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1.
曹玮  曲波  钟惠民  袁瑾 《光谱实验室》2003,20(2):247-249
本文研究了金属铋离子与胱氨酸配合物的合成方法,采用X射线粉末衍射光谱对配合物进行了分析鉴定,结果表明,Bi^3 能与Cys形成配合物。  相似文献   

2.
稀土三元配合物粉末和凝胶共发光效应的光声光谱研究   总被引:2,自引:1,他引:1  
合成了Eu(TTA)3·Phen和Eu0.8Y0.2(TTA)3·Phen固体配合物微晶粉末及其掺杂的SiO2凝胶样品。在300-800nm测定并解释了其光声光谱。在配体吸收处,Eu0.8Y0.2(TTA)3·Phen的光声强度低于Eu(TTA)3·Phen的光声强度;而对于配合物掺杂的凝胶样品,则情况相反。Y^3+的引入改变了配合物的弛豫过程,且配合物在粉末和凝胶状态下,弛豫历程不尽相同。结合荧光光谱研究了标题化合物的发光特性,并建立了能量传递模型。  相似文献   

3.
钐的聚酰亚胺配合物的微波辐射固相配位合成和表征   总被引:2,自引:1,他引:1  
钐离子(Ⅲ)与苯代三聚氰胺和2,4-甲苯基二异氰酸酯(TDI)生成的聚脲再与均苯四酸二酐生成的聚酰亚胺的固相配位反应。考察了微波辐射时间(功率)、稀土离子和聚合物的配比以及温度等因素对配合物产率及配合物中钐离子含量的影响,测量了配合物的红外光谱、拉曼光谱、扫描电镜、^13C固体核磁共振及X-射线粉末衍射等,并推测了配合物可能的结构。测定了配合物中钐离子的含量,通过荧光发射光谱测量了配合物的荧光发射强度,并与相应的常规加热配位进行比较。通过磁化曲线测量了配体和配合物的磁性能。实验结果表明:此类配合物不具有钐离子的特征荧光峰,钐离子的第一激发态能级和配体的三重态能级之间不能匹配。另外配合物显示出稀土离子的优良的磁性能。  相似文献   

4.
烟酸锌配合物的合成及其表征   总被引:1,自引:0,他引:1  
以烟酸与七水硫酸锌为原料合成了烟酸锌配合物,并用摩尔电导、元素分析、红外光谱、电子吸收光谱、以及X射线粉末衍射光谱对所合成的配合物进行了表征,据表征结果提出了烟酸锌配合物的可能结构。  相似文献   

5.
钆(Ⅲ)天冬酰胺席夫碱配合物的EPR波谱   总被引:3,自引:0,他引:3  
考察了两类新的Gd^3+氨基酸席夫碱配合物在不同温度下的多晶粉末和有机溶剂中的EPR波谱,首次测定了水扬醛缩天冬酰席夫碱钆配合物在DMSO中变温EPR特性,发现随温度降低线宽单调减小,纵向弛豫时间下T1依次增大,用自旋晶格相互和机理作了解释。  相似文献   

6.
首次用碳酸铷与NTO在水溶液中直接合成了Rb+ 与NTO- 的配合物。采用元素分析和化学分析确定配合物的组成为Rb(NTO)·(H2 O)。用X 射线粉末衍射谱的测试与分析对该配合物进行了结构和性质的表征。给出了FTIR和Raman光谱 ,分析了各种谱线的归属。从结构角度讨论了配合物中不同键的形成。  相似文献   

7.
本文报道了Eu(Ⅲ)与烟酸及邻菲咯啉形成的三元固态配合物。通过元素分析,热谱分析和摩尔电导确定其化学组成为RE(Phen)L3,并利用红外,紫外光谱、核磁共振谱和X-射线粉末衍射对配合物进行了表征。研究了配合物的荧光性质。  相似文献   

8.
本文报道了Eu(Ⅲ)与烟酸(HL)及邻菲咯啉(Phen)形成的三元固态配合物。通过元素分析、热谱分析和摩尔电导确定其化学组成为RE(Phen)L3,并利用红外、紫外光谱、核磁共振谱和X-射线粉末衍射对配合物进行了表征。研究了配合物的荧光性质。  相似文献   

9.
铕-苯甲酸-邻菲咯啉掺杂配合物体系的合成与荧光性能研究   总被引:21,自引:4,他引:17  
合成了Eu1-xLnx(BA)3 Phen(Ln: Gd,La,Y;BA: 苯甲酸;Phen: 1,10-邻菲咯啉)系列固体粉末配合物。红外光谱的研究表明该系列配合物具有相似的结构;荧光光谱表明该类配合物均能发出强的铕离子的特征荧光,并且掺杂元素能增强配合物的发光性能,起到共发荧光作用。  相似文献   

10.
合成了Eu(TTA) 3 ·Phen和Eu0 .8Y0 .2 (TTA) 3 ·Phen固体配合物微晶粉末及其掺杂的SiO2 凝胶样品 .在30 0~ 80 0nm测定并解释了其光声光谱 .在配体吸收处 ,Eu0 .8Y0 .2 (TTA) 3 ·Phen的光声强度低于Eu(TTA) 3 ·Phen的光声强度 ;而对于配合物掺杂的凝胶样品 ,则情况相反 .Y3 + 的引入改变了配合物的弛豫过程 ,且配合物在粉末和凝胶状态下 ,弛豫历程不尽相同 .结合荧光光谱研究了标题化合物的发光特性 ,并建立了能量传递模型 .  相似文献   

11.
ZnO thin films containing nano-sized pores were synthesized on solid substrates through a sol–gel process by accommodating cetyl-trimethyl-ammonium bromide (CTAB) as an organic template in the precursor solution. By X-ray diffraction the resultant ZnO films were found to possess ordered pore arrays forming lamellar structure with the spacing between two adjacent pores being ∼3.0 nm. Photoluminescence measurements indicated that the surfactants effectively passivated the surface defects of the ZnO films responsible for the green emission. Al doping was found to improve not only the lamellar structure of the pore arrays but also the near-band-gap emission intensity while the suppression effect of CTAB on the green emission remained undisturbed. With a proper control of doping level, the optical property as well as the structural integrity can be tailored to augment the potential of ZnO films for the optoelectronics and sensor applications.  相似文献   

12.
测量了不同组份比例x的CdS_xSe_(1-x)/ZnS(核/壳)量子点的吸收谱和发射谱,确定了量子点的吸收系数、吸收截面和发射截面.量子点吸收截面随粒径的增大而增大、随x的增大而减小.采用紫外固化胶,制备了掺杂浓度为0.1~5mg/mL的CdS_(0.4)Se_(0.6)/ZnS量子点光纤,测量了不同掺杂浓度量子点光纤中473nm泵浦功率的吸收衰减速率.吸收衰减速率和吸收截面弱关联于掺杂浓度.测量了光致荧光光谱强度随光纤长度和量子点浓度的变化.量子点光纤的光致荧光峰值强度随掺杂浓度和光纤长度变化而变化,且存在一个与最大峰值强度对应的饱和掺杂浓度和光纤长度.本文的实验结果有助于进一步构建新型的CdS_xSe_(1-x)/ZnS量子点增益型光电子器件.  相似文献   

13.
We report systematic study of structural, phonon and optical properties of Cr-doped ZnO nanoparticles. These particles are synthesized through simple sol–gel technique. Structural studies carried out by X-ray diffraction method, confirm that the prepared particles are in hexagonal wurtzite structure and lattice parameters change considerably while increasing the doping. Raman and Fourier transform infrared spectral studies show that the intensity of the phonon modes decreased and also blue shift due to ion doping, respectively. Apart from this, transmission electron microscopic studies show reduction in particle size where the particle diameters reduced from 36 to 11 nm. Optical absorption spectral measurements show a blue shift in the band-gap and increment in excitonic oscillator strength. Photoluminescence studies show doping altered the near-band edge emission but there is no change in the other emission bands which is due to oxygen vacancy, surface defects and surface dangling bonds.  相似文献   

14.
Enhancement of the UV photoluminescence emission of sol–gel synthesized tin oxide nanoparticles is achieved by a combination of thermal annealing and Co doping. The UV as well as the defect-related visible photoluminescence are correlated to the structural characteristics and surface Sn(OH)2 content. The nanoparticle structure, size, crystallinity, and Sn(OH)2 content are monitored by a combination of X-ray diffraction, transmission electron microscopy, and Raman spectroscopy. In the undoped powders, a suitable annealing leads to a significant UV luminescence at around 365 nm. After doping with Co and annealing, the UV emission is further enhanced. The improvement in the UV emission intensity following annealing and Co doping of SnO2 is demonstrated to be due to a reduction in the hydroxyl content. The defect-related broad visible photoluminescence (~400–650 nm) can be deconvoluted into three bands at around 440 nm (blue), 510 nm (green), and 600 nm (orange). The green emission is related to Sn(OH)2 determined by Raman spectroscopy. The blue and orange emissions are attributed to oxygen vacancies.  相似文献   

15.
Al doped ZrO2 thin films were deposited on quartz substrates by sol–gel dip coating technique. X-ray diffraction pattern showed the deterioration of the crystallinity of the films with increase in Al doping concentration due to the formation of stress in the film. Scanning electron microscope images showed crack free surface. An average transmittance of >80% (in UV–vis region) was observed for all samples. Optical band gap was found to vary as a function of doping concentration. Photoluminescence spectra of the films exhibited an increase in the emission intensity with increase in Al doping concentration which is due to the increase in oxygen vacancies in the Al doped films. The “Blueshift” and “Redshift” of the PL spectra with increase in Al concentration originates from the change of stress in the films. The enhancement of PL intensity in the Al doped ZrO2 thin films make it suitable for generation of solid state lighting in light emitting diode.  相似文献   

16.
以乙腈为溶剂、γ-CuⅠ粉末为原料,采用溶剂蒸发法,通过工艺优化,生长出了尺寸约为9 mm×9 mm×1 mm的透明γ-CuⅠ闪烁晶体。卢瑟福背散射谱(RBS)实验结果表明,所生长的γ-CuⅠ晶体中铜和碘元素的比例分别为53.1和46.9 mol%。在生长溶剂中掺入适量碘可提高γ-CuⅠ晶体中碘的比重,所获得晶体中铜和碘元素的比例被调整为50.4和49.6 mol%。光致发光谱(PL)的结果表明,所生长的γ-CuⅠ晶体存在有410 nm发射峰和720 nm附近的宽发射带,掺碘后720 nm的宽发射带得到了较大幅度的抑制,但同时也会在424和474 nm处出现两个相对较弱的发射峰;X射线激发发射谱(XEL)显示,所生长的CuⅠ晶体存在有435 nm发射峰和720 nm附近的宽发射带,掺碘后720 nm的宽发射带得到了较大抑制。综合掺碘前后γ-CuⅠ晶体的发射光谱可以发现:碘元素有助于抑制γ-CuⅠ晶体的红光发射,其原因来自于碘元素的体掺杂造成晶体中碘空位的减少,而非由晶体表面的吸附碘。  相似文献   

17.
Yb3+ and Er3+ co-doped GdAlO3 phosphors are prepared by the sol–gel method. The effect of doping concentration on the structure and fluorescence properties is investigated by X-ray diffraction (XRD) and photoluminescence, respectively. XRD pattern indicates that the sample structure belongs to orthorhombic. The photoluminescence results show that both green and red fluorescence emission and upconversion emission intensities decrease with an increase in Yb3+ concentration due to the cross-relaxation process between Yb3+ and Er3+ ions. Based on the emission spectra, the mechanism of the upconversion emission is discussed, and we concluded that the upconversion emission is a two-photon process.  相似文献   

18.
Ga doped ZnO nanorod arrays were prepared on silicon substrates in a mixture solution of zinc nitrate hexahydrate, methenamine, and gallium nitrate hydrate. Effect of synthesis conditions on crystal structures, morphologies, surface compositions, and optical properties was analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and photoluminescence techniques (PL). Experimental results reveal that Ga doping amount can reach 1.67 at% with the increase of gallium nitrate concentration. Ga doping greatly affects the morphologies of ZnO nanorod arrays. The photoluminescence spectra show a sharp UV emission and a broad visible emission. With Ga doping, UV emission has an apparent broadening effect and its peak shifts from 3.27 eV to 3.31 eV. The intensity ratio of UV emission to visible emission demonstrates that appropriate Ga doping amount is beneficial for the improvement of ZnO crystalline quality.  相似文献   

19.
The Zn1−xYxO nanoparticles with good optical properties have been prepared by sol–gel method. The yttrium doping effect on the structures and optical properties were investigated by XRD, SEM, XPS and low temperature photoluminescence. The UV emission intensity of yttrium doped ZnO was over 300 times stronger than that of pure ZnO, which was an exciting result in enhancing the ultraviolet near band edge emission in photoluminescence from ZnO nanoparticles. The UV emission band of doped ZnO nanoparticles exhibits a red shift from 388 to 398 nm, indicating a shallow energy level near valence band has been formed due to the yttrium doping into ZnO lattices. The defect-related band is suppressed (ID/IUV = 1–0.83) considerably in Zn1−xYxO nanoparticles, revealing the quenching of the broad yellow-orange emission. The doping effect on the optical properties is investigated by temperature dependent photoluminescence. The experimental results indicated that the donor level of yttrium is deeper than that of undoped ZnO.  相似文献   

20.
以亚甲基双丙烯酰胺为网络剂,采用高分子网络凝胶法合成了Sr2CeO4∶Dy3+荧光粉,并表征其结构、颗粒形貌及发光性能。研究结果表明:Sr2CeO4∶Dy3+无其他杂相存在且粉末颗粒大小均匀。其紫外-可见吸收带集中在480 nm附近;在370 nm紫外光激发下,其发射图谱为一多峰发射;监测470 nm的发射峰,所得样品的激发谱为一双峰宽谱,峰位为292和338 nm。同时研究了Dy3+掺杂浓度对样品发射光谱的影响,结果显示,随着Dy3+浓度的增大,其黄、蓝发射峰强度比值逐渐增大,但发光强度呈现先增大后减小的趋势,在Dy3+掺杂浓度为0.4 mol%时达到最大值。  相似文献   

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