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微纳Fe3O4磁粉的制备及其荧光复合改性 预览
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作者 陈金鹏 舒霞 +4 位作者 洪勇 蒋富强 巩文智 张勇 吴玉程 《中国粉体技术》 CAS CSCD 2020年第1期61-67,共7页
采用化学共沉淀法制备磁粉,以稀土钠离子掺杂的铝酸疑为发光材料,采用微胶囊法对磁粉进行荧光复合改性,探索其在无损检测领域的应用灵敏度;运用SEM、TEM、XRD、VSM和PL谱等手段对磁粉进行表征和性能检测。结果表明:化学共沉淀法制备的... 采用化学共沉淀法制备磁粉,以稀土钠离子掺杂的铝酸疑为发光材料,采用微胶囊法对磁粉进行荧光复合改性,探索其在无损检测领域的应用灵敏度;运用SEM、TEM、XRD、VSM和PL谱等手段对磁粉进行表征和性能检测。结果表明:化学共沉淀法制备的磁粉物相为Fe3O4,其单个颗粒尺寸约为10 nm,为纳米级近球形颗粒;其团聚体的尺寸范围为70-600nm,为微米级聚集态;荧光改性后的SrAl2O4(Eu)-Fe3O4磁粉在近可见光激发下发射出明亮的绿色荧光(约为514 mn);荧光磁粉应用于实际微裂纹检测的灵敏度明显优于普通磁粉。 展开更多
关键词 Fe3O4磁粉 荧光磁粉 无损检测 光致发光
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SiC纳米颗粒的制备与发光特性研究 预览
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作者 刘霞 曹连振 +1 位作者 蒋红 宋航 《功能材料》 EI CAS CSCD 北大核心 2019年第9期9093-9096,9101共5页
采用热化学气相沉积的方法首先合成了SiC纳米颗粒。接着,用扫描电子显微镜、透射电子显微镜、拉曼光谱、X射线电子能谱和X射线衍射谱等表征了材料的结构和组成。最后,利用光致发光谱和光致发光谱微区成像系统研究了材料的光学性质。实... 采用热化学气相沉积的方法首先合成了SiC纳米颗粒。接着,用扫描电子显微镜、透射电子显微镜、拉曼光谱、X射线电子能谱和X射线衍射谱等表征了材料的结构和组成。最后,利用光致发光谱和光致发光谱微区成像系统研究了材料的光学性质。实验结果表明,制备的纳米材料的尺寸约为70~90 nm;发光带由中心波长分别为530和542 nm的绿光发光峰组成,分析认为分别来自于SiC材料本身和表面缺陷;在相同的激发光强度下,材料最大发光强度相对于相同条件下合成的体材料提高5倍左右。制备的SiC纳米材料在绿光光电子器件领域有着潜在的应用价值。 展开更多
关键词 零维SiC颗粒 热化学气相沉积 光致发光 发光机制
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Investigation of Nickel Phthalocyanine Thin Films for Solar Cell Applications 预览
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作者 Eman M. Nasir Mohammed T. Hussein Addnan H. Al-Aarajiy 《材料物理与化学进展(英文)》 2019年第8期158-173,共16页
Ni-Phthalocyanine thin films were thermally evaporated with different substrate temperatures (300 - 450) K on (silicon wafer, glass) substrates. The chemical bonds of NiPc powder were investigated by FTIR spectrum, wh... Ni-Phthalocyanine thin films were thermally evaporated with different substrate temperatures (300 - 450) K on (silicon wafer, glass) substrates. The chemical bonds of NiPc powder were investigated by FTIR spectrum, which introduce good information for NiPc bonds and their locations. The optical properties have been studied by UV-Visible, and Photoluminescence (PL) Spectra. The NiPc thin films have direct gap for all samples. The values of energy gap which is calculated by PL spectra are lower than those calculated by Tauc equation. It is found there are three activation energies, the mobility and concentration of carriers have been measured and, the NiPc films are p-type. P-NiPc/n-Si HJ solar cell was fabricated at substrates temperatures (300, 400) K. From I-V and C-V characteristic, abrupt junction has been found, photovoltaic characteristics have been observed with Voc of (0.335 - 0.415) V, and Isc of (2.77 - 4.26) μA, and the efficiency of (3.08 - 5.03)% at room temperature and substrate temperature (300, 400 K) and under illumination of 55 mW/cm2 using Halogen lamp. Ideality factors of the junction increase from (0.61 - 0.73) and barrier height increases from 2.53 eV to 3.69 eV while shunt resistance decreases from 3.76 KΩ to 2.59 KΩ and series resistance decreases slightly from 0.24 KΩ to 0.23 KΩ. The fill factor decreases from 0.46 to 0.4 with the increase of substrate temperature. 展开更多
关键词 Nickel PHTHALOCYANINE Optical PROPERTY Electrical PROPERTY PHOTOLUMINESCENCE SOLAR Cell
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Photoluminescence of Ag-In-S/ZnS quantum dots: Excitation energy dependence and low-energy electronic structure
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作者 Irina V. Martynenko Anvar S. Baimuratov +8 位作者 Florian Weigert Jose X. Soares Lorena Dhamo Philip Nickl Ilona Doerfel Jutta Pauli Ivan D. Rukhlenko Alexander V. Baranov Ute Resch-Genger 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第7期1595-1603,共9页
Cd-free Ⅰ-Ⅲ-Ⅵ group semiconductor quantum dots (QDs) like Ag-ln-S and Cu-ln-S show unstructured absorption spectra with a pronounced Urbach tail,rendering the determination of their band gap energy (Eg) and the ene... Cd-free Ⅰ-Ⅲ-Ⅵ group semiconductor quantum dots (QDs) like Ag-ln-S and Cu-ln-S show unstructured absorption spectra with a pronounced Urbach tail,rendering the determination of their band gap energy (Eg) and the energy structure of the exciton difficult.Additionally,the origin of the broad photoluminescence (PL) band with lifetimes of several hundred nanoseconds is still debated.This encouraged us to study the excitation energy dependence (EED) of the PL maxima,PL spectral band widths,quantum yields (QYs),and decay kinetics of AlS/ZnS QDs of j different size,composition,and surface capping ligands.These results were then correlated with the second derivatives of the corresponding absorption spectra.The excellent match between the onset of changes in PL band position and spectral width with the minima found for the second derivatives of the absorption spectra underlines the potential of the EED approach for deriving Eg values of these ternary QDs from PL data.The PL QY is,however,independent of excitation energy in the energy range studied.From the EED of the PL features of the AlS/ZnS QDs we could also derive a mechanism of the formation of the low-energy electronic structure.This was additionally confirmed by a comparison of the EED of PL data of as-synthesized and size-selected QD ensembles and the comparison of these PL data with PL spectra of single QDs.These results indicate a strong contribution of intrinsic inhomogeneous PL broadening to the overall emission features of AlS/ZnS QDs originating from radiative transitions from a set of energy states of defects localized at different positions within the quantum dot volume,in addition to contributions from dimensional and chemical broadening.This mechanism was confirmed by numerically modelling the absorption and PL energies with a simple mass approximation for spherical QDs and a modified donor-acceptor model,thereby utilizing the advantages of previously proposed PL mechanisms of ternary QDs.These findings will pave the road to a deeper understanding o 展开更多
关键词 core/shell QUANTUM DOT silver INDIUM sulfide defect PHOTOLUMINESCENCE PHOTOLUMINESCENCE QUANTUM yield single-dot spectroscopy
Nanocoatings on 2D Macroporous Silicon Structures 预览
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作者 Liudmyla Karachevtseva Mykola Kartel +2 位作者 Bo Wang Oleg Lytvynenko Yurii Sementsov 《材料科学与化学工程(英文)》 2019年第7期12-20,共9页
Macroporous silicon formed by photoanodic etching with high aspect ratio and large effective surface is one of the promising materials for the development of 2D photonic structures. We fabricated nanocoatings of CdTe,... Macroporous silicon formed by photoanodic etching with high aspect ratio and large effective surface is one of the promising materials for the development of 2D photonic structures. We fabricated nanocoatings of CdTe, ZnO, CdS surface nanocrystals and SiO2 layers on macroporous silicon surface. The near-IR optical absorption was investigated and well-separated oscillations with giant amplitude were observed in the spectral ranges of surface level absorption. This process is because of resonance electron scattering on the surface impurity states with the difference between two resonance energies equal to the Wannier-Stark ladder. Macroporous silicon structures with SiO2 nanolayers and CdS nanocrystals are proposed to enhance the photoluminescence of CdS nanoparticles with quantum yield 28%. Addition functionalization of 2D macroporous silicon is a result of the high-pressure oxidation. The structural SiO2 reorganization to orthorhombic phase increases the concentration of paramagnetic Pb centers, EPR signal amplitude and GHz radiation absorption. 展开更多
关键词 MACROPOROUS Silicon Surface NANOCRYSTALS SiO2 LAYERS PHOTOLUMINESCENCE High-Pressure OXIDATION
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氮化法合成掺钇氮化铝纳米线 预览
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作者 王秋实 吴宛泽 +1 位作者 谢永辉 王维龙 《电子元件与材料》 CAS CSCD 北大核心 2019年第2期45-48,共4页
采用直流电弧等离子体辅助法,使钇铝合金(Al:Y)和氮气直接反应,成功合成了掺钇氮化铝(AlN:Y)纳米线。用XRD、SEM和拉曼光谱对所制样品的结构和形貌进行了表征,利用PL光谱和磁滞回线研究了AlN:Y纳米线的光学性质和磁性。AlN:Y纳米线长度... 采用直流电弧等离子体辅助法,使钇铝合金(Al:Y)和氮气直接反应,成功合成了掺钇氮化铝(AlN:Y)纳米线。用XRD、SEM和拉曼光谱对所制样品的结构和形貌进行了表征,利用PL光谱和磁滞回线研究了AlN:Y纳米线的光学性质和磁性。AlN:Y纳米线长度约为10μm,直径在40~50nm。纳米线的发光中心位于533nm,展现出了良好的室温铁磁性。 展开更多
关键词 AlN:Y 纳米线 稀土掺杂 光致发光 室温铁磁性 氮化法
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硫化物钝化对InAs纳米线光学特性的影响 预览
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作者 李宝宝 李生娟 +2 位作者 陈刚 李世民 王兴军 《红外与毫米波学报》 SCIE EI CAS CSCD 北大核心 2019年第5期591-597,共7页
针对InAs纳米线表面氧化造成的发光效率低的问题,采用十八硫醇和硫化铵钝化了由化学气相沉积设备生长的闪锌矿结构的InAs纳米线。对硫化物钝化前后的InAs纳米线进行温度依赖的光致发光光谱测试。实验结果表明,十八硫醇和硫化铵钝化的InA... 针对InAs纳米线表面氧化造成的发光效率低的问题,采用十八硫醇和硫化铵钝化了由化学气相沉积设备生长的闪锌矿结构的InAs纳米线。对硫化物钝化前后的InAs纳米线进行温度依赖的光致发光光谱测试。实验结果表明,十八硫醇和硫化铵钝化的InAs纳米线在25 K温度下的发光效率与未钝化的InAs纳米线相比分别提高了~ 6倍和~7倍,此外,可以在室温下探测到硫化铵钝化的InAs纳米线的光致发光,这为未来基于InAs纳米线的中红外纳米光子器件提供了可能性。 展开更多
关键词 砷化铟纳米线 硫化物 表面态 光致发光
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稀土有机配合物的研究进展及应用 预览
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作者 焦晨婕 周彦芳 +1 位作者 章红飞 钟荣 《江西化工》 2019年第2期61-65,共5页
概述了稀土有机配合物的光致发光机理,综述了β-二酮类、有机羧酸类、超分子大环类、高分子等稀土配合物种类,简单介绍了稀土有机配合物在荧光材料、发光材料、磁性材料、防伪油墨等领域的应用,并对稀土有机配合物的研究趋势及应用前景... 概述了稀土有机配合物的光致发光机理,综述了β-二酮类、有机羧酸类、超分子大环类、高分子等稀土配合物种类,简单介绍了稀土有机配合物在荧光材料、发光材料、磁性材料、防伪油墨等领域的应用,并对稀土有机配合物的研究趋势及应用前景进行了展望。 展开更多
关键词 稀土有机配合物 荧光 光致发光 应用
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Photoluminescence properties of blue and green multiple InGaN/GaN quantum wells
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作者 李长富 时凯居 +2 位作者 徐明升 徐现刚 冀子武 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第10期541-545,共5页
The photoluminescence(PL) properties of blue multiple InGaN/GaN quantum well(BMQW) and green multiple InGaN/GaN quantum well(GMQW) formed on a single sapphire substrate are investigated. The results indicate that the ... The photoluminescence(PL) properties of blue multiple InGaN/GaN quantum well(BMQW) and green multiple InGaN/GaN quantum well(GMQW) formed on a single sapphire substrate are investigated. The results indicate that the peak energy of GMQW-related emission(PG) exhibits more significant "S-shaped" dependence on temperature than that of BMQW-related emission(PB), and the excitation power-dependent carrier-scattering effect is observed only in the PG emission;the excitation power-dependent total blue-shift(narrowing) of peak position(line-width) for the PGemission is more significant than that for the PBemission;the GMQW shows a lower internal quantum efficiency than the BMQW. All of these results can be attributed to the fact that the GMQW has higher indium content than the BMQW due to its lower growth temperature and late growth, and the higher indium content in the GMQW induces a more significant compositional fluctuation, a stronger quantum confined Stark effect, and more non-radiative centers. 展开更多
关键词 PHOTOLUMINESCENCE MULTIPLE quantum WELLS localization effect LIGHT-EMITTING diodes
Fluorescence spectra of colloidal self-assembled CdSe nano-wire on substrate of porous Al2O3/Au nanoparticles
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作者 张欣 邵丽萍 +3 位作者 彭嫚 白忠臣 张正平 秦水介 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第6期429-432,共4页
We present a self-assembly method to prepare array nano-wires of colloidal CdSe quantum dots on a substrate of porous Al2 O3 film modified by gold nanoparticles. The photoluminescence(PL) spectra of nanowires are in s... We present a self-assembly method to prepare array nano-wires of colloidal CdSe quantum dots on a substrate of porous Al2 O3 film modified by gold nanoparticles. The photoluminescence(PL) spectra of nanowires are in situ measured by using a scanning near-field optical microscopy(SNOM) probe tip with 100-nm aperture on the scanning near-field optical microscope. The results show that the binding sites from the edge of porous Al2 O3 nanopores are combined with the carboxyl of CdSe quantum dots’ surface to form an array of CdSe nanowires in the process of losing background solvent because of the gold nanoparticles filling the nano-holes of porous Al2 O3 film. Compared with the area of nonself-assembled nano-wire, the fluorescence on the Al2 O3/Au/CdSe interface is significantly enhanced in the self-assembly nano-wire regions due to the electron transfer conductor effect of the gold nanoparticles’ surface. In addition, its full width at half maximum(FWHM) is also obviously widened. The method of enhancing fluorescence and energy transfer can widely be applied to photodetector, photocatalysis, optical display, optical sensing, and biomedical imaging, and so on. 展开更多
关键词 enhanced PHOTOLUMINESCENCE Cd Se NANO-WIRE COLLOIDAL SELF-ASSEMBLED method porous Al2O3 film
Preparation and luminescent properties of CaF2:Ln3+(Ln:Er, Er/Yb)/Nafion composite films
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作者 Limei Song Jianhua Gao +3 位作者 Minmin Liang Xiaojun Li Jiangtao Li Liuchang Wang 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第3期232-236,共5页
In this work, CaF2:Ln3+(Ln:Er,Er/Yb)/Nafion composite films were prepared using Nafion as modifications and matrices by dripping method. The composite films were characterized by Fourier transform infrared spectroscop... In this work, CaF2:Ln3+(Ln:Er,Er/Yb)/Nafion composite films were prepared using Nafion as modifications and matrices by dripping method. The composite films were characterized by Fourier transform infrared spectroscopy(FT-IR), X-ray diffraction(XRD) and scanning electron microscopy(SEM). Composite films are transparent and CaF2:Ln3+(Ln:Er,Er/Yb) nanoparticles are well dispersed in Nafion films.The thicknesses of CaF2:Er3+/Nafion and CaF2:Er3+,Yb3+/Nafion composite film are about 77 and 73 μm,respectively. The nanoparticles in composite film possess cubic phase. CaF2:Er3+,Yb3+/Nafion composite film has stronger characteristic emission of Er3+ around 1530 nm with full width at half-maximum(FWHM) of 73 nm and longer luminescence lifetimes of 22.04 μs(25.03%) and 100.77 μs(74.97%). 展开更多
关键词 CAF2 nanoparticles Photoluminescence ERBIUM NAFION Composite film Rare earths
衬底钝化处理对CsPbBr3量子点薄膜发光稳定性影响 预览
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作者 赵海霞 王新伟 +5 位作者 李如雪 王登魁 方铉 房丹 魏志鹏 王晓华 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第6期1706-1710,共5页
钙钛矿量子点因具有发光谱线窄、发光效率高、发光波长可调谐等优异的光学性能,在照明、显示、激光和太阳能电池等领域得到了广泛研究。然而,钙钛矿材料的稳定性问题,一直制约着其在光电器件中的应用。其中,钙钛矿材料在空气中受潮易分... 钙钛矿量子点因具有发光谱线窄、发光效率高、发光波长可调谐等优异的光学性能,在照明、显示、激光和太阳能电池等领域得到了广泛研究。然而,钙钛矿材料的稳定性问题,一直制约着其在光电器件中的应用。其中,钙钛矿材料在空气中受潮易分解的不稳定性尤为突出,这将严重影响其发光性质。为此,研究人员采用多种手段来改善钙钛矿材料的稳定性。目前,常见的方法是将一些具有疏水性的聚合物材料(例如POSS,PMMA等)引入到钙钛矿纳米晶中,或将钙钛矿纳米晶嵌入到介孔二氧化硅材料中,避免钙钛矿纳米晶暴露于空气中破坏其结构,以此来增强钙钛矿材料的发光稳定性。此外,钝化处理钙钛矿纳米晶表面,也是改善钙钛矿发光稳定性的一种常用方法。这些方法虽然在一定程度上可以改善钙钛矿的发光稳定性,但是在与有机物合成的过程中不免会引入其他有机官能团,介孔二氧化硅的引入,其处理方式相对复杂,而对钙钛矿纳米晶表面的钝化处理会破坏材料的原有结构。以上问题,都会影响钙钛矿的发光性质,不利于其在光电器件中的应用。硅(Si)具有低成本、大尺寸、高质量、导电好等优点,常被选作钙钛矿量子点光电器件的衬底材料。但是,由于Si衬底长时间暴露于空气,其表面易形成一层具有硅烷醇基团(Si—OH)的亲水性薄膜,这将对硅基钙钛矿器件的稳定性产生影响。因此,对Si表面进行钝化处理,破坏其表面Si—OH键,可以降低衬底表面的亲水性,增强疏水性,从而提高钙钛矿材料在器件中的稳定性。本研究使用氢氟酸(HF)对Si衬底表面进行钝化处理,发现钝化处理后的Si衬底表面与水的接触角由50.4°逐渐增大至87.7°,表明Si衬底表面由亲水性逐渐转变为疏水性。利用场致发射扫描电子显微镜(FE-SEM)测试发现,钝化处理后的Si衬底表面变粗糙,并且其表面上的CsPbBr 展开更多
关键词 钝化 衬底 CsPbBr3量子点 稳定性 光致发光
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贵金属纳米颗粒-二维过渡金属硫化物复合纳米结构:制备技术与光电性能综述 预览
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作者 吴治涌 水世显 +2 位作者 张显 杨鹏 万艳芬 《材料导报》 EI CAS CSCD 北大核心 2019年第3期426-432,共7页
过渡金属硫化物是由过渡金属元素和硫族元素构成,结构通式为MX 2,其中M和X分别代表过渡金属和硫族元素。与石墨烯类似,过渡金属硫化物也是二维层状材料,层内由共价键键合形成六角网状结构,层间由范德华力相互作用堆积而成。然而,纯的石... 过渡金属硫化物是由过渡金属元素和硫族元素构成,结构通式为MX 2,其中M和X分别代表过渡金属和硫族元素。与石墨烯类似,过渡金属硫化物也是二维层状材料,层内由共价键键合形成六角网状结构,层间由范德华力相互作用堆积而成。然而,纯的石墨烯的零带隙限制了其在大多数电子和光电子上的应用。相反,已有研究表明,MoS 2由块体材料厚度逐渐减小为单层材料时,其能带结构由间接带隙转变为直接带隙。同样,电子输运测试结果表明,二维过渡金属硫化物具有高的载流子迁移率、大的开关比等。但是二维过渡金属硫化物光吸收及光发射强度低,在很大程度上限制了该材料在光电领域的应用。为了突破二维过渡金属硫化物自身光吸收和光发射强度低的局限性,科研工作者将贵金属纳米颗粒独特的等离激元共振效应作为激发泵浦,增强二维过渡金属硫化物的光致发光效率,使贵金属纳米颗粒-二维过渡金属硫化物复合纳米结构展现出独特的光学性能和电学性能,为其在光学、生物、存储、电学以及催化等领域的应用开辟了新的道路。目前,对贵金属纳米颗粒-二维过渡金属硫化物复合纳米结构的研究,主要集中在利用贵金属纳米球、纳米棒、纳米岛、纳米盘、纳米天线、纳米核壳等结构对光进行汇聚,激发贵金属纳米结构中的表面等离激元,再将能量转移给二维过渡金属硫化物,进而在其中产生高强度的光吸收和光发射,对其光学特性产生明显的调制作用,并研究该复合纳米结构的光致发光和光生电流的增强特性。前期报道中主要采用电子束刻蚀、旋涂、浸润等方法来构筑复合纳米结构,但以上方法构筑的复合纳米结构中贵金属纳米颗粒沉积位置不可控,无序的纳米颗粒易在过渡金属硫化物的边缘和缺陷位置沉积,导致基面位置纳米颗粒厚度不均匀,这就在一定� 展开更多
关键词 贵金属纳米颗粒-二维过渡金属硫化物复合纳米结构 等离激元共振效应 光致发光 光生电流
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多面体共替代对Sr2(Al1–x Mgx)(Al1–x Si1+x)O7:Eu2+晶体结构和发光颜色的影响 预览
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作者 王庆玲 迪拉热·哈力木拉提 +1 位作者 沈玉玲 艾尔肯·斯地克 《物理学报》 SCIE EI CAS CSCD 北大核心 2019年第10期40-46,共7页
采用高温固相法合成Sr1.98(Al1–x Mgx)(Al1–x Si1+x)O7: 2%Eu2+荧光粉完全固溶体,利用X射线衍射、光致发光光谱和光学显微镜进行晶体结构和发光性能的研究. Sr2Al2SiO7和Sr2MgSi2O7同构化合物中包含[MgO4]、[SiO4]和[AlO4]四面体,较... 采用高温固相法合成Sr1.98(Al1–x Mgx)(Al1–x Si1+x)O7: 2%Eu2+荧光粉完全固溶体,利用X射线衍射、光致发光光谱和光学显微镜进行晶体结构和发光性能的研究. Sr2Al2SiO7和Sr2MgSi2O7同构化合物中包含[MgO4]、[SiO4]和[AlO4]四面体,较大体积的[MgO4]和较小体积的[SiO4],共同替代体积相似的[AlO4],导致[(Si/Al)O4]收缩和[(Mg/Al)O4]膨胀,晶胞参数c减少, a和V增大,使Eu2+周围的环境发生改变,晶体场劈裂程度减小,发射峰位从503 nm蓝移至467 nm,实现发光光谱从绿色(0.2384, 0.3919)到蓝色(0.1342,0.1673)的转变.当x为0时,发射峰的半高宽为120 nm, x从0.25增加到1时,半高宽由89 nm逐渐减小至50 nm,多面体的替代会改变荧光粉的发光性能. 展开更多
关键词 Sr2(Al1–x Mgx)(Al1–x Si1+x)O7 光致发光 共替代 配位多面体
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Ce掺杂ZnO的晶体结构、发光和光催化性能的不同机理 预览
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作者 王古平 彭萍萍 +1 位作者 赵森 俞鼎行 《化学工程师》 CAS 2019年第4期13-17,26共6页
采用溶胶凝胶法合成了一系列Ce掺杂ZnO粉晶。采用XRD,UV-VIS,FT-IR,PL技术及以亚甲基蓝溶液脱色反应为模型,研究了Ce掺杂ZnO晶体结构、光学带隙、成键、光致发光及光催化性能产生的不同机理。结果表明:低含量Ce掺杂和高含量Ce掺杂对ZnO... 采用溶胶凝胶法合成了一系列Ce掺杂ZnO粉晶。采用XRD,UV-VIS,FT-IR,PL技术及以亚甲基蓝溶液脱色反应为模型,研究了Ce掺杂ZnO晶体结构、光学带隙、成键、光致发光及光催化性能产生的不同机理。结果表明:低含量Ce掺杂和高含量Ce掺杂对ZnO结构和性能产生的机理存在差异。低含量Ce掺杂时,ZnO晶格参数及Zn-O键长因原子半径大的Ce^3+替代原子半径小的Zn2+而增加,光学带隙因Burstein-Moss效应而宽化,结晶性能因ZnO成核空间增加而提高,青蓝色发光峰因结晶性能提高而减弱。高含量Ce掺杂时,ZnO晶格参数及Zn-O键长因Ce^3+Ce^4+转化而减小,光学带隙因Ce^3+占据Zn^2+格位而减小,结晶性能因氧化铈包覆作用并降低结晶速率而提高,青蓝色发光峰随缺陷增加而增强。Ce掺杂ZnO光催化能力随光学带隙减小而提高。光催化性能最优Ce掺杂量为2%。FT-IR表明系列Ce掺杂ZnO均含有Zn-O和Ce-O-Zn等成键。 展开更多
关键词 铈掺杂 氧化锌 光致发光 光催化
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Stable single photon sources in the near C-band range above 400 K 预览
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作者 Qiang Li Ji-Yang Zhou +3 位作者 Zheng-Hao Liu Jin-Shi Xu Chuan-Feng Li Guang-Can Guo 《半导体学报:英文版》 EI CAS CSCD 2019年第7期80-84,共5页
The intrinsic characteristics of single photons became critical issues since the early development of quantum mechanics. Nowadays, acting as flying qubits, single photons are shown to play important roles in the quant... The intrinsic characteristics of single photons became critical issues since the early development of quantum mechanics. Nowadays, acting as flying qubits, single photons are shown to play important roles in the quantum key distribution and quantum networks. Many different single photon sources (SPSs) have been developed. Point defects in silicon carbide (SiC) have been shown to be promising SPS candidates in the telecom range. In this work, we demonstrate a stable SPS in an epitaxial 3CSiC with the wavelength in the near C-band range, which is very suitable for fiber communications. The observed SPSs show high single photon purity and stable fluorescence at even above 400 K. The lifetimes of the SPSs are found to be almost linearly decreased with the increase of temperature. Since the epitaxial 3C-SiC can be conveniently nanofabricated, these stable near Cband SPSs would find important applications in the integrated photonic devices. 展开更多
关键词 single PHOTON source STABLE PHOTOLUMINESCENCE silicon CARBIDE ELEVATED temperature
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邻苯二酚螯合生长氧化锌棒状结构光致发光增强 预览
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作者 孙杰 房洪杰 +3 位作者 赵俊凤 戴菡 吕正风 汪洪波 《四川大学学报:自然科学版》 CAS CSCD 北大核心 2019年第4期721-726,共6页
通过水热合成方法,研究了邻苯二酚作为螯合剂对氧化锌(ZnO)一维棒状材料结构及其光致发光的作用.实验发现,通过调节邻苯二酚的浓度,可以显著改变ZnO一维棒状材料的形貌特征与长径比.结合XRD测试发现随着邻苯二酚的加入,ZnO一维棒状材料... 通过水热合成方法,研究了邻苯二酚作为螯合剂对氧化锌(ZnO)一维棒状材料结构及其光致发光的作用.实验发现,通过调节邻苯二酚的浓度,可以显著改变ZnO一维棒状材料的形貌特征与长径比.结合XRD测试发现随着邻苯二酚的加入,ZnO一维棒状材料的晶化程度显著提高.随着邻苯二酚加入量增大,ZnO晶体沿(100)面方向呈现择优生长的趋势,当邻苯二酚加入量为1g/L时,ZnO晶体晶化程度最高.另外,光致发光光谱测试发现,ZnO一维棒状材料在紫外以及可见光波段均存在显著的光致发光增强.结合ZnO一维棒状材料的形貌及物相分析,揭示了螯合剂引入后造成的ZnO材料表面缺陷量与晶化程度对光致发光增强的影响.本工作不仅揭示了邻苯二酚在ZnO材料生长中的螯合作用,同时通过邻苯二酚加入量的调控进一步提高了ZnO的光致发光性能. 展开更多
关键词 ZNO纳米晶 光致发光 水热合成 邻苯二酚
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Tetrameric(Bi4I16)4- Iodobismuthate Templated by 1,ω-Bis(isoquinoline)alkane Cation: Structure,Photoluminescence and Enhanced Thermochromism 预览
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作者 汪鹏 陈之荣 李浩宏 《结构化学》 SCIE CAS CSCD 2019年第9期1485-1493,共9页
Using 1,1?-bis(isoquinoline)-1,4-phenyldimethylenyl(BIQPM2+) cation as template, a new tetrameric(Bi4 I16)4-iodobismuthate-containing hybrid with formula of(BIQPM)2(Bi4 I16)·H2 O(1), has been prepared under solvo... Using 1,1?-bis(isoquinoline)-1,4-phenyldimethylenyl(BIQPM2+) cation as template, a new tetrameric(Bi4 I16)4-iodobismuthate-containing hybrid with formula of(BIQPM)2(Bi4 I16)·H2 O(1), has been prepared under solvothermal conditions. The centrosymmetric Bi4-4 I16 tetraanion is constructed from four edge-shared slightly distorted BiI6 octahedrons. Due to the presence of larger conjugated system(isoquinoline ring), strong π···π stacking interactions can be observed. Besides, strong I···I interactions can be monitored and extends the 0-D Bi4 I4-16 cluster to a quasi-1-D chain. The smaller energy gap of 2.13 eV is led by these non-covalent interactions. Its infrared emission might be caused by strong charge transfer between anions and cations. Furthermore, the reversible thermochromic behavior with low chromotropic temperature of 80 ℃ can be observed, whose mechanism was discussed. 展开更多
关键词 ORGANIC-INORGANIC hybrid iodobismuthates PHOTOLUMINESCENCE THERMOCHROMISM
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Photoluminescence of SiV centers in CVD diamond particles with specific crystallographic planes
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作者 梅盈爽 陈成克 +3 位作者 蒋梅燕 李晓 阮银兰 胡晓君 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第1期470-477,共8页
We prepared the isolated micrometer-sized diamond particles without seeding on the substrate in hot filament chemical vapor deposition. The diamond particles with specific crystallographic planes and strong silicon-va... We prepared the isolated micrometer-sized diamond particles without seeding on the substrate in hot filament chemical vapor deposition. The diamond particles with specific crystallographic planes and strong silicon-vacancy(SiV) photoluminescence(PL) have been prepared by adjusting the growth pressure. As the growth pressure increases from 2.5 to 3.5 kPa,the diamond particles transit from composite planes of {100} and {111} to only smooth {111} planes. The {111}-faceted diamond particles present better crystal quality and stronger normalized intensity of SiV PL with a narrower bandwidth of 5 nm. Raman depth profiles show that the SiV centers are more likely to be formed on the near-surface areas of the diamond particles, which have poorer crystal quality and greater lattice stress than the inner areas. Complex lattice stress environment in the near-surface areas broadens the bandwidth of SiV PL peak. These results provide a feasible method to prepare diamond particles with specific crystallographic planes and stronger SiV PL. 展开更多
关键词 DIAMOND particle SIV center PHOTOLUMINESCENCE crystallographic PLANES
芳基吡咯衍生物的合成及其发光性质 预览
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作者 郜昱 刘国罡 +1 位作者 石建兵 董宇平 《影像科学与光化学》 CAS 2019年第2期93-106,共14页
本文通过Sonogashira偶联反应合成了一类含有苯甲酸甲酯基团的吡咯衍生物MB3PE2和MB3,其结构为典型的给体(D,吡咯)-受体(A,苯甲酸甲酯基)结构,该类结构表现为可调的荧光性质。通过系统研究它们在各个状态下的发光性质,阐明了结构与性能... 本文通过Sonogashira偶联反应合成了一类含有苯甲酸甲酯基团的吡咯衍生物MB3PE2和MB3,其结构为典型的给体(D,吡咯)-受体(A,苯甲酸甲酯基)结构,该类结构表现为可调的荧光性质。通过系统研究它们在各个状态下的发光性质,阐明了结构与性能的关系。实验结果表明,共轭基团的加入对D-A共轭结构的化合物发光性质影响明显,且不同状态下的影响程度显著不同。MB3PE2具有π-T-型D-A结构而MB3是T-型D-A结构。它们在溶液状态下都具有明显的溶剂效应,但是其溶液态的荧光量子产率明显不同,π-T-型D-A结构的MB3PE2是T-型MB3的2.6倍。该结果对设计溶液态下高量子效率的D-A荧光化合物具有一定的指导意义。 展开更多
关键词 溶剂效应 吡咯 光致发光 量子效率
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