一种新颖的制备聚合物光电薄膜的旋涂装置

设计了一种新颖的制备聚合物光电薄膜的旋涂装置.该设计在传统旋涂装置的基础了,通过增加聚合物溶液载台转盘法向进动功能,改进了聚合物溶液成膜质地疏松、致密度不高问题,减少了成膜过程中产业气泡等缺陷的几率.通过增加聚合物溶液载台转盘径向变轴功能,改善了聚合物薄膜径向厚度的均匀性,从而可以借助于旋涂法制备更大尺寸的薄膜器件.理论和试验结果表明,该项改进设计对提高聚合物光电薄膜的制备质量有一定的实用价值.     

阴极材料对有机太阳电池性能的影响

分别用Al、LiF/Al和Ca/Al制备了三种不同阴极材料的体相异质结有机太阳电池。对其光电特性进行了表征,分析了不同阴极材料对电池性能的影响机制。结果表明:所制备的有机太阳电池在10–1W/cm2辐照度的光照下,开路电压分别为0.419 3,0.565 0和0.591 1 V,能量转换效率分别为1.17%、2.06%和1.91%;采用LiF/Al层状阴极制备的有机太阳电池具有更高的能量转换效率;功函数愈低的材料做阴极,有机太阳电池的能量转换效率也愈高。     

1,3-二巯基丙烷对聚合物/非富勒烯太阳电池的影响

选用1,3-二巯基丙烷(DMP)作为添加剂加入到聚合物材料PBDB-T与非富勒烯材料ITIC的共混体系中,制备以PBDB-T∶ITIC作为活性层材料的体异质结聚合物太阳电池。实验发现,DMP可以有效地改善活性层的形貌,促进激子的产生与解离。DMP对聚合物的结晶形貌改善的作用较小,但对非富勒烯材料ITIC的结晶结构有序性的影响显著。将DMP加入活性层中,可使非富勒烯材料ITIC晶畴的相干长度显著增加,这意味着ITIC结晶结构有序性的提高,这有利于电子的传输。加入质量分数1%的DMP后,器件的光电转换效率由未添加DMP时的7.80%提高至8.98%,证明DMP的应用是一种提高聚合物/非富勒烯太阳电池性能的简单高效的方法。     

有机层／阴极界面修饰对体异质结聚合物太阳能电池性能的影响

通过制备四种不同结构的器件,详细分析研究了活性层／阴极界面修饰对P3HT:PCBM聚合物体异质结太阳能电池性能的影响。当在P3HT:PCBM薄膜上旋涂一层PCBM,并蒸镀0.5 nm LiF时所制备的器件的填充因子和光电转换效率都得到较大的提高。对器件的光电性能和薄膜的形貌进行深入分析,阐明界面修饰的作用机理。     

影响聚合物电致发光器件旋涂膜厚因素的研究

采用正交试验设计,应用方差分析方法,研究了旋涂工艺中聚合物溶液的浓度、匀胶机的旋涂速度和加速度以及旋涂时间对所制备的薄膜厚度的影响.试验和分析结果表明:溶液浓度和旋涂速度对薄膜厚度具有显著性的影响,而旋涂加速度和旋涂时间对它的影响则不显著.使用旋涂工艺制备聚合物薄膜时,合理选择溶液浓度和旋涂速度,对于优化器件的性能具有非常重要的作用.     

背面刻蚀对单晶硅太阳电池性能影响的研究

为了减少太阳电池载流子的背面复合,采用离子束对沉积完SiNx减反射膜后的单面扩散和双面扩散的单晶硅片背面进行刻蚀,研究了刻蚀时间对太阳电池性能的影响.采用标准的太阳电池单片测试仪测试电池性能.发现背面经离子束刻蚀后,单面扩散和双面扩散电池片的并联电阻、开路电压、填充因子和转换效率都有所提高,而串联电阻和短路电流的变化则...     

掺碳对杂质光伏硅太阳电池性能的影响

杂质光伏太阳电池是一种能够利用那些能量小于禁带宽度的太阳光子以提高电池转换效率的新型太阳电池。利用数值方法研究在硅电池中掺入碳杂质以形成杂质光伏太阳电池,分析掺碳对电池性能的影响。结果表明:利用杂质光伏效应掺入碳杂质能够增加子带光子的吸收,使得电池转换效率提高约2%;转换效率的提高在于电池的红外光谱响应的延展。由此可以得出:利用杂质光伏效应在硅电池中掺碳形成杂质光伏太阳电池是一种能够提高电池转换效率的新途径。     

退火方式及PCBM阴极修饰层对聚合物太阳电池的影响

研究了不同退火方式及PCBM阴极修饰层对聚合物太阳电池性能的影响。与前退火相比,后退火的器件性能显著提高,电池的开路电压Voc由0.36V增加到0.60V,能量转换效率η从0.85%提高到1.93%,短路电流密度Jsc和填充因子FF也有不同程度的改善;在电池的活性层与Al电极间沉积一定厚度的PCBM阴极修饰层也能改善电池的性能,当PCBM厚度为3nm时,聚合物太阳电池在100mW.cm-2强度光照下,Voc为0.59V,Jsc为6.43mA.cm-2,FF为55.1%,η为2.09%。     

不同薄膜对n型IBC太阳电池性能的影响

叉指背接触式(IBC)太阳电池因正面没有金属栅线遮挡,具有较高的光电转换效率。但由于IBC太阳电池在制备过程中需要采用光刻掩模技术进行发射极和背电场隔离,导致工艺流程复杂、电池片稳定性较差,难以实现大规模生产。研究了不同厚度的SiO₂薄膜、SiN_x薄膜和SiO₂-SiN_x叠层薄膜对IBC太阳电池钝化性能、减反射效果、热稳定性能和电性能的影响,实验结果表明,SiO₂-SiN_x叠层薄膜在较宽的光谱范围内减反射效果更佳,高温热生长的20 nm厚的SiO₂薄膜便表现出良好的热稳定性,当选用SiO₂-SiN_x(厚度分别为20和40 nm)叠层薄膜时,制备的IBC太阳电池光电转换效率稳定,可达24.1%,对应的开路电压为698 mV,短路电流密度为43.25 mA/cm²,填充因子为79.87%。     

聚乙二醇阴极修饰层改善聚合物太阳能电池光电性能的研究

通过将聚乙二醇(PEG)掺入活性层制备聚合物太阳 能电池,利用PEG的迁移特性获得阴极修饰层,研 究PEG阴极修饰层对聚合物太阳能电池光电性能的影响。X射线光电子能谱(XPS)分 析表明,掺入活性层中的 PEG迁移到活性层与Al电极之间,形成了阴极缓冲层。吸收光谱、电流密度-电压 特性曲线和外量子 效率谱的分析表明,PEG阴极缓冲层的形成改善了活性层与阴极的界面接触特性, 降低了活性层与电 极之间的能级势垒,有利于载流子传输,因此显著地改善了聚合物太阳能电池的光电性能, 使得器件的开 路电压Voc、短路电流密度Jsc和填充因子(FF)都有明显提高。当P3HT:PCBM 活性层中掺入体积比为0.5%的PEG时,聚合物太阳能电池的能量转换 效率(P CE)最高,达到了3.07%,比未掺杂PEG的参考器件提 高了38.5%。     

超薄PCBM层提高有机太阳电池效率

为研究超薄PCBM层对有机太阳电池的影响,制备了含和不含超薄PCBM层的两种不同结构的体相异质结太阳电池,电池结构分别为:ITO/PEDOT:PSS/P3HT+PCBM/PCBM/AI,ITO/PEDOT:PSS/P3HT+PCBM/Al.测试结果表明:所制备电池的开路电压分别为0.599 2V和0.572 7 V,能量转换效率分别为2.24％、1.21％,超薄PCBM层起到了电子传输的作用.     

Improvement in polymer solar cell performance and eliminating light soaking effect via UV-light treatment on conjugated polyelectrolyte interlayer

A new conjugated polyelectrolyte material, namely, poly [9,9-bis((6′-N,N,N-trimethylamino)hexyl)-fluorene-alt-co-benzoxadiazole dibromide] (PFBD) is reported as electron transport layer (ETL) in polymer solar cells. We observed a light-soaking effect and described how a pre-UV light treatment on PFBD ETL is essential for attaining higher efficiencies (>7%) and negate the light-soaking problem. The pre-UV light treatment on PFBD layer is found to directly influence its molecular structure and result in reduction of the work function and increased electron mobility in PFBD which corroborates well with the observed lower series resistances obtained from dark current analysis and impedance spectra, and therefore enhancement in open-circuit voltage and fill factor. Moreover, after the pre-UV light treatment, the maximal efficiency of the solar cells retains at a nearly similar level for at least 26 days.     

Enhanced efficiency in polymer solar cells by incorporation of phenothiazine-based conjugated polymer electrolytes

The power conversion efficiency (PCE) of bulk hetero-junction type polymer solar cells (PSCs) based on poly(3-hexylthiophene) and (6,6)-phenyl-C61-butyric acid methyl ester can be enhanced by insertion of the thin layer of phenothiazine (PT)-based conjugated polymer electrolytes (CPEs), poly{10-[4-(N,N,N-trimethylammonium)butyl]-10H-phenothiazine} bromide (PHPT) and poly{10-butyl-10H-phenothiazine-alt-10-[4-(N,N,N-trimethylammonium)butyl]-10H-phenothiazine} bromide (PcoPT), at the cathode interface. The PHPT has quaternary ammonium salt on every side chains on PT rings whereas PcoPT has quaternary ammonium salt on the side chain on PT rings alternatively. Interestingly, regardless of high HOMO energy levels of PT-based CPEs (ca 5.0 eV), the thin layer of CPE at the cathode interface enhances the PCE by the formation of interface dipole which reduces the work function and a Schottky barrier at the cathode. It is also shown that the number of accumulated ionic groups of PcoPT on the photoactive active is larger than that of PHPT owing to the arrangement of side chain on the CPE backbone. In a similar way, the thin layer of PcoPT exhibits substantially better wetting ability on the photoactive layer than that of PHPT. Thus, the device with PcoPT exhibits higher short circuit current and fill factor than those of PSC with PHPT.     

Formation of charge‐transfer complexes significantly improves the performance of polymer solar cells based on PBDTTT‐C‐T: PC71BM

By adding appropriate proportions of nitrobenzene (C₆H₅NO₂) to the blended solution of poly{[4,8‐bis‐(2‐ethyl‐hexyl‐thiophene‐5‐yl)‐benzo[1,2‐b:4,5‐b′]dithiophene‐2,6‐diyl]‐alt‐[2‐(2′‐ethyl‐hexanoyl)‐thieno[3,4‐b]thiophen‐4,6‐diyl]}:[6,6]‐phenyl‐C71‐butyric acid methyl ester (PBDTTT‐C‐T: PC₇₁BM), we substantially improved the power conversion efficiency from the best reported value of 7.48–8.88%. Experiments and simulations show that nitrobenzene and PBDTTT‐C‐T form stable coplanar charge‐transfer complexes through hydrogen bonds. Formation of the PBDTTT‐C‐T‐C₆H₅NO₂ complex simultaneously increases the external quantum efficiency. The underlying mechanisms of increased external quantum efficiency are attributed to the following: (i) higher lowest unoccupied molecular orbital (LUMO) of PBDTTT‐C‐T‐C₆H₅NO₂ for more efficient photoinduced electron transfer to the LUMO of PC₇₁BM and (ii) efficient quenching of fluorescence in the active layers due to formation of the PBDTTT‐C‐T‐C₆H₅NO₂ complex. This discovery clearly illustrates the potential of hydrogen‐bonded complexes as a new route for efficient polymer‐based photovoltaic devices. Copyright © 2014 John Wiley & Sons, Ltd.     

ZnO纳米颗粒表面缺陷对有机太阳能电池性能的影响

用温度控制ZnO纳米 颗粒粒径的大小,研究了颗粒粒径对表面缺陷的影响。由透射电镜(TEM)、紫外-吸收光谱 和荧光光谱测试表明,随着反应温度升高,ZnO纳米颗粒的尺寸增加,比表面积显著下降, 表面缺陷的体密度降低。将不同反应温 度下的ZnO纳米颗粒应用于ITO/ZnO/P3HT:PCBM/MoO₃/Ag结构的有机太阳能电池中,进一 步研究了缺陷对电池性能的影 响。实验结果表明,60℃下ZnO纳米颗粒薄膜作为电子传输层的器件 效果最好,电池效率可以达到3.05%。 这表明在一定范围内,ZnO纳米颗粒越大,缺陷密度越低,越有利于器件中电子的传输从而 提高太阳能电池器件的短路电流密度和光电转化效率。     

Effects of defect states on the performance of CuInGaSe2 solar cells

Device modeling has been carried out to investigate the effects of defect states on the performance of ideal CulnGaSe2 （CIGS） thin film solar cells theoretically. The varieties of defect states （location in the band gap and densities） in absorption layer CIGS and in buffer layer CdS were examined. The performance parameters： open-circuit voltage, short-circuit current, fill factor, and photoelectric conversion efficiency for different defect states were quantitatively analyzed. We found that defect states always harm the performance of CIGS solar cells, but when defect state density is less than 10 14 cm-3 in CIGS or less than 10 18 cm-3 in CdS, defect states have little effect on the performances. When defect states are located in the middle of the band gap, they are more harmful. The effects of temperature and thickness are also considered. We found that CIGS solar cells have optimal performance at about 170 K and 2 μm of CIGS is enough for solar light absorption.     

SILAR次数对In掺杂CdS量子点敏化太阳电池的影响

以In掺杂CdS量子点太阳能电池为例,讨论了SILAR次数对In掺杂CdS量子点敏化太阳能电池性能的影响。通过SEM、EDS、IPCE、紫外吸收光谱、J-V曲线、EIS等实验测试结果表明,当In掺杂CdS的摩尔比固定在1:5时,随着SILAR次数的增加,电池的短路电流密度、开路电压和光电转换效率都随着增加,当SILAR次数为6次时,In掺杂CdS的QDSCs光电转化效率达到了最大值(η=0.76%)。随着SILAR次数的继续增加,其光电转换效率将会下降。     

Inverted polymer solar cells integrated with small molecular electron collection layer

An efficient inverted polymer solar cell (PSC) is reported by integrating a small molecular electron collection layer (ECL) between indium tin oxide (ITO) cathode and the photoactive layer of blended poly(3-hexylthiophene) and [6,6]-phenyl C61 butyric acid methyl ester (P3HT:PCBM). The ECL is composed of a cesium carbonate-doped tris(8-hydroxyquinolinato) aluminum (Cs₂CO₃:Alq₃) layer. As determined by photoelectron spectroscopy and electrical measurements, the Cs₂CO₃ doping induces suitable energy level alignment at the ITO/Cs₂CO₃:Alq₃/PCBM interface and the increase in bulk conductivity of organic ECL, which are favorable to electron extraction through Cs₂CO₃:Alq₃ to ITO cathode. In addition, optical simulation indicates that the Cs₂CO₃:Alq₃ layer can act as an optical spacer to modulate the region of highest incident light intensity within the photoactive layer, where absorption and charge dissociation are efficient. The inverted PSC with an optimized Cs₂CO₃:Alq₃ ECL exhibits a power conversion efficiency of 4.83%. The method reported here provides a facile approach to achieve high-performance inverted PSCs at low processing temperature.