PEDOT:PSS薄膜的山梨醇掺杂对光电池性能的影响

采用共混-旋涂技术在ITO导电玻璃上制备出经山梨醇掺杂的PEDOT:PSS导电膜,将所制得的薄膜作为空穴传输层用于有机太阳能电池研究.通过对比分析掺杂前后光电池暗电流曲线与光电流曲线的变化,考察了山梨醇掺杂对器件光伏性能的影响,并就其中的影响机理进行了讨论分析.结果表明,山梨醇的加入,可以明显提高光电池的短路电流,填充因子以及能量转换效率.较未掺杂器件,8wt %山梨醇掺杂条件下,器件短路电流由8.82 mA/cm²增加至11.27 mA/cm²,FF由0.43 关键词： PEDOT:PSS薄膜 山梨醇 有机太阳能电池 性能     

基于氧化石墨烯空穴传输层的钙钛矿太阳能电池

采用溶液旋涂法在平面异质结型钙钛矿电池中引入氧化石墨烯(Graphene oxide,GO),制备了GO、GO∶(PEDOT:PSS)复合薄膜和GO/PEDOT∶PSS双层薄膜作为空穴传输层的电池,其光电转换效率分别为1.86%、7.35%、7.69%,基于PEDOT∶PSS空穴传输层的对照电池的效率为7.38%.主要原因是GO具有绝缘性,作为阳极界面层时,随着GO薄膜厚度增加,器件的串联电阻增大,从而降低了电池的短路电流和效率.为提高GO导电性,并改善其功函数,将GO氨化改性后与PEDOT:PSS组合构成双空穴传输层,所得电池取得了7.69%的较高效率,表明该方式是GO用于钙钛矿电池空穴传输层的有效途径.     

PTCDI-C8作为阴极修饰层提高钙钛矿太阳能电池的性能

采用N,N'-二正辛烷基-3,4,9,10-苝四甲酰二亚胺（PTCDI-C₈）对钙钛矿电池电子传输层（PCBM）进行界面修饰以减少PCBM与Al电极之间的漏电流,提高阴极的电子收集效率。通过调节PTCDI-C₈薄膜的厚度优化界面接触和电子传输性能。实验结果表明：当PTCDI-C₈薄膜的厚度为20 nm时得到的器件性能最优。光电转换效率（PCE）由5.26%提高到了8.65%,开路电压（V_oc）为0.92 V,短路电流（J_sc）为15.68 mA/cm²,填充因子（FF）为60%。PTCDI-C₈能够有效阻挡空穴向阴极传输,同时PTCDI-C₈具有较高的电子迁移率以及较高的稳定性,在增加电子传输的同时,可减少环境对PCBM的侵蚀,提高了器件的稳定性。     

阳极界面修饰对钙钛矿太阳能电池性能的影响

采用在聚(3,4-乙撑二氧噻吩)∶聚苯乙烯磺酸(Poly(3,4-ethylenedioxythiophene)∶Poly(styrenesulfonate),PEDOT∶PSS)阳极界面层上直接旋涂二甲基亚砜(Dimethyl Sulfoxide,DMSO)的方法,对PEDOT∶PSS薄膜进行修饰,以提高所制得的钙钛矿太阳能电池器件性能.在5000rpm转速条件下旋涂DMSO后,器件的能量转换效率达到11.43%,与PEDOT∶PSS阳极界面层未做任何修饰的器件相比,效率提高了29.15%.测试表征了修饰前后PEDOT∶PSS薄膜的透光性、表面形貌、电导率、器件的外量子效率曲线以及器件在光照和暗态下的J-V特性曲线,分析了器件性能提高的原因.结果表明:经过修饰的PEDOT∶PSS薄膜导电性显著增强,从而更加有利于器件阳极对空穴的抽取和收集;较未修饰时,器件的短路电流密度得到了大幅度提升,进而使得器件获得更高的能量转换效率.     

掺杂PEDOT ∶PSS对聚合物太阳能电池性能影响的研究

研究了掺杂后poly(3,4-ethylene dioxythiophene):poly(styrenesulphonic acid)(PEDOT ∶PSS)电导率的变化以及掺杂PEDOT ∶PSS薄膜对聚合物太阳能电池器件性能的影响. 实验发现,向PEDOT ∶PSS中掺入极性溶剂二甲基亚砜(DMSO)明显提高了薄膜的电导率,掺杂后的电导率最大值达到1.25 S/cm,比未掺杂时提高了3个数量级. 将掺杂的PEDOT ∶PSS薄膜作为缓冲层应用于聚合物电池 (ITO/PEDOT ∶PSS/P3HT ∶PCBM/LiF/Al) 中,发现高电导率的PEDOT ∶PSS降低了器件的串联电阻,增加了器件的短路电流,从而提高了器件的性能. 最好的聚合物太阳能电池在100 mW/cm²的光照下,开路电压(V_oc)为0.63 V,短路电流密度(J_sc)为11.09 mA·cm^-2,填充因子(FF)为63.7%,能量转换效率(η)达到4.45%. 关键词： PEDOT ∶PSS 电导率 聚合物太阳能电池 能量转换效率     

平面异质结有机-无机杂化钙钛矿太阳电池研究进展

高效低成本太阳电池的研发是太阳能光伏技术大规模推广应用的关键. 近年来兴起的有机- 无机杂化钙钛矿(以下简称钙钛矿)太阳电池因具有光电能量转换效率高、制备工艺简单等优点, 引起了学术界和产业界的广泛关注, 具有广阔的发展前景. 其中平面异质结钙钛矿太阳电池因具有结构简单, 可低温制备等诸多优点, 成为目前研究的一个重要方向. 平面异质结钙钛矿太阳电池分为n-i-p型和p-i-n型两种结构. 其中钙钛矿分别与电子传输层和空穴传输层形成两个界面, 在这两个界面上实现电子和空穴的快速分离. 电子传输层和空穴传输层分别为电子和空穴提供了独立的输运通道. 平面异质结结构有利于钙钛矿太阳电池中电子和空穴的分离、传输和收集. 此外, 该结构不需要高温烧结的多孔结构氧化物骨架, 扩大了电子和空穴传输材料的选择范围. 可以根据钙钛矿材料的能带分布及载流子传输特性, 来选择能级和载流子传输速率更为匹配的传输材料. 本文对钙钛矿的材料特性, 平面异质结结构的由来及发展进行了简要的概述. 其中重点介绍了平面异质结钙钛矿太阳电池的结构特征、工作机理、钙钛矿/电荷传输层的界面特性, 以及电池性能的优化, 包括钙钛矿薄膜制备、空穴和电子传输层的优化等. 最后对钙钛矿电池的发展前景及存在问题进行了阐述, 为今后高效、稳定钙钛矿太阳电池的研究提供参考.     

一种红光螯合电磷光聚合物光电性能的研究

研究了螯合电磷光聚合物PFBtpIrm的光致发光、电化学和电致发光特性,并通过优化器件结构提高聚合物的电致发光性能.发现在聚合物中加入PBD使发光效率降低;而加入PVK空穴传输层后,由于能量有效地转移到电磷光聚合物中,器件性能提高.基于器件ITO/PEDOT/PVK/ PFBtpIrm5/Ba/Al,在电流密度为10.0mA/cm²时,最大外量子效率为4.25%,饱和红光的色坐标为(0.69,0.29). 关键词： 电致磷光 聚合物发光二极管 电子传输材料 空穴传输材料     

NiO_x作为空穴传输层对有机太阳能电池光吸收的影响

基于多层膜系模型的传输矩阵方法、麦克斯韦方程和光子吸收方程,研究了NiOx作为替代3,4-乙撑二氧噻吩:聚苯乙烯磺酸盐(PEDOT:PSS)的空穴传输材料对聚3-己噻吩(P3HT)和富勒烯衍生物([6,6]-phenyl-C61-butyric acid methyl ester,PC61BM)共混体异质结有机太阳能电池器件内部光电场分布和光吸收特性的影响.分别制备了以NiOx和PEDOT:PSS为空穴传输层,P3HT:PCBM为活性层的有机太阳能电池,并通过数值模拟的方法比较了NiOx和PEDOT:PSS两种空穴传输材料对器件光伏特性的影响.结果表明:10 nm的NiOx空穴传输层器件比40 nm的PEDOT:PSS器件获得了更大的短路电流和填充因子,并具有更高的能量转化效率.     

钙钛矿太阳电池中的缓冲层研究进展

基于钙钛矿材料优异的光电特性,钙钛矿太阳电池的转换效率迅速提高.但制约钙钛矿太阳电池性能的因素依然存在,例如:界面问题、稳定性问题等.通过在载流子传输层/电极及载流子传输层/光吸收层之间引入能带结构合适的缓冲层,可有效改善界面间的能带失配、载流子复合及化学反应等问题,进而提高钙钛矿电池中的电荷分离及收集效率,实现界面及稳定性问题的有效改善.本文总结了当前钙钛矿太阳电池中引入的缓冲层材料,全面分析了不同缓冲层材料钝化空穴传输层/阳极、电子传输层/阴极、空穴传输层/吸收层及电子传输层/吸收层间界面的机理,对比了不同缓冲层材料对电池性能的影响,总结了缓冲层材料在钙钛矿电池中的作用,最后指出了钙钛矿电池中各界面缓冲层材料的研究趋势及发展方向.     

双添加剂处理电子传输层富勒烯衍生物[6,6]-苯基-C61丁酸甲酯对钙钛矿太阳能电池性能的影响

有机无机复合钙钛矿材料被证明是非常出色的光伏材料,目前主要通过优化钙钛矿材料的结晶和形貌来提高钙钛矿太阳能电池的效率.而对于电荷传输层,特别是p-i-n结构中电子传输层的研究相对较少.因此,本文制备了结构为ITO/PEDOT:PSS/CH3NH3Pb I3/PCBM/Al的钙钛矿太阳能电池通过在电子传输层富勒烯衍生物[6,6]-苯基-C61丁酸甲酯(PCBM)中添加聚苯乙烯(PS)和1,8-二碘辛烷(DIO)使得钙钛矿太阳能电池的光电转换效率从10.8%提升到了12.5%.分析了性能提高的原因主要是:1)添加剂PS的加入提升了PCBM的黏度,从而形成了质量更高、更平滑的膜层,这有利于抑制电子和空穴在钙钛矿层和电子传输层之间的复合;2)添加剂DIO的加入改善了电子传输层的形貌,有利于电荷的分离、传输和收集.研究结果表明用成本较低的添加剂处理可以改善电子传输层的形貌和膜层的质量达到了改善电荷传输特性的效果提升了钙钛矿太阳能电池的效率为提升钙钛矿太阳能电池性能提供了一条可行的路径.     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.     

A stereo matching algorithm using multi-peak candidate matches and geometric constraints

Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.