dy~(3+) 长余辉光致发光材料的固相反应法合成与特性[J]-稀有金属材 料与工程.2003,32(5):379-382.
[28]董红军,常树岚,刘波,Eu~(3+)、Tb~(3+)掺杂Zn486013光致发光材料的研究[J].液 晶显示.2005,31(2):108-110.
[29]袁曦明,田熙科,于江波,许永胜,共沉淀法制备长余辉发光材料 SrAl204:Eu2+,Dy3+的研究[J].材料开发与应用,2002,l 7(2):26-30.
[30]周传仓,卢忠远,戴亚堂,王兵,共沉淀法制备超细长余辉发光材料铝酸锶铕 镝的研究[J].稀有金属,2005,29(1):20-24.
[31]翟永清,张绍阳,姚子华,杨琳,栗志彬,李常娥,刘来福,碳酸氢铵共沉淀法 制备Gd_2O_3:Eu纳米晶及其性质研究[J].河北大学学报(自然科学版),2005,25(1): 43-47.
[32]缪春燕,李东平,罗昔贤,林广旭,刘剑雄,魏坤,燃烧法快速合成新型蓝色硅 酸盐长余辉材料[J],中国陶瓷,2003,39(6):27~29.
[33]杨应国,袁曦明,王永钱,胡小华,王红梅,张继红,纳米蓝粉CaAl204:Eu2+ 的制备与研究[J].液晶与显示,2005,20(3):220-224.
[34]彭绍琴,曾锦萍,李越湘,用溶胶一凝胶法制备Y2O_3-SiO_2:Tb~(3+)发光材料[J].稀 土,2005,26(2):76-78.
[35]袁曦明,许永胜,于江波,田熙科,溶胶.凝胶法制备长余辉发光材料 SrAl_2O_4:Eu2~,Dy~(3+)的研究[J].稀土,2002,(23):33-38.
[36]康明,谢克难,卢忠远,藤元成,戴亚堂,孙蓉,熊小利,许丕池,溶胶.凝胶法 制各纳米级ZnO:Eu,Li红色荧光材料[J].四川大学学报(工程科学版).2005,37(1):65-68.
[38] Kutty T R N, Jagannathan R, Rao R P. Luminescence of Eu2+ in strontiumaluminates prepared by the hydrothermal method[J]. Material Research Bulletin, 1990,25(11): 1355-1362.
[38] Kutty T R N, Jagannathan R, Rao R P. Luminescence of Ce3+-dopedaluminoborates[J]. M_3Al_6B_8O_(24)(M=Mg, Ca, Sr, Ba)[J]. Material Research Bulletin,1990,25(3): 343-348.
[39] Kutty T R N, Jagannathan R, Rao R P. Luminescence of Ce3+-sensitized andDy^-activated aluminoborates, M_3Al_6B_8O_(24)(M=Ca, Ba)[J] .Material Research Bulletin,1990,25(4): 485-493.
[40] Jagannathan R, Rao R P, Kutty T R N. Eu2+ luminescence in MAl_3BO_7aluminoborates(M=Ca, Sr, Ba)[J]. Material Research Bulletin, 1992,27(4): 459-466.
[4l]蔡少华,党华,李沅英,冯守华,水热法合成CaW04荧光体的研究[J].高等学校化学报,1998,19(5):691-693.
[42]赵春燕,朱连杰,冯守华,曹志成,徐如人,BaBeF4:Sm3’的温和水热合成与光谱性质研究[J].高等学校化学学报,1998,19(7):1023.1025.
[43]于亚勤,周誓红,张思远.La_(1-x)Pr_xP_5O_(14)晶体的研究[J]人工晶体学报,2002,31(6):529-532.
[44]李峻峰,邱克辉,赖雪飞,李群,燃烧法快速合成铝酸锶基质长余辉发光材料[J].硅酸盐学报,2004,32(12):1560-1562.
[45]王安平,孙彦彬,邱关明,燃烧法合成稀土纳米长余辉发光材料SrO·xAl_2O_3:Eu~(2+),Dy~(3+)[J].稀土.2005.26(1):19-22.
[46]张迈生,王立格,杨燕生.微波快速合成硫化锶铜铋磷光体及Bi3+对Cll+的敏化发光[J].功能材料与器件学报,2000,6(2):95.100.
[47]张迈生,李君君,严纯华.微波场下CaS:Eu2~的快速合成及荧光光谱特性[J].光谱学与光谱分析,2001,21(3):304-307.
[48]张迈生,臧李纳.Ce~(3+),Sb~(3+)供激活的亚超细磷光体的微波快速合成和发光特性[J]。稀有金属材料与工程,2002,31(1):69-72.
[49]宋春燕,刘应亮,张静娴,黄浪欢,袁定胜,容建华,石春山,雷炳富,微波法合成橙红色长余辉磷光粉Gd_2O_2S:Sm~(3+)[J].暨南大学学报,2003,24(5):93~96。
[50]秦宇星,徐明霞,张平,硼在Eu~(2+),Dy~(3+)共激活SrAl_2O_4发光材料中作用的研究进展.材料导报[J].2005,19:347-349.
[51]田少华,李志强,宋伟朋,cu*对ZnS:Cu电致发光材料光致发光光谱的影响[J].河北大学学报(自然科学版),2004,24(5):482-485.
[52]邹开顺,李岚,谭海曙,张晓松,余华,ZnS:Zn,Pb宽带蓝色发光和发光机制[J].发光学报.2003,24(4):403-406.
[53】武秀兰,任强,董温蝶,燃烧法合成SrAl204:Eu~(2+),Dy~(3+)发光材料及其性能研究【J】.中国陶瓷,2004,40(6):13-15.
【54】董国义,韦志仁,李志强,共激活剂Br~-,I~-对ZnS:Mn,Cu·X发光中心的影响[J]河北大学学报(自然科学版),2001,21(1):41-44.
[55】邓春林,邱克辉.Ce~(3+)和Tb~(3+)共激活的硫化物发光材料的合成及发光性质[J】.成都理工大学学报(自然科学版),2003,30(4):409-4 1 2.
[56] P. H. Holloway, S. Jones and T. Trottier et al. Advances in field emission display phosphors[C]. IVMC'98, in Eleventh International Vacuum Microelectronics Conference, the Grove Park Inn, Asheville, NC, USA: Institute of Electrical and Electronics Engineers, 1998: 49-50.
【57】于敏,林君,周永慧,柠檬酸.凝胶法合成ZnGa204:Mn2+/Eu3~及其发光性能的研究【J】,发光学报,2002,23(3):287-290.
[58] Kim J S, Park H L, Kim G C, Kim T W, Hwang Y H, Kim H K, Mho S I, Han S D,Luminescence enhancement of ZnGa_2Q_4:Mn~(2+) by Ge~(4+) and Li~+ doping[J]. Solid StateCommunications, 2003,126(9): 515-518.
[59] Philip D R , Jeffrey J P , Michael D P, Eu~(3+) and Cr~(3+) Doping for redcathodoluminescence in ZnGa_2O_4[J]. J. Mater. Res, 2001,16 (M5): 1429-1433.
[60] Kim J S , Kim J S , Park H L, Optical and structural properties of nanosizedZnGa_2O_4:Cr~(3+) phosphor[J]. Solid State Communications, 2004, 131(12): 735-738.
[61] Xu Z H , Li Y X, Liu Z F, Xiong Z, Low-temperature Synthesis of NanocrystallineZnGa_2O_4:Tb~(3+) Phosphors via Pechini Method[J]. Materials Science and Engineering,2004, Bl 10(3): 302-306.
[62] Glasser F P and Dent Glasser L S, Crystal chemistry of some AB_2O_4 compounds[J].J. Am. Ceram. Soc, 1963,46:377-380.
[63] Kobzareva V P, Kovba L M and Lopato L M, Equilibrium diagram of theSrO-Ga_2O_3 system[J]. Russ. J. Inorg. Chem, 1976,21(6): 903-904.
[64] Kobzareva V P, Kovba L M and Lopato L, Equilibrium diagram of the SrO-Ga_2O_3system[J]. Russ. J. Inorg. Chem, 1976,21(6): 903-904.
[65] Kahlenberg V, Fischer R X and Shaw C S J, Polymorphism of StrontiumMonogallate: The Framework Structures of SrGa_2O_4 and ABW Type SrGa2O4 [J].Journal of Solid State Chemistry, 2000,153(2): 294-300.magnetoplumbite compounds SrM_(12)O_(19)(M=Al, Fe, Ga). Journal of Solid StateChemistry, 1990, 87(1): 186-194.
[68] Kohlenberg V, Parise J B and Kristallogr Z, Sr_3Ga_4O_9 a strontium gallate with anew type of tetrahedral layer structure[J]. zeitschrift fur kristallographie, 2001, 216(4):210-214.
[69] Kahlenberg V, The Crystal Structures of the Strontium Gallates Sr_(10)Ga_6O_(19) andSr_3Ga_2O_6[J]. Journal of Solid State Chemistry, 2001,160(2): 421-429.
[70] Kitai A H , Xiao T and Liu G, Doped amorphous and crystalline gallium oxides,alkaline earth gallates and doped zinc germinate phosphors as electroluminescentmaterials[P]. Canada: WO 97/02721,23 January 1997.
[1] Kim J S, Park H L, Kim G C, Kim T W, Hwang Y H, Kim H K, Mho S I, Han S D, Luminescence enhancement of ZnGa_2CvMn~(2+) by Ge~(4+) and Li~+ doping[J]. Solid State Communications, 2003,126(9): 515-518.
[2] Hsu K H, Yang M R, Chen K S. A study of ZnGa_2O_4 phosphor prepared by the solid method [J]. Journal of Materials Science: Materials in Electronics, 1998,9: 283-288.
[3]刘素琴。李朝建,黄可龙,张学英,全玉.ZnGa204的制备及其光学性能【J】.应 用化学,2005,22(3):0300-0303.
[4] Xu Z H , Li Y X, Liu Z F, Xiong Z, Low-temperature Synthesis of Nanocrystalline ZnGa_2O_4:Tb~(3+) Phosphors via Pechini Method[J]. Materials Science and Engineering, 2004, Bl 10(3): 302-306.
【5】于敏,林君,周永慧.柠檬酸.凝胶法合成ZnGa_2O_4:Mn~(2+),Eu~(3+) 及其发光性能的 研究【J】.发光学报.2002,23(3):0287-0290.
[6] Hirano M . Hydrothermal synthesis and characterization of ZnGa_2O_4 spinel fine particles[J]. Journal of Materials Chemistry, 2000,10:469-472.
[7] Jeong I K , Park H L, Mho S I. Two self-activated optical centers of blue emission in zinc gallate[J]. Solid State Communications, 1998,105(3): 179-183.
[8] Kim Jong Su , Kwon Ae Kyung, Kim Jin Su, Park Hong Lee, Kim Gwang Chul, Han Sang do. Optical and structural properties of ZnGa_2O_4: Eu~(3+) nanophosphor by hydrothermal method[J]. Journal of Luminescence, 2007,122-123:851-854.
[1] Blasse G, Chemistry and physics of R-activated phosphors[J]. Handbook on the Physics and Chemistry of Rare Earths, 1979, 4: 237-274.
[2] 郭培民,北京大学博士后出站工作报告,北京,2003:104-105.
[3] 刘晃清,秦伟平和张继森,ZrO_2中Eu~(3+)的发光特性[J].光谱学与光谱分析,2005,25(1):19-22.
[4] 张思远,晶体中f6组态的荧光和点对称性[J],发光与显示,1983,3:18-23.
[5] 陈永虎,刘波,施朝淑,Zimmerer G,GdPO_4∶Eu~(3+)和GdBO_3∶Eu~(3+)中”Gd-Eu”间的能量传递,中国稀土学报,2005,23(4):429-433.