Analysis of europium doped luminescent barium thioaluminate

Europium-doped barium thioaluminate sputtering target was synthesized by powder sintering method and thin film was deposited by radio frequency(RF) sputtering.X-ray diffractometer(XRD) pattern indicated that the main compound of the target was BaAl4S7.Oxygen was the main impurity which led to the formation of BaAl2O4.It was shown that both BaAl4S7 and BaAl2S4 were contained in the as-grown thin films and a 471.7 nm emission peak in the PL spectra appeared due to a combination of BaAl4S7:Eu2+ and BaAl2S4:Eu2+.In addition,the product of oxidation in the film was BaSO4 instead of BaAl2O4 and led to an emission peak at 415.2 nm in the PL spectra assigned to the f→f transition of Eu2+ in the BaSO4 host.     

Optical Properties of Blue-Emitting BaAl2S4∶Eu Thin-Films for Inorganic EL Display

The optical properties of blue emitting BaAl2S4:Eu thin-films were studied. The emission peak is around 470 nm, whose FWHM (full width at half maximum) is 35 nm. The dielectric constant is 3.03 from transmission spectrum, and the optical band gap is approximately 4.6 eV. It is found that the cubic phase and orthorhombic phase exist in fabricated thin-films. Furthermore, the energy band structure of BaAl2S4:Eu thin-films from X-ray photo-electron spectra (XPS) and the absorption spectra were analyzed.     

电感耦合等离子体原子发射光谱法间接测定地表水和地下水中硫酸根

建立了电感耦合等离子体原子发射光谱法间接测定地表水和地下水中硫酸根的方法。样品经盐酸(1+1)酸化,煮沸除去碳酸根、硫化物等干扰物质后,通过加入适量的钡标准溶液将溶液中的硫酸根沉淀,再用0.45 μm滤膜干抽滤,收集滤液。以Ba 233.527 nm作为分析线,采用电感耦合等离子体原子发射光谱法(ICP-AES)测定滤液中的钡量,通过用加入的钡总量减去滤液中的钡量,计算得到沉淀样品中硫酸根所消耗的钡量,从而再间接计算出样品中硫酸根的量。据此,实现了地下水和地表水中硫酸根的测定。实验表明:地表和地下水样中的钙、镁、铝、铁、钾、钠对测定的影响可忽略;50.00 mL水样中加入3.0 mL盐酸(1+1)酸化时对测定的影响可忽略。在选定的实验条件下,钡的质量浓度在1.00～50.00 μg/mL范围内与其对应的发射强度呈线性关系,校准曲线的线性相关系数r=0.999 9。实验方法用于地表水和地下水样品中硫酸根的测定,测定结果与离子色谱法、铬酸钡分光光度法和比浊法相吻合,相对标准偏差(RSD,n=7)小于2.0%。     

电感耦合等离子体原子发射光谱法测定硅锰锆孕育剂中铝钙钡锰锆

通过硝酸-氢氟酸-盐酸分解试样,高氯酸冒烟驱走硅和氟,最后用盐酸溶解盐类,选择Al 396.152 nm、Ca 315.887 nm、Ba 233.527 nm、Mn 257.610 nm、Zr 339.197 nm作为分析线,电感耦合等离子体原子发射光谱法(ICP-AES)测定硅锰锆孕育剂中铝、钙、钡、锰、锆。通过对试液分取稀释,降低和避免了铁离子共存体系中基体效应和光谱干扰对待测元素测定的影响。铝、钙、钡、锰、锆质量浓度在0.50~4.00μg/mL时与其发射强度呈线性,校准曲线的线性相关系数均大于0.999 9;方法中铝、钙、钡、锰、锆的检出限为0.60~1.1 μg/g。按照实验方法测定硅锰锆孕育剂中铝、钙、钡、锰、锆,结果的相对标准偏差(RSD,n=10)为1.6%~3.0%,并与其他方法测定结果基本一致。     

Synthesis of Long Afterglow Phosphors MAl2O4:Eu2+, Dy3+(M=Ca, Sr, Ba) by Microemulsion Method and Their Luminescent Properties

Long afterglow phosphors MAl2O4:Eu2 , Dy3 (M=Ca, Sr, Ba) were synthesized by microemulsion method, and their crystal structure and luminescent properties were compared and investigated. XRD patterns of samples indicate that phosphors CaAl2O4:Eu2 , Dy3 and SrAl2O4:Eu2 , Dy3 are with monoclinic crystal structure and phosphor BaAl2O4:Eu2 , Dy3 is with hexagonal crystal structure. The wide range of excitation spectrum of phosphors MAl2O4:Eu2 , Dy3 (M=Ca,Sr,Ba) indicates that the luminescent materials can be excited by light from ultraviolet ray to visible light and the maximum emission wavelength of phosphors MAl2O4:Eu2 , Dy3 (M=Ca, Sr, Ba) is found mainly at λem of 440 nm (M=Ca), 520 nm (M=Sr) and 496 nm (M=Ba) respectively, the corresponding colors of emission light are blue, green and cyna-green respectively. The afterglow decay tendency of phosphors can be summarized as three processes: initial rapid decay, intermediate transitional decay and very long slow decay. Afterglow decay curves coincide with formula I=At-n, and the sequence of afterglow intensity and time is Sr＞Ca＞Ba.     

电感耦合等离子体原子发射光谱法测定钒钛高炉渣中钡

冶炼钒钛磁铁矿时加入一种作为示踪剂的碳酸钡以标定出铁过程中铁水所夹带的高炉渣。为准确测定钡的含量,在试验的基础上,建立了用电感耦合等离子体原子发射光谱法(ICP-AES)测定钒钛高炉渣中钡含量的方法。以氢氟酸、盐酸、硝酸混合试剂消解样品,冒高氯酸烟驱赶残余氢氟酸等试剂,盐酸溶解盐类后直接采用ICP-AES测定钡的含量。系统考察了钒钛高炉渣复杂共存体系所导致的基体效应、光谱干扰、背景噪音等干扰因素的影响,优选了灵敏度适宜的钡分析谱线(Ba 230.424 nm、233.527 nm、413.066 nm、455.403 nm、493.409 nm)、检测积分与背景校正区域以及ICP光谱仪工作参数。试验结果表明,在分析线扫描窗口内,钒、钛、铁、钙、镁、铝等主要共存基体元素均不产生谱峰,并且与试剂空白信号基线重叠一致,表明钒钛高渣炉中基体组分对测定钡不产生基体效应、光谱干扰等影响,因此实验方法未采用基体匹配校正措施,直接以钡元素标准溶液绘制校准曲线。对于Ba 230.424 nm、233.527 nm、413.066 nm、455.403 nm、493.409 nm分析线,方法的测定下限在0.000 2%～0.001 0%范围,背景等效浓度在0.000 3%～0.000 5%范围,相对标准偏差(RSD)小于2.5%,加标回收率在93%～102%之间。方法适用于质量分数为0.005%～2.50%钡的测定。     

微波消解-电感耦合等离子体原子发射光谱法测定铁硅铝磁芯中铝和硅

使用盐酸-硝酸-氢氟酸并采用微波消解法处理样品,选择Al 308.215nm和Si212.412nm作为分析线,基体匹配法配制标准溶液系列绘制校准曲线,使用电感耦合等离子体原子发射光谱法(ICP-AES)测定铝和硅,从而建立了微波消解-电感耦合等离子体原子发射光谱法(ICP-AES)测定铁硅铝磁芯中铝和硅的方法。结果表明,铝和硅的质量分数分别为1.00%~9.00%和2.50%~12.50%时与其发射强度呈线性,线性相关系数均不小于0.999 4;方法中铝和硅的检出限分别为0.020%和0.021%(质量分数)。实验方法应用于铁硅铝磁芯样品中铝和硅的测定,结果的相对标准偏差(RSD,n=6)为1.4%~2.2%;将测定结果与滴定法(测定铝)和重量法(测定硅)的测定结果进行比对,二者相吻合。     

Luminescent properties of Eu³⁺-doped BaZrO₃ phosphor for UV white light emitting diode

A novel orange phosphor Eu3+ doped barium zirconate(BaZrO3) was synthesized by conventional solid state reaction method and its crystal structure and luminescent properties were investigated in this paper.The X-ray diffraction patterns(XRD) showed that simple BaZrO3 phase was obtained.Monitoring at 596 nm,the excitation spectrum consisted of a broad band and a series of narrow bands and the stronger excitation peaks located at 275 and 393 nm,respectively.The emission spectrum excited by 393 nm UV light was composed of four narrow bands.The strongest emission was located at 596 nm.The appropriate concentration of Eu3+ was 0.025(molar fraction) for the highest emission intensity at 596 nm.The H3BO3 and ammonium were added as flux and the results showed that 2 wt.% NH4F ions was the optimal flux for BaZrO3:Eu3+.     

Combustion synthesis of Ce~（3＋）, Eu~（3＋） and Dy~（3＋） activated NaCaPO_4 phosphors

The preparation of NaCaPO4 doped with rare earth (RE) ions Ce3+, Eu3+ and Dy3+ by combustion method was described. Under UV excitation (251 nm) of NaCaPO4:Ce3+ showsd emission (367 nm) in UV range. When NaCaPO4:Dy3+ phosphor was excited at 349 nm, the emission spectrum showed intense bands at 482 nm (blue) and 576 nm (yellow). In Eu activated NaCaPO4 phosphor, the emission spectrum showed a dominant peak at 594 nm (orange) while others were at 614 and 621 nm (red) when excited at 393 nm. The prepared phosph...     

电感耦合等离子体原子发射光谱法测定硅铁钡孕育剂中9种元素

采用硝酸和氢氟酸溶解样品,高氯酸冒烟驱尽硝酸-氢氟酸,盐酸溶解盐类,选择Ba 233.527nm、Fe 259.940nm、Ca 317.933nm、Mn 257.610nm、Cr 267.716nm、Al 394.401nm、Ni 231.604nm、Cu 327.396nm、P 178.284nm为分析线,使用电感耦合等离子体原子发射光谱法(ICP-AES)测定钡、铁、钙、锰、铬、铝、镍、铜、磷,从而建立了硅铁钡孕育剂中钡、铁、钙、锰、铬、铝、镍、铜、磷等9种元素的测定方法。各元素校准曲线的相关系数均大于0.9995;方法中各元素检出限为0.00006%~0.00069%。按照实验方法测定标准样品GSB03-1607-2003中钡、铁、钙、锰、铬、铝、镍、铜、磷,结果的相对标准偏差(RSD,n=11)为0.63%~3.4%。实验方法用于测定标准样品GSB03-1607-2003和YSB14607-2001中钡、铁、钙、锰、铬、铝、镍、铜、磷,测定值与认定值基本相符。     

Blue-green BaAl_2O_4：Eu~（2＋）,Dy~（3＋） phosphors synthesized via combustion synthesis method assisted by microwave irradiation

Blue-green luminescent BaAl2O4:Eu2+,Dy3+ phosphor powders were synthesized via combustion synthesis method assisted by microwave irradiation in air. The phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectrophotometer. The XRD results revealed that when the concentration of urea was over 3 times higher than theoretical quantities, a BaAl2O4 single hexagonal phase was obtained. The SEM results revealed that the surface of the BaAl2O4:Eu2+,Dy3+ pow...     

电感耦合等离子体原子发射光谱法测定铜阳极泥中钡

铜阳极泥物料成分复杂,钡含量变化较大,现无相关检测标准。实验提出了碱性熔剂熔融-电感耦合等离子体原子发射光谱法(ICP-AES)测定铜阳极泥中钡含量的分析方法。确定的方法如下:准确称取0.2g试样,与4g 碳酸钠-碳酸钾熔剂混合完全,加入0.5mL消电离剂(15g/L氯化铯溶液),在(700±20)℃熔融30min,冷却,浸取,过滤,弃去滤液,将沉淀物溶解,定容。采用Ba 233.527nm作为分析线,建立了电感耦合等离子体原子发射光谱法测定铜阳极泥中钡的方法。通过元素干扰试验,检测10mg钡量,控制相对误差不大于±1%时,下列量(mg)的离子不干扰测定:Pb(II)(400),Cu(II)(350),Sb(V)(50),Bi(III)、Te(VI)(30),Ni(II)(10)。Ba的质量浓度在0.50~25μg/mL范围内与发射强度呈良好的线性关系,相关系数为0.99999;方法检出限为6.0μg/g。将方法用于铜阳极泥实际样品中钡的测定,结果的相对标准偏差(RSD,n=5)小于0.5%,回收率为94%~102%。     

Luminescence properties of BaAl₁₂O₁₉:Tb,Ce and energy transfer between Ce³⁺,Tb³⁺

BaAl12O19:Tb,Ce phosphors were prepared by sol-gel technique,the crystalline structures of samples characterized by XRD,and the luminescence properties and energy transfer between Ce3+ and Tb3+ were investigated.The results indicated that the emission intensity and the excitation wavelength range of Tb3+ increased when Ce3+ was doped.It demonstrated that the Ce3+ added in the BaAl12O19:Tb could deliver energy to Tb3+,and Ce3+ was not luminous by itself.The relative emission intensity of Tb3+ at wavelength of 548 nm was the strongest by Tb3+/Ce3+ ratio of 2:1,when excited at 310 nm,which was the characteristic adsorption wavelength of Ce3+.     

Upconversion Luminescence Properties of Ho^3＋, Tm^3＋, Yb^3＋ Co-Doped Nanocrystal NaYF4 Synthesized by Hydrothermal Method

Nanocrystal of upconversion （UC） phosphor Ho^3＋, Tm^3＋ , and Yb^3＋ co-doped NaYF4 was prepared by the hydrothermal method in the presence of the complexing agent EDTA. Under 980 nm diode laser excitation, the impact of different concentrations of Ho^3＋ ion on the UC luminescence intensity was discussed. The law of luminescence intensity versus pump power shows that the 474 nm blue emission, 538 nm green emission, and 642 nm red emission are all due to the two-photon process, while the 450 nm blue emission is a three-photon process. The UC mechanism and processes were also analyzed. The sample was characterized by transmission electron microscopy （TEM） and X-ray diffraction （XRD）. The result shows that Ho^3＋ ,Tm^3＋ , and Yb^3＋ co-doped NaYF4 prepared by the hydrothermal method exhibits a hexagonal nanocrystal.     

Low Temperature Luminescence Properties of Tm3+ Doped Aluminate Phosphor

(Ba0.66Sr0.33)Mg0.8Al11.47O19:Tm0.013 (BSMA:Tm3 ) phosphor was synthesized by solid-state reactions. The sample was characterized by X-ray diffraction (XRD), scanning electronic microscope (SEM), vacuum ultraviolet (VUV) spectra, ultraviolet (UV) spectra and FT-IR spectrum. XRD pattern reveals that BSMA:Tm3 has the same structure as BaAl12O19 phase. SEM image illustrates that the phosphor has the hexagonal shape and deep slice structure. VUV and UV emission spectra at 20, 50 and 100 K show that the low temperature luminescence intensities become weak gradually with the increasing of the temperature under 147 and 254 nm excitation. The strong broadband peaks at around 357 and 397 nm and the peak at 516 nm under 147 nm excitation all correspond to the characteristic transitions of Tm3 ions. However, under UV (254 nm) excitation, the main peak becomes 530 nm which has very high line intensity, and the peaks at about 362 and 403 nm are very weak. The excitation spectrum at 20 K shows that there are three absorption peaks at around 153, 186 and 193 nm when 516 nm emission is monitored. The absorption peaks of [AlO4], [AlO6] and Al-O can be observed in FT-IR spectrum.     

Luminescent characteristics of Ba3Y2（BO3）4：Eu^3＋ phosphor for white LED

The Ba3Y2（BO3）4：Eu^3＋ phosphor was synthesized using a high temperature solid-state reaction method and the luminescent characteristics were investigated. The emission spectrum exhibited one strong red emission at 613 nm, corresponding to the electric dipole 5D0-TF2 transition of Eu^3＋, under 365 nm excitation. The excitation spectrum of 613 nm indicated that the Ba3Y2（BO3）n：Eu^3＋ phosphor was effectively excited by ultraviolet （UV） （254, 365 and 400 nm） and blue （470 nm） light. The effect of Eu^3＋ concentration on the 613 nm emission of the Ba3Y2（BO3）n：Eu^3＋ phosphor was measured. The results showed that the emission intensity increased with increasing Eu^3＋ concentration, and then decreased. The CIE color coordinates of Ba3Y2（BO3）4：Eu^3＋ phosphor were x=0.641 and y=0.359 at 15 mol.% Eu^3＋.     

Luminescent properties of Eu3+-doped BaZrO3 phosphor for UV white light emitting diode

A novel orange phosphor Eu³⁺ doped barium zirconate (BaZrO₃) was synthesized by conventional solid state reaction method and its crystal structure and luminescent properties were investigated in this paper. The X-ray diffraction patterns (XRD) showed that simple BaZrO₃ phase was obtained. Monitoring at 596 nm, the excitation spectrum consisted of a broad band and a series of narrow bands and the stronger excitation peaks located at 275 and 393 nm, respectively. The emission spectrum excited by 393 nm UV light was composed of four narrow bands. The strongest emission was located at 596 nm. The appropriate concentration of Eu³⁺ was 0.025 (molar fraction) for the highest emission intensity at 596 nm. The H₃BO₃ and ammonium were added as flux and the results showed that 2 wt.% NH₄F ions was the optimal flux for BaZrO₃:Eu³⁺.     

Photoluminescence Characteristics of Gd2Mo3O9 ： Eu Phosphor Particles by Solid State Reaction Method

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.     

高分辨率单道扫描型电感耦合等离子体原子发射光谱法测定高合金钢中铝

在测定基体复杂的高合金钢中铝含量时,采用Al 308.215 nm或Al 394.401 nm作为分析谱线,无需使用复杂前处理方法及干扰因子校正模式,使用高分辨率单道扫描型电感耦合等离子体原子发射光谱仪(ICP-AES)对铬、镍质量分数小于20%,铜、锰、钨、钴质量分数小于5%,钼质量分数小于4%的高合金钢中微量铝进行测定。并与普通分辨率全谱电感耦合等离子体原子发射光谱仪测定高合金钢中铝的方法在光谱干扰方面的情况进行了比对。结果表明:方法中铝的测定下限为0.002%(质量分数);校准曲线采用基体匹配法消除基体效应的影响,线性相关系数达0.999 9以上。按照实验方法测定高合金钢样品中铝含量,结果的相对标准偏差(RSD,n=9)不大于6.2%;标准样品中铝的测定结果与认定值相符。     

Combustion synthesis and luminescence properties of blue NaBaPO4:Eu2+ phosphor

The blue-emitting phosphor NaBaPO4:Eu2+ was prepared by the combustion method. The phase structure and microstructure of the as-prepared samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Under the excita-tion wavelength of 360 nm, the emission spectrum exhibited only one blue band centering at 435 nm, which was ascribed to the 4f65d1→4f7 transition on Eu2+ ions. Compared with the phosphor obtained by solid-state reaction method, the relative emission intensity of sample ob-tained by combustion method increased slightly. The decay times and the temperature dependence luminescence intensities (25-300 oC) were discussed in order to further investigate the potential applications. Furthermore, Eu2+-doped NaBaPO4 phosphor showed higher thermally sta-ble luminescence comparable to commercially available Y3Al5O12:Ce3+ (YAG:Ce3+) phosphor. All the investigated suggestions that Na-BaPO4:Eu2+ is a good phosphor candidate applied in white light emitting diode.