29种天然染料敏化的太阳电池的性能研究

采用超声波萃取法从29种天然植物中提取染料, 测试天然染料的紫外-可见光(UV-vis)吸收光谱,探讨天然染料所 含的色素种类。采用水热法制备了TiO₂薄膜电极,用所提取的29种天然染料敏化TiO₂光 电极并将其组装成染料敏化太阳电池(DSSCs)。测试天然染料敏化的DSSCs 的光电性能结果显示,天然染料敏化的DSSCs的开路 电压Voc为0.46~0.64 V,短路电流I_sc为0.07~3.61mA· cm－2,其中山竹皮敏 化的DSSCs光电性能最佳,对应的I_sc和光电转换 效率η分 别为3.61mA·cm－2和2.13%。从天然 染料中挑选出7种不同吸收波段色素的染料进行协同敏化,UV-vis吸收光谱测试结 果显示混合染料的吸收峰一般有微小偏移。光电性能测试结果表明,协同敏化后的DSSCs的 性能一般都介于天然染料单独敏 化的两个DSSCs的性能之间,其中山竹皮和芥蓝协同敏化的DSSCs的η最高,为1.70%。对实验结果进行深入分析,探讨提高天然染料 敏化的DSSCs光电性能的途径。     

叶绿素与4种天然染料共敏化太阳电池的光电化学性能研究

利用紫外-可见吸收光谱 对提取的叶绿素和4种天然染料(茶多酚、靛蓝、 红花黄、栀子黄)以及叶绿素与4种染料的共敏化 进行比较。通过电化学方法,研 究单一染料和共敏化染料的氧化还原电位。结果表明,杨树叶子中叶绿素最佳的提取 工艺条件为:提取料液比1∶50,提取温度60 ℃,提取时间3.5h。叶绿素与4种天然染料共敏化后不仅拓宽光谱吸 收波长范围,而且染 料激发态氧化电位与TiO₂导带能级相匹配。其中叶绿素与栀子黄染料共敏化后,光电化学 性能最好。在太阳光模拟下,叶绿素与栀子黄对电池进行共敏化后光电转换 效率提高到0.67%,是叶绿素染料单独敏化的2.91倍。     

低温处理的TiO2纳米颗粒薄膜作为缓冲层的有机光伏电池

通过溶胶凝胶法(sol-gel)合成了TiO₂纳米颗 粒(NPs),制备了结构为 ITO/PEDOT:PSS/P3HT:PCBM/TiO₂/Al的有机太阳能电池(OSC)器件。通过优化阴极缓冲 层TiO₂NPs的 热处理温度,考察了温度以及溶剂对TiO₂NPs薄膜的光学性能、形貌结构和电学 性能的影响,并研究了其对OSC性能的影响及作用机理。实验发现,TiO₂NPs处理温度 为80℃时,器件 的效率达到了2.52%。相对于参比器件,器件的光电转换效率(PCE) 、填充因子(FF)分别提高了60%、64.7%。     

酰化紫薯色素敏化太阳能电池的性能研究

针对花青素类染料紫薯色素作为染料敏化太阳能 电池(DSCs)中敏化剂的不足,采用咖啡酸为酰化剂进行化 学修饰。研究了反应时间、反应温度以及花青素与咖啡酸的物料比对酰化紫薯色素的影响, 进行正交试验 找出了最佳实验方案,并对最佳条件下得到的酰化紫薯色素进行相关性能测试。实验结果表 明,当物料比为 0.1 g/20mL、温度为60℃和反应时间为20min时,制备得到的酰化紫薯色素的紫外光谱性能最好;酰化后紫薯色 素 的吸光强度、吸附量和稳定性均有增强,并且禁带宽度均减小。在太阳光模拟下,分别利用 酰化前后的紫 薯色素组装DSCs,酰化后DSCs的光-电转换效率提高了21%。     

非稀土红色荧光粉Mn4+:Li2TiO3发光特性研究

利用高温固相法成功合成了非稀土类红色荧光粉 Mn⁴⁺:Li₂TiO₃,并对所制得的样品进行X射线衍射(XRD)、吸收谱和荧光发射谱等 表征。在波长为475nm的LED蓝光照射时,获得了最大强度位于〖J P 〗682nm波长处的红色荧光,量 子效率约为10%,其对应Mn⁴⁺自旋²Eg→⁴A 2g。计 算了晶体场强度因子Dq和Racah参数B、C,并据此分析了Mn⁴⁺在Li₂TiO₃中的电 子云重排效应。通 过改变掺杂浓度,分析了Mn⁴⁺掺杂在Li₂TiO₃中的浓度淬灭效 应。最后进行了LED白光性能 测试。     

采用Taguchi方法优化一种带外延层的PPD工艺参数

结合水热法和阳极氧化法合成了Sb₂S₃/TiO₂纳米管异质结阵列,采用场发射扫描电子显微镜、X射线衍射谱表征了异质结阵列的形貌和晶体结构。暗态下的电流-电压曲线表明Sb₂S₃/TiO₂纳米管异质结阵列具有整流效应。相比于纯的TiO2纳米管阵列,Sb₂S₃/TiO₂纳米管异质结阵列的光电性能有了显著的提升:在AM 1.5标准光强作用下,光电转换效率从0.07%增长到0.40%,表面光电压响应范围从紫外光区拓宽至可见光区。结合表面光电压谱和相位谱,分析了Sb₂S₃/TiO₂纳米管异质结阵列中光生载流子的分离和传输性能。 更多还原     

TiO2表面预处理对钙钛矿太阳电池性能的影响

采用一步法制作了基于 n-i-p结构的钙钛矿太阳电池。为了提高钙钛矿活性层以及TiO₂与钙钛矿活性层接触面的质量,用 MAI、MABr和PbI₂溶液对TiO₂层进行预处理,研究了预处理对电池性能的影响。结果显示对TiO₂进行预处理能够改善钙钛矿活性层薄膜的质量并提升钙钛矿太阳电池的性能。通过溶液预处理,太阳电池的能量转换效率和器件稳定性有显著提高,同时滞后效应明显减弱。     

染料敏化纳米晶TiO2太阳能电池

介绍了染料敏化纳米晶TiO2太阳能电池的结构,工作原理,技术指标以及TiO2纳米膜的制备方法.阐述了敏化纳米晶太阳能电池相比于硅太阳电池的低成本及优于其它光电化学电池的关键技术.讨论了影响NPC电池总的光电转换效率的因素,并对有机染料和无机染料光敏化剂的选择及染料的敏化问题进行了论述,在此基础上提出了将其商业化的一些值得深入研究和需要解决的问题.     

三元合金CdSexTe1-x量子点敏化太阳能电池

为了获得高光电转化效率的量子点敏化太阳能电池,我们制备了水相合金量子点CdSexTe1-x,通过直接吸附方法组装了量子点敏化太阳能电池,比较不同Se:Te比例下CdSexTe1-x电池的性能变化;当Se:Te=2:3时,CdSexTe1-x敏化太阳能电池各种性能最佳,其光电转换效率可达2.47%。相比于同条件制备的水相CdSe和CdTe量子点敏化太阳能电池转换效率分别提升了90% 和70%。进一步改善CdSexTe1-x量子点表面修饰,抑制电池暗电流,在使用液态多硫电解液的环境下,获得了填充因子为72.7%的CdSexTe1-x量子点敏化电池。     

层状下转换材料KLa0.90Nb2O7:Eu3+的制备和发光性质研究

利用高温固相反应法,制备了具有层状钙钛矿结构 的下转换材料KLa0.90Nb₂O₇:Eu³⁺。采用X射线衍射(XRD)、 扫描电子显微镜(SEM)、紫外可见吸收(UV-Vis)和荧光分光光度计分别对产物的晶体结构 、微观形貌和光致发光(PL)性质进行 了检测。XRD结果表明,产物KLa0.90Nb₂O₇:Eu³⁺属正交晶系的钙钛矿结构 晶体,产物中有EuNbO₄的杂相存在。煅烧温度和 时间分别为1150℃、12h是合成KLa0.90Nb₂O₇:Eu³⁺的适 宜条件。PL谱显示,在363nm波长激发下,KLa0.90Nb₂O₇:Eu³⁺有波长为578nm, 592和614nm 3个发光峰。KLa0.90Nb₂O₇:Eu³⁺因层状结构在制备薄膜 器件时具有优势,有望在光伏器件尤其是Si基太阳能电池中增加光电转换效率并且延长器 件使用寿命。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks