退火处理ZnPc(OC_8H_(17)OPyCH_3I)_8阴极缓冲层的倒置有机太阳能电池

制备了以Zn Pc(OC8H17OPy CH3I)8为阴极缓冲层、P3HT∶PCBM为有源层的有机太阳能电池。对阴极缓冲层Zn Pc(OC8H17OPy CH3I)8薄膜分别进行了溶剂蒸汽退火和过渡舱惰性气体流退火处理,并利用原子力显微镜(AFM)对缓冲层表面形貌进行了表征。结果表明:这两种退火方法都使缓冲层形貌得以改善。电池效率从2.14%提高到3.76%,电流密度从8.12 m A/cm2提高到10.71 m A/cm2,填充因子从0.45提高到0.61。与传统器件相比,退火处理的阴极缓冲层器件的稳定性也得到了改善,器件寿命延长了1.4倍。这种简单阴极界面处理方法为改善聚合物太阳能电池性能提供了有效途径。     

利用Ag_2O/PEDOT:PSS复合缓冲层提高P3HT:PCBM聚合物太阳能电池器件性能的研究

利用Ag2O/PEDOT:PSS(聚(3,4-乙撑二氧噻吩):聚苯乙烯磺酸盐)作为复合阳极缓冲层,制备了P3HT:PCBM(聚(3-已基噻吩):富勒烯衍生物)聚合物太阳能电池器件,并通过改变氧化银插入层的厚度来分析复合缓冲层对器件性能的影响.实验发现,具有阳极缓冲层修饰的器件在退火处理后,光伏性能得到了改善.相比于单一PEDOT:PSS缓冲层的器件,Ag2O/PEDOT:PSS复合缓冲层可以增大器件的短路电流密度和外量子效率,使器件效率得到提高.分析表明,退火处理可以有效改善活性层的薄膜形貌,增加光的吸收和激子的解离,而较薄氧化银的引入,可以有效降低阳极处空穴的输运势垒,提高器件空穴收集效率,并能充当化学间隔层,提高器件光伏性能和稳定性.     

溶剂预处理结合热退火提升聚噻吩结晶度及其光伏性能

活性层的微观形貌在很大程度上决定了聚合物光伏器件的性能表现并依赖于制备工艺条件。为了改善薄膜内部分子排布结构并追求较高的器件光电转化效率,采用溶液法制备了基于P3HT∶PCBM的聚合物太阳能电池(器件结构:ITO/PEDOT∶PSS/P3HT∶PCBM/Al),通过改变器件制备流程中活性层退火处理工艺,研究了热退火、溶剂退火以及溶剂预处理结合热处理的双重退火对聚合物太阳电池性能的影响。研究发现:双重退火的光伏器件的各项性能参数均优于单一退火处理器件,获得了3.25%的光电转化效率。原子力显微镜及X射线衍射仪的表征结果进一步证明:双重退火处理能够在促进聚合物给体良好有序结晶的同时保证共混组分适度地相分离,从而有利于光生激子的解离以及载流子的传输。     

阴极缓冲层对于不同惰性气氛气压退火处理的 P3HT∶PCBM光伏性能的影响

制备了基于聚(3-己基噻吩)(P3HT)与可溶性富勒烯衍生物(PCBM)共混体系的太阳能电池。通过改变活性层退火处理时惰性气氛环境的压强,在一定程度上实现对共混物相分离以及聚合物结晶度的控制,研究了LiF作为阴极缓冲层对不同压强下退火处理的器件性能的影响。实验发现,LiF层的关键作用在于稳定开路电压以及提升短路电流,从而带动转化效率整体提升。结果表明,LiF层可以改善器件活性层与金属电极接触的界面形态,而器件的最终性能则由活性层的微观形貌与电极界面形态共同决定。     

溶剂预处理结合热退火提升聚噻吩结晶度及其光伏性能

活性层的微观形貌在很大程度上决定了聚合物光伏器件的性能表现并依赖于制备工艺条件。为了改善薄膜内部分子排布结构并追求较高的器件光电转化效率,采用溶液法制备了基于P3HT：PCBM的聚合物太阳能电池（器件结构:ITO/PEDOT：PSS/P3HT：PCBM/Al）,通过改变器件制备流程中活性层退火处理工艺,研究了热退火、溶剂退火以及溶剂预处理结合热处理的双重退火对聚合物太阳电池性能的影响。研究发现:双重退火的光伏器件的各项性能参数均优于单一退火处理器件,获得了3.25%的光电转化效率。原子力显微镜及X射线衍射仪的表征结果进一步证明:双重退火处理能够在促进聚合物给体良好有序结晶的同时保证共混组分适度地相分离,从而有利于光生激子的解离以及载流子的传输。     

磁场对P3HT:PCBM活性层的薄膜形貌及光电性能的影响北大核心CSCD

以P3HT(Poly(3-Hexylthiophene))为电子给体,PCBM([6,6]-Phenyl C61Butyric Acid Methyl Ester)为电子受体,在活性层P3HT:PCBM的退火过程中,利用磁场对活性层有机分子的排列取向作用,制备了有机体异质结太阳能电池。研究结果表明:当磁场强度为0.9MA/m时,器件的短路电流密度从7.414A/cm2提高到8.332A/cm2,填充因子也相应地增加,但开路电压却有所降低,最高的光电转换效率为2.562%。由光致发光光谱和原子力显微图像可知,磁场对活性层的结晶度、内部分子排列和表面形貌都有明显的影响。     

磁场对P3HT:PCBM活性层的薄膜形貌及光电性能的影响

以P3HT(Poly(3-Hexylthiophene))为电子给体,PCBM([6,6]-Phenyl C61Butyric Acid Methyl Ester)为电子受体,在活性层P3HT:PCBM的退火过程中,利用磁场对活性层有机分子的排列取向作用,制备了有机体异质结太阳能电池。研究结果表明:当磁场强度为0.9MA/m时,器件的短路电流密度从7.414A/cm2提高到8.332A/cm2,填充因子也相应地增加,但开路电压却有所降低,最高的光电转换效率为2.562%。由光致发光光谱和原子力显微图像可知,磁场对活性层的结晶度、内部分子排列和表面形貌都有明显的影响。     

Au层退火温度对ZnO/Au/ZnO多层膜的结构、光学及电学性质的影响

采用金属有机化学气相沉积(MOCVD)技术在蓝宝石衬底上制备出晶体质量较好的透明导电的ZnO/Au/ZnO(ZAZ)多层膜,其中,Au夹层是通过射频磁控溅射的方法获得。通过对Au夹层进行不同温度的退火处理,研究了Au层退火温度对ZAZ多层膜的结构特性、电学性能和光学特性的影响。利用原子力显微镜(AFM)、扫描电子显微镜(SEM)、X射线衍射(XRD)仪、霍尔效应测试和透射谱分析等测试手段对ZAZ多层膜的性质进行了分析。测试结果表明,在200 ℃下对Au夹层进行快速退火处理,多层膜的结构、电学和光学性质达到最优,表面等离子体效应也更明显。其中,XRD(002)衍射峰的半高宽为0.14°,电阻率为2.7×10^-3 Ω·cm,载流子浓度为1.07×10²⁰ cm^-3,可见光区平均透过率为75.3%。     

基于Al_2O_3/MoO_3复合阳极缓冲层的倒置聚合物太阳能电池的研究

采用旋涂Al_2O_3前驱体溶液和低温退火的方法在活性层上形成Al_2O_3薄膜,并与MoO_3结合形成Al_2O_3/MoO_3复合阳极缓冲层,制备了以聚3-己基噻吩:[6.6]-苯基-C_(61)-丁酸甲酯(P3HT:PC_(61)BM)为活性层的倒置聚合物太阳能电池,并通过改变Al_2O_3前驱体溶液的浓度来分析复合阳极缓冲层对器件性能的影响.结果发现,Al_2O_3/MoO_3复合阳极缓冲层能有效调控倒置聚合物太阳能电池的光电性能及其稳定性.当Al_2O_3前驱体溶液的浓度为0.15%时,器件光伏性能达到最优值,与MoO_3单缓冲层的器件相比,光电转换效率(PCE)由3.85%提高到4.64%;经过80天老化测试后,具有复合阳极缓冲层的器件PCE保留为初始值的76%,而单缓冲层的器件PCE已经下降到50%以下.器件性能得到改善的原因是Al_2O_3/MoO_3复合阳极缓冲层增强了倒置太阳能电池器件阳极对空穴的收集能力,同时钝化了器件活性层,从而提升了太阳能电池器件的光伏性能及其稳定性.     

不同气氛下LaMnO_3缓冲层后退火效应研究北大核心CSCD

在第二代高温涂层导体离子束辅助沉积技术(IBAD)路线中,LaMnO_3(LMO)作为超导层的生长面,直接影响到YBCO的性能,为改善LMO的织构、形貌等,对磁控溅射法制备的LMO薄膜进行了后退火处理,本实验系统研究了后退火处理对LMO物相、织构、表面形貌等的影响,并进一步研究了后退火效应对超导层的影响.结果表明后退火处理有助于改善LMO表面形貌,优化LMO微结构,在潮湿Ar-5%H2气氛下,LMO缓冲层改善率最高,在经湿Ar-5%H2后退火处理的LMO缓冲层上制备的超导层具有最佳的性能,在77K自场下,临界电流密度达到1.2 MA/cm^2.     

Hybrid solar cells using nanorod zinc oxide electrodes and perylene monoimide–monoanhydride dyes

Hybrid solar cells have been fabricated using perylene monoimide–monoanhydride dyes with nanorod zinc oxide electrodes as electron transporting layers. We have investigated the influence of the spacer alkyl chain length of perylene monoimide–monoanhydride (PMIMA) dyes on the device performance in hybrid solar cells using nanorod zinc oxide electrodes. Nanorod zinc oxide electrodes with 50–150 nm of diameter were synthesized in the presence of PEG400 by using microwave heating method. We observed that the dyes with longer and brunched alkyl chains exhibit higher efficiencies in hybrid solar cells. We report the highest efficiency obtained with zinc oxide nanorods under standard conditions for perylene monoimide–monoanhydride derivative with PMIMA_1 that performs 400 mV open circuit voltage, 2.81 mA/cm² short-circuit current and 0.59% overall conversion efficiency.     

Features of Short-Period Oscillations of Microwave Emission from the Solar Active Region before the Flare

The radiation of microwave sources above sunspots at a frequency of 17 GHz gives information about the parameters of solar plasma in the regions where the magneti-field strength is B ~ 2000 G in the transition region between the chromosphere and corona. Short-period oscillations (with a period of several minutes) of microwave emission from solar active regions (ARs) reflect wave processes in magnetic flux tubes of sunspots. Short-period oscillations of microwave emission from AR NOAA 12242 before two flares on December 17, 2014 are analyzed. This analysis is based on solar radio images obtained by means of the Nobeyama Radio Heliograph with a 10″?15″ two-dimensional spatial resolution. The radio maps of the whole solar disk were synthesized in a nonstandard mode with a cadence of 10 s and an averaging time of 10 s. An increase in the power of about ten-minute oscillations of microwave radiation approximately 40 to 50 min before the M1.5 flare (01: 00 UT) is found. On the same day, an increase in the power of ten-minute oscillations is observed about 60 min before the M8.7 flare (04: 42 UT). This effect is similar to the effect found earlier by two groups of authors independently for three-minute oscillations—namely, they observed a sharp increase in three-minute oscillations 15 to 20 min before the radio burst accompanying the flare. The effect in question may be interpreted as an relationship ofMHD waves propagating along the magnetic flux tube of a sunspot and the onset of the solar flare.     

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%.     

混合溶剂对P3HT:PCBM基太阳能电池的影响

以poly(3-hexylthiophene)(P3HT)为电子给体材料,[6,6]-phenyl-C60-butyric acid methyl ester (PCBM)为电子受体材料,制备了纯氯苯(CB)溶剂、纯氯仿(CF)溶剂和氯苯/氯仿(CB/CF)不同比例混合溶剂的共混体系太阳能电池.研究了不同溶剂及不同比例混合的混合溶剂对电池性能的影响.结果表明:以CB/CF(3/1)为溶剂制备的器件,紫外可见吸收光谱和器件外量子效率曲线显示出红移现象,原子力显微图表明P3HT和PCBM间形成良好的相分离结构.在100 mW/cm2强度光照射下,其开路电压Voc为0.61 V短路电流密度Jsc为9mA/cm2,填充因子FF为57.9％,能量转换效率PCE为3.2％.     

高效无空穴传输层碳基钙钛矿太阳能电池的制备与性能研究

碳基钙钛矿太阳能电池因稳定性高、成本低廉而备受关注,但由于钙钛矿与碳电极之间能级匹配度不高,界面阻力大而导致效率不及金属基钙钛矿太阳能电池.本文制备了碳基无空穴传输层FTO/c-TiO₂/m-TiO₂/CH₃NH₃PbI₃/Carbon电池结构.通过对介孔二氧化钛层、钙钛矿层厚度进行优化,并对钙钛矿的薄膜形貌及钙钛矿激发电子寿命、可见光吸收度、载流子的提取与分离等进行深度分析,讨论了电池效率提升的内在机理.当介孔氧化钛层和钙钛矿层达到最优厚度时,钙钛矿太阳能电池获得了开路电压（V_oc）为0.93 V、电流密度（J_sc）为21.75 mA/cm²、填充因子为55%、光电转化效率达到11.11%.同时对电池进行了稳定性研究,在室温湿度为40%–50%的条件下放置15 d电池性能依旧稳定保持原来的95%,优于金属基钙钛矿太阳能电池,从而为碳电极钙钛矿太阳能电池的商业化发展提供了可能.     

Analysis of each branch current of serial solar cells by using an equivalent circuit model

In this paper,based on the equivalent single diode circuit model of the solar cell,an equivalent circuit diagram for two serial solar cells is drawn.Its equations of current and voltage are derived from Kirchhoff’s current and voltage law.First,parameters are obtained from the I–V(current–voltage)curves for typical monocrystalline silicon solar cells(125 mm×125 mm).Then,by regarding photo-generated current,shunt resistance,serial resistance of the first solar cell,and resistance load as the variables.The properties of shunt currents(Ish1and Ish2),diode currents(ID1and ID2),and load current(IL)for the whole two serial solar cells are numerically analyzed in these four cases for the first time,and the corresponding physical explanations are made.We find that these parameters have different influences on the internal currents of solar cells.Our results will provide a reference for developing higher efficiency solar cell module and contribute to the better understanding of the reason of efficiency loss of solar cell module.     

基于聚多巴胺/氧化锌复合阴极缓冲层的倒置聚合物太阳能电池的研究

利用多巴胺氧化自聚合形成聚多巴胺(PDA)与ZnO结合形成PDA/ZnO复合阴极缓冲层,制备了以P3HT:PC_(61)BM为活性层的倒置结构聚合物太阳能电池,通过改变PDA的自聚合时间来分析复合阴极缓冲层对器件性能的影响.实验发现,随着PDA的自聚合时间的增加,聚合物太阳能电池的光电转换效率先增大后减小,当自聚合时间为10 min时,相应器件光伏性能达到最优值,其开路电压V_(OC)为0.66 V,短路电流密度J_(SC)为9.70 mA/cm~2,填充因子FF为68.06%,光电转换效率PCE为4.35%.器件性能改善的原因是由于PDA/ZnO复合阴极缓冲层减小了ZnO与ITO之间的接触电阻,同时PDA中存在大量的氨基有利于倒置太阳能电池阴极对电子的收集.     

Antimony Selenide Thin Film Solar Cells with an Electron Transport Layer of Alq_3

We fabricated Sb_2 Se_3 thin film solar cells using tris(8-hydroxy-quinolinato) aluminum(Alq_3) as an electron transport layer by vacuum thermal evaporation.Another small organic molecule of N,N'-bis(naphthalen-1-yl)-N,N'-bis(phenyl)benzidine(NPB) was used as a hole transport layer.We took ITO/NPB/Sb_2Se_3/Alq_3/Al as the device architecture.An open circuit voltage(V_(oc)) of 0.37 V,a short circuit current density(J_(sc)) of 21.2 mA/cm~2,and a power conversion efficiency(PCE) of 3.79% were obtained on an optimized device.A maximum external quantum efficiency of 73% was achieved at 600 nm.The J_(sc),V_(oc),and PCE were dramatically enhanced after introducing an electron transport layer of Alq_3.The results suggest that the interface state density at Sb_2 Se_3/Al interface is decreased by inserting an Alq_3 layer,and the charge recombination loss in the device is suppressed.This work provides a new electron transport material for Sb_2Se_3 thin film solar cells.     

A new proposal for Si tandem solar cell: Significant efficiency enhancement in 3C–SiC/Si

In order to considerable enhancement of the efficiency of silicon solar cells, in this paper, for the first time, we present a new proposal for silicon based tandem solar cells. For investigation of this idea, we have evaluated the characteristics of 3C–SiC/Si crystalline tandem solar cells connected series by a tunneling junction, under air mass 1.5 global irradiance spectrums. A 2D simulation including the effects of surface passivation, back surface field (BSF), and carrier tunneling have been performed to obtain the optical and electrical characteristics of single junction silicon, 3C–SiC, and finally the tandem cells. The obtained data illustrate that the best design parameters considering the experimental limitations can be obtained. High energy conversion efficiency for the proposed structure of 26.09% has been achieved for 3C–SiC/Si tandem structure driven by 20.49% and 17.86% conversion efficiencies of single junction Si and 3C–SiC solar cells, respectively. Our results justifies that the higher conversion efficiency of the Si-based tandem structure compared with 3C–SiC and Si cells stems from enhancement of open circuit voltage and fill factor parameter at the hands of decrease in short circuit current limited by the top 3C–SiC cell.     

一种高效稳定的光伏LED照明系统设计

为提高光伏照明系统中太阳能电池的光能利用率,对太阳能电池输出进行最大功率跟踪。设计以最大功率跟踪芯片SM72442为核心的太阳能充电控制电路,采用光伏全桥驱动芯片SM72295驱动MOS管,构成同步Buck电路,实现太阳能输出最大功率跟踪;利用LED驱动芯片XL6005设计LED驱动电路。测试数据表明,太阳能光伏电池的充电效率平均达到87.92%,LED驱动电路效率最高为91.6%。系统工作稳定,能满足特定场合下的照明需求。