有机共混结构叠层太阳电池的研究进展

有机太阳电池由于质轻、价廉、柔性,受到人们的广泛关注.单个有机材料只能吸收部分太阳光,叠层结构的太阳电池将不同吸收带隙的有机材料通过中间层连接起来,既能充分吸收太阳光,又能提高太阳电池的开路电压或短路电流.本文综述了近年来有机共混结构叠层太阳电池的研究进展,介绍了各种叠层有机太阳电池的结构、原理及性能,阐述了国内外有机叠层太阳电池研究的现状及存在问题,为高性能有机太阳电池的研究提供有价值的参考.     

聚(2-甲氧基-5-辛氧基)对苯乙炔/TiO2纳米复合材料的光物理性能研究

通过原位强碱诱导下的脱氯化氢缩合聚合法制备了一系列不同纳米TiO2含量的聚(2-甲氧基-5-辛氧基)对苯乙炔/纳米二氧化钛(PMOCOPV/TiO2)光电复合材料。红外光谱和拉曼光谱证实了在纳米TiO2表面的包覆层为PMOCOPV。紫外-可见吸收光谱表明随着TiO2含量的增加PMOCOPV/TiO2纳米复合材料的吸收强度提高。高分辨透射电镜观察发现PMOCOPV/TiO2是具有核-壳结构的纳米复合粒子,直径约30 nm,其中PMOCOPV包覆层的厚度约为8~10 nm。荧光光谱研究表明,PMOCOPV/TiO2纳米复合材料的最大发射波长随着TiO2含量的增加发生红移,荧光寿命约为1 ns,且随着TiO2含量的增加荧光强度和荧光寿命得到显著提高,并通过PMOCOPV/TiO2纳米复合材料中的激子离化和电荷传输过程以及复合材料中的电势能级探讨了PMOCOPV/TiO2的荧光量子效率和荧光强度增加的机理。     

聚(2,5－二丁氧基对苯乙炔)电致发光性能的研究

本文对以聚(2,5-二丁氧基对苯乙炔)为发光层的聚合物电致发光二极管的电致发光性能和影响其性能的因素进行了研究。其发光峰值波长为590um,起亮电压为12V,最大亮度可达112cd/m2.热处理温度和时间影响其发光强度和峰值波长,一般以200℃,真空处理3.5h为宜。还原气氛(N2+H2)下的热处理有利于电致发光性能的提高。器件在空气中具有一定的使用寿命。其量子效率可达0.16%光子/电子。并研究了器件制备工艺对性能的影响,初步探讨了聚合物电致发光机理。     

聚(2,5-二丁氧基)对苯乙炔/多壁碳纳米管复合材料的制备和性能研究

通过原位聚合法制备了聚（2,5-二丁氧基）对苯乙炔/多壁碳纳米管（PDBOPV/MWCNTs）复合材料.红外光谱和拉曼光谱证实了在MWCNTs表面的包覆层为PDBOPV.高分辨透射电子显微镜观察发现,PDBOPV/MWCNTs复合材料直径为35—45 nm,其中PDBOPV包覆层厚度约为15 nm.紫外—可见吸收光谱表明随着MWCNTs含量的增加,PDBOPV/MWCNTs的吸收发生红移且强度提高.荧光光谱研究表明随着MWCNTs含量的增加,PDBOPV/MWCNTs的最大发射波长发生蓝移且强度减小,MWCNTs与PDBOPV之间形成了光致电子转移体系,使得π电子离域程度增加,并且导致荧光量子效率降低.根据E_g与入射光子能量hν的关系,拟合了PDBOPV/MWCNTs薄膜的光学禁带宽度,发现随着MWCNTs的增加,E_g逐步减小.采用简并四波混频方法测试它们的三阶非线性极化率χ^（3）,结果发现随着MWCNTs含量的增加,PDBOPV/MWCNTs复合体的非线性光学响应逐渐增强,这说明PDBOPV与MWCNTs之间形成了分子间光致电子转移体系,产生了复杂的分子间π-π电子非线性运动. 关键词： 聚（2 5-二丁氧基）对苯乙炔 多壁碳纳米管 复合材料 光致发光     

聚对苯乙炔的能带结构和关联能计算

在考虑电子-电子相互作用情况下,对基态非简并聚合物聚对苯乙炔（PPV）的长程关联能进行了理论计算,并用长程关联能对带隙进行修正,最后讨论了长程关联能对带隙的影响。在对PPV链的计算中发现,长程关联能先会随着链长N的增加而减小,但当链长大于10后长程关联能会达到饱和。在链长为20个单元的PPV计算中,长程关联能的修正会降低由Hartree-Fock(HF)方法所得的能隙宽度。修正后的能隙宽度能很好的接近实验结果。     

聚对苯乙炔的能带结构和关联能计算

在考虑电子-电子相互作用情况下,对基态非简并聚合物聚对苯乙炔(PPV)的长程关联能进行了理论计算,并用长程关联能对带隙进行修正,最后讨论了长程关联能对带隙的影响.在对PPV链的计算中发现,长程关联能先会随着链长N的增加而减小,但当链长大于10个PPV单元后,长程关联能会达到饱和.与由Hartree-Fock(HF)方法所得的能隙宽度比.长程关联能的修正会使得能隙降低,这种修正后的能隙宽度与实验结果一致.     

采用热处理方法提高MEH-PPV单层聚合物有机发光二极管发光性能的研究

对以MEH－PPV为发光层的单层聚合物有机发光二极管（OLED）器件在最佳条件下进行真空热处理，并用金相显微镜观察施加电压后器件的阴极表面形貌。发现处理后的器件阴极表面的气泡及黑斑明显减少。器件的发光性能显著提高。与未经处理的器件相比，最大相对发光强度提高了一个数量级、启亮电压降低了2．0V，半寿命提高了12．7倍。初步分析表明热处理方法提高器件发光性能的主要原因在于有效地减少了器件在工作过程中由于焦耳热产生的某些气体，从而减少阴极表面气泡及黑斑的出现，另一方面，热处理方法也增强了有机发光层与阴极接触界面的结合力，提高电子注入水平。     

聚(2-甲氧基-5-辛氧基)对苯乙炔/Y_2O_3:Eu~(3+)纳米复合材料的光致电子转移效应

采用原位脱氯化氢缩合聚合法制备了聚(2-甲氧基-5-辛氧基)对苯乙炔/Y_2O_3:E~(3+)(PMOCOPV/Y_2 O_3:Eu~(3+))纳米复合材料。红外光谱证实了在Y_2O_3:Eu~(3+)表面的包覆层为PMOCOPV。紫外-可见吸收光谱表明与PMOCOPV相比,PMOCOPV/Y_2O_3:Eu~(3+)的最大吸收峰发生红移且强度提高。荧光光谱研究表明PMOCOPV/Y_2O_3:Eu~(3+)的最大发射波长发生红移且强度提高,荧光寿命得到增强,Y_2O_3:Eu~(3+)与PMOCOPV之间形成了光致电子转移体系,使得π电子离域程度增加,并且导致荧光量子效率提高。根据E_g与入射光子能量hv的关系,拟合了PMOCOPV/Y_2O_3:Eu~(3+)薄膜的光学禁带宽度,发现E_g减小。采用简并四波混频方法测试它们的三阶非线性极化率x~((3)),结果发现与PMOCOPV相比,PMOCOPV/Y_2O_3:Eu~(3+)纳米复合体的非线性光学响应逐渐增强,进一步说明PMOCOPV与Y_2O_3:Eu~(3+)之间形成了分子间光致电子转移体系,产生了复杂的分子间离域π电子非线性运动。     

新试剂3-对氟苯基-5-(2′-胂酸基苯偶氮)绕丹宁的合成及荧光法测定铋的研究

合成了新型荧光试剂 3 对氟苯基 5 (2′ 胂酸基苯偶氮 )绕丹宁 ,并并经元素分析、IR确证了其结构。研究了其荧光性质 ,发现在 pH 5 4时试剂与痕量铋 (Ⅲ )形成的螯合物可使试剂的荧光强度大大减弱 ,在λex/λem =30 5 / 4 0 7nm处有最大峰 ,其荧光猝灭值与铋的浓度在 0～ 0 0 2 5 μg·mL-1范围内呈线性关系 ,检出限达 1 2× 10 -10 g·mL-1。建立了一种荧光光度法测定痕量铋的新方法     

Magnetic Field-Effect on Photoluminescence of Poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) Nanoparticles in a Poly[vinyl butyral] Matrix

Abstract

In this work the magnetic field effects (MFE) on the photoluminescence of MEH-PPV film and nanoparticles were obtained using the MFE technique with continuous-wave photoexcitation. The analysis of the MFE dependence for the MEH-PPV film gave a HWHM (half-width at half maximum) ～ 65?mT and a total MFE value about 102.8% at 200?mT whereas the MFE dependence of the MEH-PPV nanoparticles showed significant broadening, with their HWHM ～ 280?mT and a total MFE value of 99% at 550?mT. By a simple theoretical model based on rate equations, the mechanism of the negative magnetic field effect was explained. The observed negative effect was the result of the dominant singlet exciton formation rate in the MEH-PPV nanoparticles. For explaining this negative effect the enhanced triplet-triplet annihilation due to confinement of triplet excitons in the nanoparticles and singlet molecular oxygen-triplet exciton annihilation were proposed.     

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.     

不同极性溶液中MEH-PPV链内激子扩散的研究

本文采用飞秒时间分辨瞬态光栅技术研究了MEH-PPV在不同极性溶液中的内激子扩散行为. 采用宽带连续白光同时探测瞬态吸收和瞬态光栅信息. 系统地研究了MEH-PPV的振动失相行为以及单激子弛豫和粒子数弛豫动力学. 结果表明,在极性较大的溶剂中,样品溶液的弛豫扩散过程会加快.     

Sonochemical synthesis and characterization of new one-dimensional manganese(II) coordination polymer nanostructures

A new Mn(II) coordination polymer, [Mn (L₁)₂(NCS)₂]_n (1) [L₁ = 3,4-bis(4-pyridyl)-5-(2-pyridyl)-1,2,4-triazole] was synthesized by the reaction of ligand L₁ and mixtures of manganese(II) acetate and potassium thiocyanate using the heat gradient method. Compound 1 has been characterized by IR spectroscopy, elemental analyses and X-ray crystallography. The crystal structure of compound 1 was determined by single-crystal X-ray diffraction and shows a new interesting one-dimensional coordination polymer. Nanostructures of compound 1 have been synthesized by sonochemical method. The products were characterized by X-ray powder diffraction, scanning electron microscopy (SEM), and IR spectroscopy. The thermal stability of nano particles of compound 1 was studied by thermal gravimetric and differential thermal analyses.     

钙钛矿/硅叠层太阳电池中平面a-Si:H/c-Si异质结底电池的钝化优化及性能提高

最近,旋涂法制备的钙钛矿/平面硅异质结高效叠层太阳电池引起人们广泛关注,主要原因是相比于绒面硅衬底制备的钙钛矿/硅叠层太阳电池,其制备工艺简单、制备成本低且效率高.对于平面a-Si:H/c-Si异质结电池, a-Si:H/c-Si界面的良好钝化是获得高转换效率的关键,进而决定了钙钛矿/硅异质结叠层太阳电池的性能.本文主要从硅片表面处理、a-Si:H钝化层和P型发射极等方面展开研究,通过对硅片表面的氢氟酸(HF)浸泡时间和氢等离子体预处理气体流量、a-Si:H钝化层沉积参数、钝化层与P型发射极(I/P)界面富氢等离子体处理的综合调控,获得了相应的优化工艺参数.对比研究了p-a-Si:H和p-nc-Si:H两种缓冲层材料对I/P界面的影响,其中高电导、宽带隙的p-nc-Si:H缓冲层既能够降低I/P界面的缺陷态,又可以增强P型发射层的暗电导率,提高了前表面场效应钝化效果.通过上述优化,制备出最佳的P-type emitter layer/aSi:H(i)/c-Si/a-Si:H(i)/N-type layer (inip)结构样品的少子寿命与implied-Voc分别达到2855μs和709 mV,表现出良好的钝化效果.应用于平面a-Si:H/c-Si异质结太阳电池,转换效率达到18.76%,其中开路电压达到681.5 mV,相对于未优化的电池提升了34.3 mV.将上述平面a-Si:H/c-Si异质结太阳电池作为底电池,对应的钙钛矿/硅异质结叠层太阳电池的开路电压达到1780 mV,转换效率达到21.24%,证明了上述工艺优化能够有效地改善叠层太阳电池中的硅异质结底电池的钝化及电池性能.     

Conformational analysis of 2,3-dihydro-3-O-(1,4-naphthoquinon-2-yl)-2-oxo-1,4-naphthoquinone derivatives by the density functional method and IR spectroscopy

We have used the PBE/3z, B3LYP/6-31G, B3LYP/6-31G(d), and B3LYP/6-311G(d) methods to study the conformational mobility of 2,3-dihydro-3-O-(1,4-naphthoquinon-2-yl)-2-oxo-1,4-naphthoquinones (1–4). We have shown that more than 99% of these compounds exist as the major tautomeric form, while differences in the structure of the Q_2H (2,3-dihydro-2-oxo-1,4-naphthoquinones) and Q_1,4 (1,4-naphthoquinon-2-yl) moieties lead to qualitative differences in the internal rotation potentials of the ethyl substituents V(θ_Et−1) and V(θ_Et−2), and consequently each of compounds 1−4 exists as six different rotameric forms. For diquinone 3, we have calculated the dependences of the frequencies (ν) and intensities (A) of the normal vibrations on the torsional angles θ_Et−1 and θ_Et−2, and also on the changes in the geometry of the ether bond. We have found that the values of ν and A for the bands in the carbonyl region of the IR spectrum change little on going from one rotameric form to another, and also for the in-plane bends of the ether bond, and change considerably for the out-of-plane bends of the ether bond. However, for T ≤ 300 K, there is no qualitative change in the overall contour, and it can be interpreted based on a simple additive model. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 5, pp. 573–581, September–October, 2006.     

Effects of molecular weight and polydispersity of poly (3-hexylthiophene) in bulk heterojunction polymer solar cells

This paper reports the effect of the molecular weight (MW) and polydispersity (PD) of poly (3-hexylthiophene) (P3HT) in bulk heterojunction polymer solar cells (BHJ-SCs). The P3HT with low MW and broad PD exhibited higher crystallinity compared to that with high MW and narrow PD. Due to the improved crystallinity, the BHJ-SCs based on P3HT with low MW and broad PD showed performance with a power conversion efficiency of 3.8% with short-circuit currents of −9.90 mA/cm².     

The ArNe-N2O van der Waals trimer: a high resolution spectroscopic study of its rotational spectrum,structure and dynamics

A new ternary van der Waals complex of the type rare gas-rare gas'-linear molecule, ArNe-N₂O, was investigated using a pulsed molecular beam cavity Fourier transform microwave spectrometer. The rotational spectra of six isotopomers of the trimer were studied in detail. These include Ar²⁰Ne-¹⁴N¹⁴NO, Ar²²Ne-¹⁴N¹⁴NO, Ar²⁰Ne-15N¹⁴NO, Ar²²Ne-¹⁵N¹⁴N0, Ar²⁰Ne-¹⁴N¹⁵NO and Ar²²Ne-¹⁴N¹⁵NO. Nuclear quadrupole hyperfine structures of the rotational transitions that are due to the one or two ¹⁴N nuclei were resolved and analysed. The resulting spectroscopic constants were used to provide structural and dynamical information about the trimer. Based on the quartic centrifugal distortion constants, a harmonic force field analysis was performed to estimate the frequencies of the van der Waals vibrational modes. A perturbation of the electronic charge distribution at the site of the central ¹⁴N nucleus of N²0 upon complex formation was detected and discussed. Differences of structural parameters of the trimer as compared to those of the respective dimer units are indicative of the presence of significant three-body non-additive contributions to the interaction energy.     

BF~X(X=-1,0,+1)分子离子基态的结构与势能函数研究

本文利用CCSD 方法,分别选用6-311++g(3df,3pd)、6-311++g(2df,2pd)和6-311++g(df,pd)基组对BF分子和BF~+、BF~-离子基态进行了几何优化和频率计算,并进行了单点能扫描计算.用最小二乘法拟合得到了BF~X(X=-1,0,+1)分子离子基态的Murrell-Sorbie势能函数.与实验及理论结果比较表明,本文对BF分子和BF~+离子基态光谱常数(B_e,α_e,ω_e,ω_ex_e)的计算结果达到了很高的精度.文章还首次给出BF~-离子基态的光谱常数(B_e,α_e,ω_e,ω_ex_e)和力常数(f_2,f_3,f_4),这将为BF~-离子基态的后期研究提供重要参考.研究表明:BF~X(X=-1,0,+1)分子离子基态的势能曲线均具有对应于稳定平衡结构的极小点,说明BF~X(X=-1,0,+1)分子离子基态是稳定存在的.     

BFX(X=-1,0,+1)分子离子基态的结构与势能函数研究

本文基于Gaussian03计算软件利用CCSD方法分别选用6-311++g(3df,3pd)、6-311++g(2df,2pd)、6-311++g(df,pd)基组对BF分子和BF+、BF-分子离子基态进行了几何优化和频率计算,并进行了单点能扫描计算。采用最小二乘法拟合得到了BFX(X=-1,0,+1)分子离子基态的Murell-Sorbie势能函数。与实验及理论结果比较表明,本文对BF分子和BF+分子离子基态的光谱参数和力常数(f2,f3,f4,)的计算结果达到了更高的精度。文章还首次给出BF-分子离子基态光谱参数(和力常数(f2,f3,f4,)理论数据,为BF-分子离子基态的后期研究提供重要的参考。研究表明：BFX(X=-1,0,+1)分子离子基态的势能曲线均具有对应于稳定平衡结构的极小点,说明BFX(X=-1,0,+1)分子离子基态是稳定存在的。