聚噻吩在离子液体中的电化学合成研究

在 1 丁基 3 甲基咪唑六氟磷酸盐离子液体 (BMIM)PF6 中直接电化学合成制备了聚噻吩膜 .通过红外光谱 (FT IR)和扫描电子显微镜 (SEM)对聚噻吩膜的结构和形貌进行了表征 .利用紫外可见光谱 (UV Vis)、循环伏安法 (CV)和四探针法研究了聚噻吩膜的电子和电化学特性 .研究结果表明 ,在电位 1.7～ 1.9V(相对于Ag/AgCl) ,在(BMIM)PF6 中可以制备均匀的聚噻吩膜 ,其中 ,离子液体 (BMIM)PF6 既作为溶剂又作支持电解质 ;在离子液体中制备的聚噻吩膜具有良好的稳定性和充放电能力 ,聚噻吩膜的电导率在 0 .0 1～ 0 .1S/cm .     

非晶/结晶共混对聚合物光伏电池性能的影响

以局域规整聚（3-己基噻吩） （P3HT）制备了TiO₂/聚合物型双层结构光伏电池.利用稳态电流-电压测试和动态强度调制光电压谱,结合差热分析、吸收光谱和荧光光谱, 研究了非晶支化聚亚乙基亚胺（BPEI）作为P3HT膜层的添加成分对TiO₂/P3HT双层电池性能的影响.由于P3HT链的高结晶性,使得TiO₂/P3HT界面接触不好,导致电池性能差.当在P3HT中共混重量比W_BPEI/P3HT=1％—5％的BPEI时,电池性能得到显著改善;尤其是当W_BPEI/P3HT= 1％时,电池表现出近0.8V的开路电压和20μA/cm²的短路电流.结果表明BPEI对电池性能的影响不是源于P3HT-BPEI共混体系光学性能的变化,而主要是由于其改变了TiO₂/P3HT界面接触性能.BPEI对TiO₂/P3HT界面接触有两个相互竞争的影响,这取决于P3HT-BPEI共混体系的组成.一方面,通过降低P3HT的结晶度和增强与TiO₂表面的相互作用,改善P3HT链在TiO₂ 表面的附着;另一方面,当BPEI含量过高时,BPEI在TiO₂表面的附着量将增加,反而会阻碍P3HT与TiO₂表面的接触.良好的TiO₂/P3HT界面接触有利于提高激子的界面分离效率、光生电子的寿命和电池效率.本文结果有望为聚合物光伏电池性能的改善提供新的认识和方法. 关键词： 聚（3-己基噻吩） 二氧化钛 共轭聚合物 光伏电池     

低成本衬底上多晶硅薄膜电池的探索

在低成本、两种纯度的P^ 颗粒硅带衬底(SSP)上，采用RT化学气相沉积(CVD)技术制备了多晶硅薄膜电池。无论高纯硅粉还是低纯硅粉制备的SSP衬底杂质含量都很高且表面凹凸不平；采用4μm／min的沉积速率和钝化作用得到了高质量外延多晶硅薄膜。通过扩散工艺制成的多晶硅薄膜太阳电池的转换效率分别为6．25％(高纯硅粉制成的SSP衬底)和4．5％(低纯硅粉制成的SSP衬底)。     

热裂解活化硒对CIGS太阳电池开路电压的影响

考察了通过自主研发的高温热裂解辅助硒化装置所产生的高活性硒对CIGS薄膜结构和器件性能的影响.通过调节高温裂解系统的温度可以有效调节不同的硒活性.研究发现, 第一台阶HC-Se气氛可以提高CIGS薄膜表面的Ga含量, 使得CIGS薄膜内的Ga分布更加平缓, 进而提高CIGS薄膜表面禁带宽度.而且HC-Se气氛可以消除CIGS"两相分离"现象.两种因素的共同作用使得CIGS薄膜太阳电池的开路电压提高了34.6%.电池转换效率从6.02%提升至8.76%, 增长了45.5%.     

有机聚合物受体给体复合体薄膜光伏电池性能研究

提出了用一种新的有机物－聚合物复合体薄膜制备受体给体聚合物光伏电池的思路,用于克服由于激子或极化子扩散范围短而熄灭造成的电荷分离与传输效率低的缺陷.在采用对称N,N′-二苯并咪唑3,4,9,10-四羧酸二亚酰胺和聚(2,5-二十五烷氧基对－苯撑乙烯)(ROPPV)为原材料制备成复合体薄膜,对其电学、光学及用其制作的光伏电池的性能进行了讨论.结果显示了导电聚合物－有机物复合体可代表一类新的有机半导体材料用于制造光伏电池 关键词： 有机光伏电池 有机染料 共轭聚合物 异质结     

GaN基半导体在改变钙钛矿太阳能电池性能方面的理论分析

GaN基半导体在光电子、电子器件已具有重要应用,如何结合其良好的电学特性进行其他应用方面的理论或实验探索,是当前新的研究课题.本文利用SCAPS-1D软件从理论上计算了GaN在FTO/GaN/(FAPbI₃)_0.85(MAPbBr₃)_0.15/HTL电池结构中电子传输的理论机制.结果表明,引入GaN后,电池的开路电压,转换效率明显提高.通过进一步分析准费米能级分裂、界面电场、界面复合率、耗尽层厚度等因素的变化规律,分析了GaN的厚度和掺杂浓度对电池开路电压等器件参数的影响,并从GaN作为电子传输层的物理机制方面进行了讨论.     

缓冲层提高有机聚合物光伏电池性能研究

在分析有机聚合物复合体光伏电池机理及等效电路模型基础上,研究了界面旋涂缓冲层对聚合物给体/受体复合体结构光伏器件性能的影响.制备了基于P3HT/PCBM的给体 受体复合体薄膜有机光伏电池,并分别在有机活性层和ITO基底之间以及有机活性层和电极之间插入TFB和F8BT缓冲层.实验证明：在ITO和活性层之间旋涂TFB作为阳极缓冲层,可增加有机聚合物光伏器件的短路电流,在活性层和电极之间插入F8BT作为阴极缓冲层,可增大光伏器件的开路电压,提高器件的转换效率.     

基于咔唑和噻吩的两种聚合物的电化学合成

利用斯蒂尔偶联反应合成了两种基于咔唑和噻吩的有机共轭单体,通过电化学方法聚合成导电聚合物,并对其进行了结构表征和光电性能研究. 核磁共振¹H谱和¹³C谱验证了单体与理论结构一致,红外测试验证了电化学聚合位点为噻吩的α位. 光滑、均质且分布小孔的表面形貌有利于提高聚合物的电导率和电子传输性能. 在-0.1 V到1.2 V电压范围内,两种聚合物膜都表现出良好的电致变色特性. 循环伏安法和热重表明,相比于聚合物P1,共平面性更好的聚合物P2的电化学和热稳定性更优.     

一种侧链共轭聚噻吩衍生物薄膜的三阶非线性光学响应

合成了一种侧链共轭的聚噻吩衍生物聚3-（5′辛基-噻吩乙烯基）噻吩（POTVTh）,并通过溶液旋涂制备了聚合物薄膜.吸收光谱显示该聚合物薄膜具有较小的禁带宽度和宽的光谱响应.采用Z扫描技术在800 nm下用飞秒激光器研究了该聚合物薄膜的三阶非线性光学特性,非线性吸收系数为5.63×10^-7cm/W,非线性折射率为-6.38×10^-11 cm²/W,三阶非线性极化率为4.21×10^-9esu,比侧链未共轭的 关键词： 聚噻吩衍生物 侧链共轭 三阶非线性极化率 非线性折射率     

氧化锌掺铝绒面薄膜在有机光伏电池中的应用

目前有机光伏电池的吸光活性层电学传输特性和光学吸收特性的不匹配是制约其能量转换效率提升的主要原因之一. 通过陷光结构对入射光进行调控, 提高电池对光的约束和俘获能力从而达到“电学薄”和“光学厚”的等效作用, 是解 决有机光伏电池电学和光学不匹配的有效手段. 本文采用湿法刻蚀技术获得了系列时间梯度的绒面氧化锌掺铝薄膜, 并将其作为有机光伏电池的入射陷光电极, 显著增强了电池的光学吸收. 研究发现, 当使用浓度0.5%的稀HCL腐蚀30 s后的氧化锌掺铝薄膜作为入射电极后, 电池的光电性能和效率显著增强. 基于此绒面电极电池的电流密度比平面结构的电池提高了8.17%, 效率改善了11.29%. 通过对绒面电极表面的修饰处理, 实现了电极与光活性层之间良好的界面接触, 从而减小了对电池的开路电压和填充因子的影响.     

Electrodeposition of zinc oxide/tetrasulfonated copper phthalocyanine hybrid thin film for dye-sensitized solar cell application

Hybrid film of zinc oxide (ZnO) and tetrasulfonated copper phthalocyanine (TSPcCu) was grown on an indium tin oxide (ITO) glass by one-step cathodic electrodeposition from aqueous mixtures of Zn(NO₃)₂, TSPcCu and KCl. The addition of TSPcCu strongly influences the morphology and crystallographic orientation of the ZnO. The nanosheets stack of ZnO leads to a porous surface structure which is advantageous to further adsorb organic dyes. The photovoltaic properties were investigated by assembling the DSSC device based on both the only ZnO film and the ZnO/TSPcCu hybrid films. Photoelectrochemical analysis revealed that the optimized DSSC device with TSPcCu represented a more than three-fold improvement in power conversion efficiency than the device without TSPcCu. The DSSC based on ZnO/TSPcCu hybrid films demonstrates an open circuit voltage of 0.308 V, a short circuit current of 90 μA cm⁻², a fill factor of 0.26, and a power conversion efficiency of 0.14%.     

Effects of rubrene mixing on the electronic structures of donor/acceptor interface in organic photovoltaic device

Rubrene mixing has been shown to be an effect mean for enhancing both the open circuit voltage (Voc) and the short-circuit current (Jsc) of copper-phthalocyanine (CuPc)/fullerene (C₆₀) based solar cell. While the increase in Jsc can be readily explained by the additional rubrene absorption and the introduction of a bulk heterojunction; causes for Voc increase are still not clear. The energy offset between the highest occupied molecular orbital (HOMO) level of donor and the lowest unoccupied molecular orbital (LUMO) level of acceptor (HOMO_D-LUMO_A) at the CuPc/C₆₀ interface was found to increase substantially upon rubrene mixing in either side of the interface. As the HOMO_D-LUMO_A is generally considered to limit the Voc, its increase agrees well with the device results. Energy level bending and associated built-in electric fields were also observed and their possible implications to device performance are discussed.     

非晶硅锗电池性能的调控研究

采用射频等离子体增强化学气相沉积技术, 研究了非晶硅锗薄膜太阳电池. 针对非晶硅锗薄膜材料的本身特性, 通过调控硅锗合金中硅锗的比例, 实现了对硅锗薄膜太阳电池中开路电压和短路电流密度的分别控制. 借助于本征层硅锗材料帯隙梯度的设计, 获得了可有效用于多结叠层电池中的非晶硅锗电池. 关键词： 非晶硅锗薄膜太阳电池 短路电流密度 开路电压 带隙梯度     

Magnetic characteristics of thin Ni films electrodeposited on n-Si(1 1 1)

The nanocrystalline Ni films were grown on n-Si(1 1 1) substrate by pulsed electrodeposition in non-aqueous NiCl₂ + methanol solution. The frequency of potential pulse was modulated during the deposition of Ni onto Si substrates. When the frequency varies from 20 to 900 Hz, the average size of Ni nanocrystallites varied in the ranges from 48 to 130 nm. In these cases, all Ni films have grown through a three-dimensional instantaneous nucleation followed by diffusion-limited growth. From X-ray diffraction measurement, it has been found that Ni(1 1 1) grows preferentially on the Si(1 1 1) substrates. The magnetic hysteresis loops for as-deposited films were measured by using VSM. As the angle θ between film plane and applied magnetic field varies from 0 to 90, the coercivity (H_c) and squareness (S) obtained from the magnetic hysteresis loops showed an opposite behavior. With the increase in θ, H_c increased but S decreased near linearly. We have also investigated the variation of H_c as a function of Ni nanocrystallite’s size. From VSM measurement, we could observe that the coercivities for the magnetic field applied perpendicular and parallel to the film plane increase up to the average size of 86 nm but begin to decrease over this size.     

Enhanced optical absorption by Ag nanoparticles in a thin film Si solar cell

Thin film solar cells have the potential to significantly reduce the cost of photovoltaics. Light trapping is crucial to such a thin film silicon solar cell because of a low absorption coefficient due to its indirect band gap. In this paper, we investigate the suitability of surface plasmon resonance Ag nanoparticles for enhancing optical absorption in the thin film solar cell. For evaluating the transmittance capability of Ag nanoparticles and the conventional antireflection film, an enhanced transmittance factor is introduced. We find that under the solar spectrum AM1.5, the transmittance of Ag nanoparticles with radius over 160 nm is equivalent to that of conventional textured antireflection film, and its effect is better than that of the planar antireflection film. The influence of the surrounding medium is also discussed.     

Enhanced photovoltaic performance of solution-processed Sb2Se3 thin film solar cells by optimizing device structure

Thin-film solar cells have attracted worldwide attention due to their high efficiency and low cost. Antimony selenide (Sb₂Se₃) is a promising light absorption material candidate for thin-film solar cells due to its suitable band gap, abundance, low toxicity, and high chemical stability. Herein, we fabricate an Sb₂Se₃ thin film solar cell using a simple hydrazine solution process. By controlling the thickness of the photoactive layer and inserting a poly(3-hexylthiophene) hole-transporting layer, an Sb₂Se₃ solar cell with a power conversion efficiency of 2.45% was achieved.     

激光电致发光薄膜屏的高压脉冲电源

这种脉冲电源的设计不同于市售的脉冲电源，它具有电路结构简单，体积小，电压高，正负脉冲叠加，具有快的上升时间，稳定性能好等特点。最适合于做为电致发光屏和电致发光薄膜屏的激发源。是测量发光屏的强度、寿命、时间分辨光谱的非常适用的激发源。     

A new analytical model of high voltage silicon on insulator （SOI） thin film devices

A new analytical model of high voltage silicon on insulator (SOI) thin film devices is proposed, and a formula of silicon critical electric field is derived as a function of silicon film thickness by solving a 2D Poisson equation from an effective ionization rate, with a threshold energy taken into account for electron multiplying. Unlike a conventional silicon critical electric field that is constant and independent of silicon film thickness, the proposed silicon critical electric field increases sharply with silicon film thickness decreasing especially in the case of thin films, and can come to 141V/μm at a film thickness of 0.1μm which is much larger than the normal value of about 30V/μm. From the proposed formula of silicon critical electric field, the expressions of dielectric layer electric field and vertical breakdown voltage (V_B,V) are obtained. Based on the model, an ultra thin film can be used to enhance dielectric layer electric field and so increase vertical breakdown voltage for SOI devices because of its high silicon critical electric field, and with a dielectric layer thickness of 2μm the vertical breakdown voltages reach 852 and 300V for the silicon film thicknesses of 0.1 and 5μm, respectively. In addition, a relation between dielectric layer thickness and silicon film thickness is obtained, indicating a minimum vertical breakdown voltage that should be avoided when an SOI device is designed. 2D simulated results and some experimental results are in good agreement with analytical results.     

瞬态光电流对有机薄膜光伏器件中肖特基接触的研究

制备了结构为氧化铟锡(ITO)/有机半导体/金属的有机薄膜光伏器件,电流--电压曲线显示其具有整流特性但有机半导体和电极间肖特基接触的内建电场方向很难判定.为了研究有机半导体和电极的肖特基接触特性,分别制备了结构为ITO/有机绝缘层/有机半导体/金属和ITO/有机半导体/有机绝缘层/金属的器件,通过调制激光照射下器件的瞬态光电流方向可容易判断有机半导体和电极间肖特基接触的内建电场方向,外加偏压下瞬态光电流的强度变化进一步证实了判断的正确性.     

Pb(Zr0.3Ti0.7)O3铁电薄膜激光感生电压效应

采用脉冲激光沉积(PLD)技术在LaSrAlTaO₃(LSATO),LaAlO₃(LAO)和SrTiO₃(STO)的单晶倾斜衬底上成功制备了Pb(Zr_0.3Ti_0.7)O₃(PZT)薄膜,在三种倾斜衬底上生长的PZT薄膜中都首次发现了LIV效应.对PZT/LSATO薄膜在a,c轴两种不同取向择优生长下的LIV效应做了研究,发现在薄膜c轴取向择优生长 关键词： 激光感生电压效应 铁电薄膜 薄膜生长取向 原子层热电堆