不同吸收层结构的非晶硅/锗太阳能电池转换效率的模拟计算(英文)

设计了2种太阳能电池结构：结构A为a-Si：H/a-Si0.65Ge0.35：H多吸收层结构;结构B为a-Si0.65Ge0.35：H单吸收层结构。采用AMPS-ID程序分析了2种电池结构的光电性质。模拟计算中光学吸收系数和缺陷浓度均采用实验数据以便确保模拟的可靠性。分析了2种电池结构的短路电流密度、断路电压、填充因子和转换效率。结果表明：对于结构A,当吸收层厚度达180nm时,转换效率达到饱和值6.88%;对于结构B,当吸收层厚度达45nm时,转换效率达到最大值3.44%;利用载流子产生和复合机制分析了采用多吸收层结构更有利于提高太阳能电池的转换效率。     

Optimization of an Electron Transport Layer to Enhance the Power Conversion Efficiency of Flexible Inverted Organic Solar Cells

The photovoltaic (PV) performance of flexible inverted organic solar cells (IOSCs) with an active layer consisting of a blend of poly(3-hexylthiophene) and [6, 6]-phenyl C₆₁-butlyric acid methyl ester was investigated by varying the thicknesses of ZnO seed layers and introducing ZnO nanorods (NRs). A ZnO seed layer or ZnO NRs grown on the seed layer were used as an electron transport layer and pathway to optimize PV performance. ZnO seed layers were deposited using spin coating at 3,000 rpm for 30 s onto indium tin oxide (ITO)-coated polyethersulphone (PES) substrates. The ZnO NRs were grown using an aqueous solution method at a low temperature (90°C). The optimized device with ZnO NRs exhibited a threefold increase in PV performance compared with that of a device consisting of a ZnO seed layer without ZnO NRs. Flexible IOSCs fabricated using ZnO NRs with improved PV performance may pave the way for the development of PV devices with larger interface areas for effective exciton dissociation and continuous carrier transport paths.     

The Influence of Physical Properties of ZnO Films on the Efficiency of Planar ZnO/Perovskite/P3HT Solar Cell

ZnO thin films prepared by pulsed laser deposition at low temperature are utilized as the electron transport layer in CH₃NH₃PbI_3?xCl_x‐based perovskite solar cells with a planar heterojunction structure. Oxygen pressure greatly influences the transparent and conductive properties of ZnO films, which are extremely important as electron transport layer for the perovskite solar cells. The transparent and conductive properties of the films under different oxygen pressures are studied by ultraviolet‐visible spectrophotometer and Hall effect measurement system. Through controlling the oxygen pressure, transparent ZnO films with high conductivity are grown and adopted as electron transport layer for planar perovskite solar cell with a power conversion efficiency of 6.3%. After further surface modification of ZnO electron transport layer with [6,6]‐phenyl‐C61‐butyric acid methyl ester, the efficiency of the planar solar cell increases to 7.5%.     

Au修饰的全纳米颗粒自组装SnO2/TiO2薄膜及其DSSCs阻挡层应用

采用硼氢化钠还原金盐溶液,制备了晶粒尺寸为5 nm的金溶胶,以静电吸附的方法将Au纳米晶均匀地沉积在FTO玻璃基全纳米颗粒组装的SnO2/TiO2薄膜内,用SEM、EDS、TEM、光电流密度等方法对金修饰的全纳米颗粒组装SnO2/TiO2薄膜(Au-SnO2/TiO2)进行了表征.金纳米晶修饰后,光电流密度较相同厚度的SnO2/TiO2薄膜提高了128.3％,更加有利于光生电子的迁移.将Au-SnO2/TiO2薄膜用作染料敏化太阳能电池(Dye-sensitized solarcells,DSSCs)的阻挡层后,发现复合薄膜有效地阻止了导电玻璃基底上光生电子与电解液中I3-的复合,提高了DSSCs的光电转换效率.不同厚度的Au-SnO2/TiO2阻挡层复合薄膜中,含6层Au-SnO2/TiO2复合薄膜阻挡层的DSSCs最终效率为7.12％,较常用的TiCl4稀溶液预处理FTO玻璃的工艺(6.06％)提高了17.5％.     

The Impact of Backbone Fluorination and Side-Chain Position in Thiophene-Benzothiadiazole-Based Hole-Transport Materials on the Performance and Stability of Perovskite Solar Cells

Perovskite solar cells (PSCs) currently reach high efficiencies, while their insufficient stability remains an obstacle to their technological commercialization. The introduction of hole-transport materials (HTMs) into the device structure is a key approach for enhancing the efficiency and stability of devices. However, currently, the influence of the HTM structure or properties on the characteristics and operational stability of PSCs remains insufficiently studied. Herein, we present four novel push-pull small molecules, H1-4, with alternating thiophene and benzothiadiazole or fluorine-loaded benzothiadiazole units, which contain branched and linear alkyl chains in the different positions of terminal thiophenes to evaluate the impact of HTM structure on PSC performance. It is demonstrated that minor changes in the structure of HTMs significantly influence their behavior in thin films. In particular, H3 organizes into highly ordered lamellar structures in thin films, which proves to be crucial in boosting the efficiency and stability of PSCs. The presented results shed light on the crucial role of the HTM structure and the morphology of films in the performance of PSCs.     

高效晶硅太阳电池的发展与抑制光衰的研究进展

晶硅太阳电池在光伏发电中占有80％以上的市场份额,其科技进步主导着光伏发电的走向.随着晶硅太阳电池光电转换效率的提高,其光衰也随之提高,成为高效晶硅电池科技发展的瓶颈.研究发现,硅中的杂质补偿度和B-O复合体均能造成电池的“光衰”.利用掺镓硅单晶替代掺硼硅单晶并严格控制硅中的杂质补偿度能够大大抑制光衰,其机理和工艺的研究对高效晶硅电池的发展意义重大.     

染料敏化太阳能电池TiO2电极的制备及电解质的影响

采用溶胶-凝胶水热法制备了锐钛矿型纳米晶TiO2薄膜电极,在乙二醇碳酸酯（EC）／1,2-丙二醇碳酸酯（PC）电解液体系中,研究了12和KI含量对电极光电性能的影响,发现随着电解液中12含量的增加,电池的短路光电流呈现先增加后减小的趋势,但光电流增加和减少的幅度并不大,同时体系的暗电流不断增加,光电压不断下降;随着电解液中KI含量的增加,电池的短路光电流也不断增加,当KI的含量大于0．2mol／L时,电池的短路光电流的增加的趋势减缓．并对电解液中I2和KI含量对电池光电性能影响的原因进行了初步的探讨．     

Effect of Intrinsic ZnO Sputtering Parameters on the Cell Efficiency of Cu(In,Ga)Se2 Solar Cells

We investigated the effect of adding oxygen (O₂) gas to argon (Ar) gas and varying the sputter target power during intrinsic ZnO sputtering on the photovoltaic performance of Cu(In,Ga)Se₂ (CIGS) solar cells. Sputtering powers of 50, 100, 150 W were used in conjunction with an O₂ fraction of 0 % or 2 % in the sputtering gas. Both increasing the power and adding oxygen improved the photovoltaic conversion efficiency, although the effect of the latter was more pronounced. The results showed that the open-circuit voltage, short-circuit current density, and fill factor were all improved, and the series resistance was reduced. Electroluminescence spectroscopy and electron-beam-induced current analysis showed that adding oxygen and increasing the power not only improved the CdS/CIGS junction properties, but also the CIGS bulk properties. The current-voltage characteristics at low temperature indicated that adding oxygen and increasing the power facilitated local secondary diode formation around the CIGS surface. It was also revealed that the sodium doping concentration was enhanced by oxygen addition and increased power, with this enhancement being larger for the former. The improvements in the CdS/CIGS junction and CIGS bulk properties were therefore tentatively attributed to an enhancement of the Na doping level.     

Improved Power Conversion Efficiency with Tunable Electronic Structures of the Cation-Engineered [Ai]PbI3 Perovskites for Solar Cells: First-Principles Calculations

Higher power conversion efficiencies for photovoltaic devices can be achieved through simple and low production cost processing of APbI3(A=CH3NH3,CHN2H4,…) perovskites. Due to their limited long-term stability, however, there is an urgent need to find alternative structural combinations for this family of materials. In this study, we propose to investigate the prospects of cation-substitution within the A-site of the APbI3 perovskite by selecting nine substituting organic and inorganic cations to enhance the stability of the material. The tolerance and the octahedral factors are calculated and reported as two of the most critical geometrical features, in order to assess which perovskite compounds can be experimentally designed. Our results showed an improvement in the thermal stability of the organic cation substitutions in contrast to the inorganic cations, with an increase in the power conversion efficiency of the Hydroxyl-ammonium (NH₃OH) substitute to η = 25.84%.     

CaO/MgO摩尔比对太阳能电池封装玻璃性能的影响

利用普通Na2O-CaO-SiO2玻璃体系,通过调整CaO/MgO摩尔比,针对太阳能电池用封装玻璃组分的性能,研究了不同CaO/MgO摩尔比对玻璃软化温度、转变温度、膨胀系数及高低温黏度的影响规律,探讨了不同CaO/MgO摩尔比值对玻璃力学性能的影响。     

Dye-Sensitized Solar Cells Based on the Principles and Materials of Photosynthesis: Mechanisms of Suppression and Enhancement of Photocurrent and Conversion Efficiency

Attempts have been made to develop dye-sensitized solar cells based on the principles and materials of photosynthesis: We first tested photosynthetic pigments, carotenoids (Cars), chlorophylls (Chls) and their derivatives, to find sensitizers showing reasonable performance (photocurrent and conversion efficiency). We then tried to introduce the principles of photosynthesis, including electron transfer and energy transfer from Car to Phe a. Also, we tried co-sensitization using the pheophorbide (Phe) a and Chl c₂ pair which further enhanced the performance of the component sensitizers as follows: J_sc = 9.0 + 13.8 → 14.0 mA cm⁻² and η = 3.4 + 4.6 → 5.4%.     

具有三维多孔结构钛箔表面上液相沉积法制备柔性DSSCs光阳极

用双氧水氧化法将钛箔表面氧化为三维多孔结构,以其为基板,用液相沉积法在氧化后的钛箔表面生长一定厚度的氧化钛膜,并用于柔性染料敏化太阳能电池(DSSCs)光阳极.60℃沉积、烧结、敏化、组装电池后,AM1.5模拟太阳光照下柔性DSSCs的光电转换效率达2.56％.沉积工艺对电池有明显影响,先在80℃沉积再于60℃沉积制备的具有梯度结构的光阳极,其DSSCs光电转换效率达3.09％.     

The Conversion of UDP-Glc to UDP-Man: In Silico and Biochemical Exploration To Improve the Catalytic Efficiency of CDP-Tyvelose C2-Epimerases

A promiscuous CDP-tyvelose 2-epimerase (TyvE) from Thermodesulfatator atlanticus (TaTyvE) belonging to the nucleotide sugar active short-chain dehydrogenase/reductase superfamily (NS-SDRs) was recently discovered. TaTyvE performs the slow conversion of NDP-glucose (NDP-Glc) to NDP-mannose (NDP-Man). Here, we present the sequence fingerprints that are indicative of the conversion of UDP-Glc to UDP-Man in TyvE-like enzymes based on the heptagonal box motifs. Our data-mining approach led to the identification of 11 additional TyvE-like enzymes for the conversion of UDP-Glc to UDP-Man. We characterized the top two wild-type candidates, which show a 15- and 20-fold improved catalytic efficiency, respectively, on UDP-Glc compared to TaTyvE. In addition, we present a quadruple variant of one of the identified enzymes with a 70-fold improved catalytic efficiency on UDP-Glc compared to TaTyvE. These findings could help the design of new nucleotide production pathways starting from a cheap sugar substrate like glucose or sucrose.