Application of AlGaInP with Sb Incorporation in Lattice-Matched 5-Junction Tandem Solar Cells

It is well known that conventional GaInP/GaInAs/Ge three-junction(3J) solar cells are difficult to continue to ascend when the efficiencies reach 32% and 42% under AMO and AM1.5 D concentrated, respectively. In AlGaInP/AlGaInAs/GaInAs/GaInNAs/Ge five-junction(5J) solar cells, the performance of the AlGaInP, AlGaInAs and GaInNAs sub cell is the key factor for conversion efficiency of the 5J solar cell. We investigate the AlGaInP/AlGaInAs/Ge 3J solar cell. By incorporating surfactant trimthylantimony into the AlGaInP material,the crystal quality of AlGalnP is improved and the spectrum absorption range of AlGaInAs is extended. The current density of each sub cell exceeds 11.3 mA/cm~2 as is desired. Then we apply this 3J structure to grow the lattice-matched 5J solar cell and obtain the short circuit current of 134.96 mA, open circuit voltage of 4399.6 mV,fill factor of 81.7% and conversion efficiency of 29.87%.     

Electrical Property of Infrared-Sensitive InAs Solar Cells

InAs infrared-sensitive solar cells are fabricated by using the films grown by the liquid phase epitaxy technique. The film microstructures are characterized by x-ray diffraction and scanning electronic microscopy. The current-voltage characteristics of the solar cells in the dark and under AM1.5 illumination at 300 K and 77 K are discussed. The conversion efficiency of p-InAs/n-sub InAs cells decreases when the thickness of the p-type film changes from 1.7 μm to 3.5 μm, which is caused by the reduced effective photons near p？n junction. The p-InAs/n-InAs/n-sub InAs solar cell with the conversion efficiency of 7.43% in 1-2.5 μm under AM1.5 at 77 K is obtained. The short circuit current density increases dramatically with decreasing temperature due to the weakened effect of phonon scattering.     

Effects of 1.0-11.5 MeV Electron Irradiation on GaInP/GaAs/Ge Triple-junction Solar Cells for Space Applications

GalnP/GaAs//Ge triple-junction solar cells are irradiated with 1.0, 1.8, and 11.5 MeV electrons with fluence rang- ing up to 3 × 10^15, 3×10^15, and 3×10^14cn^-2, respectively. Their performance degradation effects are analyzed by using current-voltage characteristics, spectral response measurements, and electron irradiation-induced dis- placements. The degradation rates of the maximum power and the spectral response of the solar cells increase with the electron fluence, and also increase with the increasing electron energy. It is observed that the spectral response of the GaAs middle cell degrades more significantly than that of the GaInP top cell.     

Preparation of ZnO Nanospheres and Their Applications in Dye-Sensitized Solar Cells

ZnO nanospheres are synthesized by a two-step self-assembly method. X-ray diffraction pattern and Raman scattering spectra measurements show that all the samples present a typical wurtzite structure. A regular sphere shape is inspected by field emission scanning electron microscope and transmission electron microscope for the samples. It is shown that the as-synthesized ZnO nanosphere is composed of numbers of primary particles with size of around 1Ohm. A possible growth mechanism for the two-step self-assembly ZnO nanosphere is proposed. After applying the ZnO nanospheres to dye-sensitized solar cells （DSSCs）, a 117% increase of the overall light to electricity conversion efficiency η is observed compared with that of the ZnO nanopartieles based DSSCs. Associated with the UV-vis results, light scattering is assigned to the great improvement of η.     

激光精密刻蚀技术在硅太阳电池制备工艺中的应用

依据光学谐振腔的图解分析与设计方法,对以Nd:YAG固体激光器作光源的激光切割机进行了设计改进,实现了高亮度激光输出.并利用该设备对硅太阳电池进行了激光精密切割试验,使埋栅太阳电池电极槽达到了平均宽度为150±5 μm,槽深100±10 μm的设计指标.在发射结卷包太阳电池所用的硅衬底片上进行激光精密穿孔,目前最小孔径为20 μm.通过应用激光精密刻蚀技术,现将埋栅太阳电池光电转换效率提高到了21%,接近该领域的世界先进水平.     

太阳能电池特性实验中的计算机辅助测量

利用计算机和Labcoder数据采集分析系统,对传统的“太阳能电池伏安特性测量”实验进行改进。利用改进后的实验装置,太阳能电池在光照下随着负载的改变,实现了输出电流和电压的动态实时采集,提高了实验效率。     

Enhanced Efficiency of Metamorphic Triple Junction Solar Cells for Space Applications

Metamorphic In_(0.55)Ga_(0.45)P/In_(0.06)Ga_(0.94)As/Ge triple-junction(3J-MM) solar cells are grown on Ge(100) substrates via metal organic chemical vapor deposition. Epi-structural analyses such as high resolution x-ray diffraction, photoluminence, cathodoluminescence and HRTEM are employed and the results show that the high crystal quality of 3J-MM solar cells is obtained with low threading dislocation density of graded buffer(an average value of 6.8×10~4/cm~2). Benefitting from the optimized bandgap combination, under one sun, AMO spectrum,25℃ conditions, the conversion efficiency is achieved about 32%, 5% higher compared with the lattice-matched In_(0.49)Ga_(0.51)P/In_(0.01)Ga_(0.99)As/Ge triple junction(3J-LM) solar cell. Under 1-MeV electron irradiation test, the degradation of the EQE and Ⅰ-Ⅴ characteristics of 3 J-MM solar cells is at the same level as the 3J-LM solar cell.The end-of-life efficiency is ~27.1%. Therefore, the metamorphic triple-junction solar cell may be a promising candidate for next-generation space multi-junction solar cells.     

银纳米颗粒对聚合物太阳能电池性能的提高

采用水溶性银纳米颗粒附着在反型太阳能电池的电子传输层上,用以提高有机太阳能电池的短路电流。所制备的器件结构为ITO/ZnO/Ag NPs/P3HT(Poly 3-hexylthiophene):PC_[60]BM/MoO₃/Ag。其金属银纳米颗粒的表面等离激元在410 nm处出现了共振吸收峰,半峰全宽约为60 nm。器件的光电流在可见光范围内均有所增加,短路电流相对于标准器件提高了20.2%,光电转化效率相对提高了17.2%。     

The Development of Highly Fluorescent Hemicyanine and Dicyanoisophorone Dyes for Applications in Dye-Sensitized Solar Cells

Journal of Fluorescence - Ruthenium-based metal complex dyes have been employed extensively in dye-sensitized solar cells (DSSCs) as photosensitizers, but the cost and toxicity of metal complexes...     

多晶硅片反应离子刻蚀制绒后扩散工艺的匹配性

研究了多晶硅片在反应离子刻蚀制绒后与扩散工艺的匹配性.在相同的扩散工艺下,反应离子刻蚀制绒后硅片的方块电阻值比酸制绒工艺硅片的方块电阻值高3～11 Ω/□,而且其方块电阻不均匀度值约为普通酸制绒工艺硅片的方块电阻不均匀度值的80％.测试了反应离子刻蚀制绒后多晶硅太阳能电池的外量子效率,其外量子效率在340～1 000 nm波段范围与酸制绒多晶硅太阳能电池相比提高了约10％.对反应离子刻蚀制绒电池的电性能进行了分析,提出了与反应离子刻蚀制绒工艺匹配的高方阻扩散工艺.通过优化调整扩散工艺气体中的小氮和干氧流量,获得了在80 Ω/口方块电阻下,反应离子刻蚀制绒多晶硅电池的光电转换效率提升至17.51％,相对于酸制绒多晶硅电池的光电转换效率提高了0.5％.     

利用吡啶添加剂提高钙钛矿太阳能电池的光伏性能

研究了吡啶作为添加剂对一步法制备甲胺铅碘钙钛矿太阳能电池光电性能的影响.利用SEM、AFM、XRD、UV-Vis、PL等手段研究了不同吡啶掺杂浓度对制备的CH3 NH3 PbI3薄膜的表面形貌、结晶度和光学性能的影响.研究结果表明:少量的吡啶掺杂可以提高钙钛矿薄膜的覆盖率及降低薄膜的表面粗糙度.当在CH3 NH3 PbI3前驱体溶液中添加体积分数为1%的吡啶时,制备的钙钛矿太阳能电池的能量转换效率达到7.33%,而未加吡啶的对比器件效率仅为1.01%.进一步添加吡啶会导致钙钛矿材料的降解.     

Cu掺杂对CdS薄膜结构、光致发光及CdS/CdTe电池性能的影响

采用化学浴沉积(CBD)法在FTO(SnO2∶F)/Glass衬底上制备了Cu掺杂的CdS薄膜.用电感耦合等离子体-原子发射光谱(ICP-AES)测得不同Cu掺杂浓度的薄膜中Cu/Cd原子比分别为0.5％、1.5％、5％.分别用X射线衍射(XRD)、扫描电镜(SEM)、光致发光谱(PL)、紫外-可见-近红外反射透射谱对薄膜样品进行表征.研究了Cu掺杂对CdS薄膜的晶体结构,微观形貌以及体内点缺陷的影响.用Cu掺杂的CdS薄膜作为N型层制备CdTe太阳能电池,研究了CdS层中Cu对电池性能的影响.     

Updated Progresses in Perovskite Solar Cells

In the last decade, perovskite solar cells(PSCs) have greatly drawn researchers' attention, with the power conversion efficiency surging from 3.8% to 25.5%. PSCs possess the merits of low cost, simple fabrication process and high performance, which could be one of the most promising photovoltaic technologies in the future. In this review, we focus on the summary of the updated progresses in single junction PSCs including efficiency, stability and large area module. Then, the important progresses in tandem solar cells are briefly discussed. A prospect into the future of the field is also included.     

Significant Improvement of Passivation Performance by Two-Step Preparation of Amorphous Silicon Passivation Layers in Silicon Heterojunction Solar Cells

The key feature of amorphous/crystalline silicon heterojunction solar cells is extremely low surface recombination,which is related to superior passivation on the crystalline silicon wafer surface using thin hydrogenated amorphous silicon(a-Si:H)layers,leading to a high open-circuit voltage.In this work,a two-step method of a-Si:H passivation is introduced,showing excellent interface passivation quality,and the highest effective minority carrier lifetime exceeds 4500 μs.By applying a buffer layer deposited through pure silane plasma,the risk of film epitaxial growth and plasma damage caused by hydrogen diluted silane plasma is effectively reduced.Based on this,excellent passivation is realized through the following hydrogen diluted silane plasma process with the application of high density hydrogen.In this process,hydrogen diffuses to a-Si/c-Si interface,saturating residual dangling bonds which are not passivated by the buffer layer.Employing this two-step method,a heterojunction solar cell with an area of 239 cm~2 is prepared,yielding to open-circuit voltage up to 735 mV and total-area efficiency up to 22.4%.     

电解质中添加氧化物颗粒对染料敏化太阳电池性能的增强

"在液态电解质中加入纳米TiO2、微米TiO2、Al2O3和ZrO2颗粒后,在一定的氧化物含量下,都不同程度地提高了DSC的光电特性,而以加入12.5%的纳米TiO2 (P25)得到最高的提高,达到5.5%,比没有加入氧化物颗粒的DSC效率提高达到51%以上．利用电化学阻抗谱和循环伏安法研究了在染料敏化太阳电池液态电解质中加入各种氧化物颗粒对电池电解质特性的影响,结果发现,加入氧化物颗粒后,由于界面效应,提供了I3-的快速扩散通道,从而I3-扩散系数得到较大提高,电解质/Pt电极间的电荷传输电阻下降,改善     

基于电致发光影像的太阳能电池瑕疵检测

太阳能电池制造的复杂性决定其在制造过程中会有很多瑕疵产生,瑕疵的存在会大大影响太阳能电池的发电效率和使用寿命。本文运用电致发光影像技术来凸显瑕疵,针对影像中的瑕疵人工检测率低且缺乏客观性的问题,选用了基于统计的瑕疵检测算法。检测时,选取扩展Haar特征作为样本像素点的特征值,应用改进的模糊C均值聚类法对正常样本进行分群训练,通过判断测试样本是否在正常样本群组之中的方法实现了样本的瑕疵检测,并近似地给出了瑕疵位置。实验结果表明,该方法对太阳能芯片电致发光影像中瑕疵的总辨识率可以达到96%。     

利用蛾眼结构提高有机太阳能电池光吸收效率的理论研究

为提高有机太阳能电池(OSCs)的能量转换效率,将蛾眼微结构应用于OSCs上.通过理论模拟计算,得出在有机层厚度一定的情况下,带有蛾眼微结构的OSCs相比于普通平板结构的OSCs的光吸收效率有较大的提高.通过对微结构形貌、周期和高度的优化,使蛾眼结构OSCs的光吸收效率比普通平板OSCs提高了11.3％.器件光场分布的模拟计算表明,光吸收效率的提高是由蛾眼结构减反增透的效果和表面等离子体(SPP)增强吸收共同导致的结果.     

锁相载流子成像技术在太阳能电池中的应用

提出了一种基于锁相载流子成像技术的太阳能电池特性研究方法。激光激励的红外光生载流子辐射测量技术是一种动态的近红外调制的光致发光成像技术,已经被证实为半导体输运参数的一种行之有效的非接触测量方法。提出的锁相载流子成像技术则是一种基于红外相机的动态近红外光生载流子辐射光致发光法,它是光生载流子技术在成像领域的延伸。采用锁相载流子成像系统对10片样片进行了实验,并对获得的红外图像进行了统计分析,由此得到了载流子成像统计参数与太阳能电池光电转换效率间的相关特性。结果表明,锁相载流子成像的统计参数可用于表征太阳能电池的效率。