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1.
Sm3+掺杂CaO-SiO2-B2O3发光玻璃的制备、表征及性质   总被引:1,自引:0,他引:1       下载免费PDF全文
用高温固相法合制备了以CaO-SiO2-B2O3为基质,Sm3+为激活离子的发光玻璃。对Sm3+的淬灭浓度、基质中的硼硅比例、其他稀土离子的敏化作用以及基质组成等因素对玻璃发光特性的影响进行了探讨,并用红外和X-衍射分析对样品的结构进行了表征。结果表明:当Sm3+掺杂的物质的量分数为1.2%,激发波长λ = 404 nm时,玻璃体60CaO-20SiO2-20B2O3∶1.2Sm3+的发光强度为4 838 A.U.( λ = 606 nm );这种发光玻璃具有将紫外及近紫外光转换为橙红色光的特点。少量的Eu3+的掺入,对玻璃体的发光起敏化作用;玻璃体中的组分CaO可被ZnO替代。  相似文献   

2.
An modified laminar crystal sodium silicate(Al-SKS-6)was synthesized by spray drying and high temperature crystallization using sodium silicate as silicon source,Al atom as inorganic source and hexadecyltrimethy ammomum bromide(CTMAB)as the structure template.The hydrothermal stability of product was at least 1 h.The synthesized material was characterized by XRD and SEM.The results indicated that shape and intensity of XRD diffraction peak at 20 took changes.but raw material δ phase crystal form kept unchanged.and assured high Ca2+ and Mg2+ binding capacity of the products.The Ca2+ and Mg2+ binding capacity of product is up to 380 mg Ca/g and 410mg Mg/g respectively.It was found that the hole of product became smaller and appeared rod structure based on SEM. The hydrothermal stability was increased due to the pillaring of A1 atom.  相似文献   

3.
用十六烷基三甲基溴化铵(CTAB)/正丁醇/正辛烷/钐盐水溶液(氨水)所形成的反相微乳液体系, 控制合成Sm2O3球形纳米粒子. 绘制出25 ℃下CTAB/正丁醇/正辛烷/钐盐水溶液(氨水)体系的拟三元相图, 得到了反相微乳液区.在此反相微乳区内合成了Sm2O3的前驱体, 对前驱体进行热分析(TG-DSC), 确定了得到纳米Sm2O3产物的适宜焙烧温度为900 ℃, 并考察了微乳液中反应物浓度、反应时间等因素对合成产物的影响. 采用X射线衍射(XRD)、透射电镜(TEM)、激光粒度仪(NSA)、荧光光谱(FS)仪等分析方法对Sm2O3产物的形貌、晶形、粒径及荧光性质进行了表征. 结果表明, 25 益下利用反相微乳液法, 成功地制备了粒径分布较窄、分散性良好的球形纳米Sm2O3粒子, 粒径约20 nm左右, 且表现出较强的荧光性质.  相似文献   

4.
用水热法合成了1个新的锌配合物[Zn(bibm)(glu)]n(bibm=4,4′-二(苯并咪唑-1-甲基)联苯;glu=戊二酸),对它进行了红外光谱、元素分析、XRD、热重和荧光等表征,并用X-射线单晶衍射法测定了配合物的单晶结构。该配合物属单斜晶系,P21/n空间群,为二维层状结构。实验结果表明该配合物具有较好的荧光性质,是潜在的荧光光学材料。  相似文献   

5.
导电含硫材料/聚苯胺复合物作为镁二次电池的正极材料   总被引:6,自引:0,他引:6  
使用通过简单加热聚丙烯腈(PAN)和硫单质而得到的导电含硫材料(conductive sulfur-containing material, CSM)及其与聚苯胺(PAn)的复合物作为镁二次电池的正极材料. X射线衍射(XRD)和傅立叶红外光谱(FT-IR)测试表明, 导电含硫材料的结构由类似石墨的微晶相及无定形相所组成, 材料骨架为含有S—S键的脱水嘧啶型基质. 该导电含硫材料与聚苯胺复合并掺杂Cu(II)后, 其放电比容量和电化学可逆性大大提高, 放电比容量可达117.3 mAh·g-1, 22次循环后容量保持大约78%(相对于第二次放电容量). 聚苯胺不仅起到电化学催化剂的作用, 同时也是电极活性物质, 并且在分子水平上改善了活性材料的导电性能. 该复合物研究结果为镁二次电池正极材料结构设计的开发提供了新的思路.  相似文献   

6.
采用甘氨酸-硝酸盐法(GNP)合成了La0.5RE0.3Sr0.2FeO3-δ(RE=Nd、Ce、Sm)系列复合氧化物粉体. 用X射线衍射(XRD)和TG-DSC分析了样品钙钛矿物相的形成过程, 用Archimedes排水法测量体积密度并计算烧结样品的相对密度, 用四端子技术测量电导率. 结果显示, 掺Nd的样品1200 ℃烧结2 h成为单一立方钙钛矿结构, 掺Ce样品有明显的CeO2立方相析出, 掺Sm样品主相为钙钛矿结构伴有微弱的杂峰. 1250 ℃烧结2 h的La0.5Nd0.3Sr0.2FeO3-δ在600 ℃时电导率高达100 S•cm-1以上, 明显高于La0.5Ce0.3Sr0.2FeO3-δ及La0.5Sm0.3Sr0.2FeO3-δ样品的电导率, 预示着La0.5Nd0.3Sr0.2FeO3-δ可能是一种良好的中温固体氧化物燃料电池(SOFC)阴极材料.  相似文献   

7.
以天然物质石斛为原料,一步水热法合成高荧光量子产率的氮掺杂碳点(NCDs),通过透射电子显微镜(TEM)、X射线光电子能谱(XPS)、傅里叶变换红外光谱(FT-IR)、紫外-可见光吸收图谱(UV-Vis)及荧光光谱(PL)对合成的NCDs进行表征。 实验结果显示合成的NCDs发强烈的蓝色荧光,呈现为球形或准球形,均匀分散,尺寸范围在1~5 nm;其表面含有丰富的COOH、OH和NH2等水溶性基团,最佳激发和发射波长分别为350和435 nm,且具有良好的发光稳定性。 通过测定,合成的NCDs的荧光量子产率高达29.19%。在pH=7.4的缓冲溶液中测定不同物质对NCDs的荧光影响,相同条件下发现只有阿莫西林能够对NCDs荧光进行明显猝灭,表明合成的NCDs可选择性的识别阿莫西林,通过NCDs的荧光强度变化构建一种可灵敏检测阿莫西林的传感器,检测线性范围为2.6~30 μmol/L,检出限为0.15 μmol/L。  相似文献   

8.
Biocompatible chitosan‐based polyelectrolyte complexes (PECs) doped with xanthene dyes (fluorescein, eosin Y, erythrosin B, rhodamine 6G) were synthesized and characterized by scanning electron microscopy, dynamic light scattering, zeta potential measurements, and absorption and luminescence (including polarized, time‐resolved, and phosphorescence) spectroscopy. The results are discussed in terms of the mechanism and rigidity of dye–PEC binding, the heavy‐atom effect in dyes and PEC stability. Eosin Y is found to be the optimal dopant, providing both a high dye content in PECs and a high quantum yield of fluorescence.  相似文献   

9.
《Solid State Sciences》2012,14(4):488-494
Un-doped and doped ZnO nanoparticles (Zn0.97X0.03O-NPs, X = Mn, Co, and Ni) were synthesized from a metal acetate precursor and acetic acid by a modified sol–gel combustion method. The compounds were synthesized at calcination temperatures of 650 °C for 1 h. The synthesized un-doped/doped ZnO-NPs were characterized by X-ray diffraction analysis (XRD) and high-magnification transmission electron microscopy (TEM). The XRD results revealed that the sample product was crystalline with a hexagonal wurtzite phase. The TEM showed ZnO-NPs nearly spherical shapes and a non-uniform shape for doped ZnO-NPs. The crystalline development in the ZnO-NPs was investigated by X-ray peak broadening. The size–strain plot (SSP) method was used to study the individual contributions of crystallite sizes and lattice strain on the peak broadening of the un-doped and doped ZnO-NPs. Physical parameters such as strain, stress and energy density values were calculated more precisely for all reflection peaks of XRD corresponding to the wurtzite hexagonal phase of ZnO lying in the range of 20–80° from the SSP results. The vibrating sample magnetometer (VSM) was also used to study the magnetic behavior of the samples in the ceramic form. The obtained results showed that strain play an important role in peak broadening; moreover, the mean crystalline size of the un-doped and doped ZnO-NPs estimated from the TEM and the SSP method were highly inter-correlated.  相似文献   

10.
通过在水平管式炉中用石墨还原锑掺杂二氧化锡(ATO)纳米颗粒的方法制备了ATO的实心球和空心球, 并用EDX和XRD等技术分析了产物的物相和元素组成; 用FE-SEM和TEM观察了其形貌; 用HRTEM分析了其晶格结构. 结果表明, 产物为直径0.2~5 μm的ATO实心球和直径为2~20 μm的ATO空心球. 通过控制Ar流速和沉积位置控制了ATO实心球的尺寸和产量, 用Ostwald Ripening分析了ATO实心球的生长过程. ATO空心球的制备在具有较高氧浓度、长度稍长于刚玉管的陶瓷管中进行, 对其生长机理进行了讨论, 分析了相同条件下使用不同材质的管子生成不同形貌产物的原因.  相似文献   

11.
用L-半胱氨酸(L-cysteine)作为稳定剂,以制备的CdTe量子点为核模板,水相合成了具有近红外发光的Ⅱ型核壳CdTe/CdSe半导体量子点。实验考察了合成温度,核模板的尺寸和组分比等因素对合成高质量的CdTe/CdSe量子点的影响。用紫外-可见吸收和荧光光谱研究了合成的量子点的光学性质。在优化的合成条件下,荧光发射光谱在586~753nm范围连续可调,荧光量子产率高达68%;通过X-射线衍射(XRD),X射线光电子能谱(XPS)和透射电镜(TEM)对合成的Ⅱ型核壳CdTe/CdSe量子点进行了结构和形貌表征。  相似文献   

12.
以磷酸三丁酯作为配体,使用高温溶液法合成了掺铒磷酸镧纳米晶体,高分辨电镜和XRD结果表明产物尺寸均一,直径4nm左右,具有高度的结晶性,在甲苯等有机溶剂中分散性良好.近红外发光光谱表明,产物在1535 nm处有发光峰,半高全宽为50 nm,高于目前掺铒光纤放大器(EDFA)的增益带宽.通过IR、元素分析研究发现,使用真空干燥等方法不能有效去除纳晶表面的羟基.为了进一步消除表面缺陷和猝灭基团对纳晶发光性质的影响,我们尝试在其外围生长一层LaPO4壳做成核壳粒子以消除表面缺陷和隔离猝灭基团,结果表明,新的纳晶的发光强度得到了显著提高.  相似文献   

13.
纳米荧光粒子YVO_4∶Eu的合成及其在指纹显现中的应用   总被引:1,自引:0,他引:1  
以柠檬酸为络合剂,在水相中合成了悬浮稳定性较好的稀土YVO4∶Eu溶胶,采用XRD、TEM、荧光光谱等技术,研究了稀土荧光粒子的尺寸、形貌、晶胞参数及发光性能.结果表明合成的YVO4∶Eu荧光粒子为四方晶系,粒径约为10nm,分散性较好;在pH=9.0时合成的Y0.7VO4∶Eu0.3溶胶具有最大的荧光强度,其最大发射峰在619nm;经乙二胺四乙酸二钠表面修饰后的Y0.7VO4∶Eu0.3纳米荧光粒子能够清晰地显现出光滑客体上的指纹,颜色为红色.  相似文献   

14.
Nanosized crystallites of rare earth doped ceria Ce0.9Ln0.1O1.95 (Ln = Nd, Sm, Gd) a promising electrolyte material for Intermediate Temperature – Solid Oxide Fuel Cells/electrolysis cells have been synthesized by standard ceramic route. Detection of impurities in the samples was done by FTIR spectroscopy. X-ray diffraction studies were used for the determination of phase purity, crystal structure and average crystallite size of the samples. Kinetics involved in phase formation has been discussed. Raman study showed a major band around 465 cm−1 in all the samples, which is attributed to the cubic fluorite structure of ceria. It was also found that for samples Ce0.9Ln0.1O1.95 (Ln = Nd, Sm, Gd) the frequency of F2g shifts to lower value. Electrochemical impedance spectroscopy has been used to measure the ionic conductivity of the samples at elevated temperatures. The Gd doped sample showed the highest grain boundary and total conductivity in comparison to Sm and Nd doped sample. Bulk thermal expansion behavior, sintered densities and micro structural features of the samples have also been studied.  相似文献   

15.
报道了应用于溶液法制备器件的小分子蓝光主体材料2-叔丁基-9,10-二(9,9-二正丙基芴基)蒽(TBPFA), 合成路线如Scheme 1所示, 该化合物具有较高的荧光量子效率,以它作为主体材料, 采用旋涂法制备了掺杂与非掺杂型单层器件, 并对器件性能进行了初步研究.  相似文献   

16.
合成了一类组成为[(n-C4H9)4N][EuxM1-x(TTA)4](M=La、Sm、Gd、Tb)的固体配合物,通过测定其红外光谱,X射线粉末衍射谱和荧光光谱,研究了配合物结构和发光性质随Eu^3 浓度变化的规律。红外光谱和XRD谱的分析结果表明,在体系中没有新化合物生成,而荧光光谱分析结果表明发光强度与Eu^3 浓度不成线性关系,不发光的基质配合物组分对发光有不同大小和不同类型的影响,提出一种可能的发光机制解释这一共发光现象。  相似文献   

17.
Three new quinoline and di-tert-butyl phenothiazine isomeric derivatives were synthesized and characterized towards applications for oxygen sensing and optical information multicoding. The compounds with phenylene linker showed outstanding phase-dependent reversibility between ON/OFF states (low and high emission intensity, drastic shifting of emission colors, short- and long-lived fluorescence) in systematic grinding/fuming cycles, as required for multichannel memory devices based on optical information multicoding. The conformational diversity of the phenothiazine unit resulted in dual emission of the doped films implemented by the different luminescence mechanisms with peaks located at 414/530, 416/540, and 440/582 nm. The presence of a phenylene linker and thus two rotational degrees of freedom resulted in quenching of the delayed fluorescence of quasi-equatorial conformers in the solid state. The compound containing no phenylene bridge was characterized by two different driving photoluminescence mechanisms of the doped films: short fluorescence of the quasi-axial conformer and thermally activated delayed fluorescence of the quasi-equatorial form. This compound showed oxygen sensitivity with a Stern–Volmer constant of 7.5×10−4 ppm−1.  相似文献   

18.
Frank and Bard firstly reported that suspending TiO2 powder could photo-catalyze the solution con-taining CN?. Research on photo-degradation of delete-rious pollutants with nano-semiconductor material has become one of the most popular topics. Owing to it…  相似文献   

19.
通过红外光谱、紫外可见光谱、荧光光谱和X射线粉末衍射等测试手段,对溶液中合成的喹哪啶酸合铕(Eu-qina)配合物进行了表征,且将溶胶-凝胶法合成出的Eu-qina/SiO2杂化发光材料,与溶液中合成的配合物Eu-qina进行对比.结果表明,配合物Eu-qina中由于喹哪啶酸能有效地将能量传递给Eu3+离子,使Eu3+发出较强的红色特征荧光,而杂化材料Eu-qina/SiO2因SiO2的加入使荧光强度增大.当Eu-qina配合物的掺杂量达到一定值时,Eu-qina/SiO2发较强的红光,并由晶态的Eu-qina转化为非晶态的Eu-qina/SiO2.  相似文献   

20.
《印度化学会志》2022,99(12):100756
In this paper, we report the successful fabrication of a novel dye-sensitized solar cell (DSSCs) using Mg doped ZnO as photoanode and natural dye Terminalia catappa as sensitizer. We synthesized Mg doped ZnO nanoparticles at different Mg concentrations (2%, 4%, 6%, and 8%) by employing a simple solvothermal route. The structural, morphology, composition and optical investigations of synthesized Mg doped ZnO nanoparticles are carried out using XRD, FE-SEM, EDAX, TEM, SAED, FTIR and UV–visible measurements. The XRD results confirmed the formation of hexagonal-wurtzite structure for the Mg doped ZnO nanoparticles and increase of crystalline size with increasing dopant concentration up to 6% is observed. FESEM analysis indicated a gradual change in the surface morphology with increasing Mg concentration and the size of the nanoparticles are slightly reduced at higher Mg concentration. The HRTEM images and SAED pattern also confirmed the formation of wurtzite hexagonal phase of ZnO. The band gap energies calculated from the UV–visible spectra using Tauc's plots indicated decrease of band gap energy with dopant concentration. The DSSCs fabricated using Mg doped ZnO photo-anodes and Terminalia catappa sensitizer showed higher efficiency at higher Mg concentration and observed increase in efficiency is discussed based on slower charge carrier recombination and higher carrier life time as evidenced from the electrochemical impedance analysis.  相似文献   

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