The influence of passivation and photovoltaic properties of α-Si:H coverage on silicon nanowire array solar cells

Silicon nanowire (SiNW) arrays for radial p-n junction solar cells offer potential advantages of light trapping effects and quick charge collection. Nevertheless, lower open circuit voltages (V_oc) lead to lower energy conversion efficiencies. In such cases, the performance of the solar cells depends critically on the quality of the SiNW interfaces. In this study, SiNW core-shell solar cells have been fabricated by growing crystalline silicon (c-Si) nanowires via the metal-assisted chemical etching method and by depositing hydrogenated amorphous silicon (α-Si:H) via the plasma-enhanced chemical vapor deposition (PECVD) method. The influence of deposition parameters on the coverage and, consequently, the passivation and photovoltaic properties of α-Si:H layers on SiNW solar cells have been analyzed.     

Recent Progress of Innovative Perovskite Hybrid Solar Cells

Recently, innovative perovskite hybrid solar cells have attracted great interest in solar cell research fields, such as dye-sensitized solar cells, organic photovoltaics, thin-film solar cells, and silicon solar cells, because their device efficiencies are gradually approaching those of crystalline Si solar cells, and they can be fabricated by cheap low-temperature solution processes. Here, we review the recent progress of innovative perovskite hybrid solar cells. The introduction includes the general concerns about solar cells and why we need innovative solar cells. The second part explains the structure and the material properties of hybrid perovskite materials. We focus on why the hybrid perovskite materials can exhibit excellent solar cell properties, such as high open-circuit voltage. The third part introduces recent progress in innovative perovskite hybrid solar cells, in terms of device architecture and deposition methods for dense perovskite thin films with full surface coverage. The device architecture is important in attaining high power conversion efficiency; the device operating mechanism is dependent on the device structure; and the pinhole-free dense perovskite thin films with full surface coverage are crucial for achieving high efficiency. Finally, we summarize the recent progress in perovskite hybrid solar cells, and the issues to be solved, in the summary and outlook section.     

晶体硅太阳能电池背场铝浆研究

研究了晶体硅太阳能电池背场铝浆对电池性能的影响,着重分析了浆料组分对硅铝合金层(P+)电性能的影响,并用光学显微镜表征了背场结构及形貌.结果表明:使用低熔点玻璃粉可以促进硅铝合金层形成；在粗细铝粉比例为2:1时,表面电导率与表面性能最佳；同时,通过加入惰性填料能降低硅片的曲翘度,达到使用要求,相应电池光电转化率为18....     

A novel method for crystalline silicon solar cells with low contact resistance and antireflection coating by an oxidized Mg layer

One of the key issues in the solar industry is lowering dopant concentration of emitter for high-efficiency crystalline solar cells. However, it is well known that a low surface concentration of dopants results in poor contact formation between the front Ag electrode and the n-layer of Si. In this paper, an evaporated Mg layer is used to reduce series resistance of c-Si solar cells. A layer of Mg metal is deposited on a lightly doped n-type Si emitter by evaporation. Ag electrode is screen printed to collect the generated electrons. Small work function difference between Mg and n-type silicon reduces the contact resistance. During a co-firing process, Mg is oxidized, and the oxidized layer serves as an antireflection layer. The measurement of an Ag/Mg/n-Si solar cell shows that V _oc, J _sc, FF, and efficiency are 602 mV, 36.9 mA/cm², 80.1%, and 17.75%, respectively. It can be applied to the manufacturing of low-cost, simple, and high-efficiency solar cells.     

Silicon quantum dot superlattice solar cell structure including silicon nanocrystals in a photogeneration layer

The solar cell structure of n-type poly-silicon/5-nm-diameter silicon nanocrystals embedded in an amorphous silicon oxycarbide matrix (30 layers)/p-type hydrogenated amorphous silicon/Al electrode was fabricated on a quartz substrate. An open-circuit voltage and a fill factor of 518 mV and 0.51 in the solar cell were obtained, respectively. The absorption edge of the solar cell was 1.49 eV, which corresponds to the optical bandgap of the silicon nanocrystal materials, suggesting that it is possible to fabricate the solar cells with silicon nanocrystal materials, whose bandgaps are wider than that of crystalline silicon.

PACS

85.35.Be; 84.60.Jt; 78.67.Bf     

晶体硅太阳能电池用微细银粉制备研究进展

太阳能光伏发电是世界各国大力发展的战略新兴产业,目前中国太阳电池组件产量位居世界首位,但许多高附加值的太阳能电池材料如导电银浆长期依赖进口,而微细银粉是太阳能电池导电银浆的重要组成部分。中国关于太阳能电池导电银浆和银粉的研究报道很多,发明专利申请数量庞大,但均未涉及产业化开发情况。分别介绍了晶体硅太阳能电池电极银浆用微细银粉的质量要求、制备方法和技术关键,综述了化学还原法制备微细银粉用还原剂、分散剂和形貌控制方法的研究进展,并提出了存在的问题和改进方向,以拓宽太阳能电池导电银浆技术开发人员的研究思路。     

Electrochemical photovoltaic cells—review of recent developments

Photoelectrochemistry is attracting extensive attention from scientists worldwide for its use in converting light energy into electricity in electrochemical photovoltaic cells, the most common form of which, dye sensitized solar cells (DSSCs), can offer both flexibility and transparency. Their efficiencies are now comparable with amorphous silicon solar cells but at a much lower cost. This review covers not only the fundamentals of electrochemical photovoltaic cell operation but also recent advances in research and development for industrial applications. The most recent research topics relating to DSSCs, for example, applications of nanostructured n‐type semiconducting electrodes, ionic liquid electrolytes and graphene and carbon nanotube electrodes are all included. In addition, the storage of electrochemical energy by electrochemical photovoltaic cells has also been reviewed. Copyright © 2010 Society of Chemical Industry     

太阳能光伏产业智能化开发及应用

近年来,中国建材国际工程集团有限公司充分利用自身在太阳能光伏产业链全覆盖的优势,结合其在基础材料、组件、装备等方面取得的技术突破,从研发(晶硅、碲化镉薄膜、铜铟镓硒薄膜)、智能装备制造、设计、建造(光伏工厂、光伏电站等)、运维和管理等方面对公司的光伏产业进行了全方位智能化升级,并将相关成果应用于国内外多个重点光伏项目中。这对于推动我国光伏产业高质量发展,尤其是智能光伏产业技术进步起到积极示范作用。     

Recent trends in polymer tandem solar cells research

Polymer solar cells have many intrinsic advantages, such as their light weight, flexibility, and low material and manufacturing costs. Recently, polymer tandem solar cells have attracted significant attention due to their potential to achieve higher performance than single cells. This trend article intends to provide the latest progress in polymer tandem solar cell technology with a focus on active layer materials and interfacial materials for sub-cell interconnection. Following an introduction of the structure and current status of polymer tandem solar cells, this article will review polymers which have been, and could be used, for tandem solar cells. Furthermore, this article will discuss the interconnecting layer consisting of p- and n-type interfacial layers, which is equally critical for polymer tandem solar cells. Finally, because tandem solar cell measurements are more complicated than that of single solar cells, this article will also address polymer tandem solar cell measurement issues.     

Verfahren zur Herstellung von Solarsilicium

Production of solar silicon. Economic exploitation of solar energy using solar cells made of crystalline silicon is dependent upon a considerable drop in the cost of the silicon raw material which is nowadays produced by standard methods of the semiconductor industry. New procedures for producing less expensive solar silicon can be divided into four groups characterized by different physico-chemical purification techniques: (1) reduction of volatile Si-H-Cl compounds; (2) purification of technical grade silicon (98–99%); (3) reduction of hexafluorosilicates; (4) reduction of silicon dioxide. Among the ten solar silicon processes under discussion, the purification of technical grade silicon and the carbothermal reduction of silicon dioxide have the greatest scope for cost reduction; however, it remains to be established whether the necessary purity can be achieved on an industrial scale.     

碳中和目标下的光伏发电技术

化石能源燃烧发电过程是我国CO₂排放的主要来源之一。在碳中和、碳达峰的“双碳”目标下,大力发展可再生能源等低碳或零碳能源体系,构建以新能源为主体的新型电力系统,成为能源领域技术变革的战略方向,其中光伏发电是公认的我国未来可再生能源发电的主要方式之一。本文重点对我国光伏发电的开发现状、存在问题、关键技术、未来趋势及发展策略等进行简要论述,分别对晶硅太阳能电池、薄膜太阳能电池（硅基、砷化镓、铜铟镓硒、碲化镉）、钙钛矿太阳能电池、其他新型太阳能电池（有机、染料敏化、量子点）等关键技术进行了详细论述,以期为我国光伏发电产业的快速发展及高效安全的清洁能源新体系构建提供方向引导。     

Dye-Sensitized Tandem Solar Cells with Extremely High Open-Circuit Voltage Using Co(II)/Co(III) Electrolyte

For achieving a high open-circuit voltage (V_oc) in dye-sensitized tandem solar cells, series-connected tandem solar cells were fabricated. In order to optimize series-connected tandem solar cell systems, the current density of the top and bottom cells should be well matched to be identical, and the V_oc of each of the cells should also be as high as possible. Furthermore, the top cell should be transparent and the bottom cell should have the longer-wavelength absorption, for utilizing only the light passing through the top cell. This leads to a high V_oc. In this study, we report dye-sensitized tandem solar cells having an extremely high V_oc using the Co(bpy)₃^2+/3+ (bpy=2,2′-bipyridine) redox couple. Dye-sensitized tandem solar cells employing JK303/HC-A1 with the Co(bpy)₃^2+/3+ redox couple as the top cell and N749/HC-A4 with the I⁻/I₃⁻ redox couple as the bottom cell were shown to have an extremely high V_oc of >1.66 V, the highest value for dye-sensitized tandem solar cells reported to date.     

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。     

染料敏化太阳电池中电解质的研究进展

作为新一代的太阳能电池染料敏化太阳电池应用前景广阔,而电解质体系是该类电池重要组成部分,对电池性能有着重要的影响。文章对染料敏化太阳电池中的电解质研究进行了综述,根据电解质的类型将染料敏化太阳电池分为液体电解质电池、溶胶-凝胶(准固态)电解质电池和固态电解质电池,分析了这三种太阳电池的优缺点,并对其前景进行展望。     

Design,Optimization and Characterisation of IBC c-Si (n) Solar Cell

The integrated-back contact (IBC) solar cell has attracted wide attention due to its high conversion efficiency, low processing temperature, and thinner substrate from the emerging light trapping of silicon on the pyramidal textured surface. In this paper, a novel IBC solar cell design optimization based on the n-type crystalline silicon wafer was simulated in 2D using Silvaco TCAD tools and the obtained results were compared to the recently published works which allow us to identify the optimum IBC solar cell configuration. In addition, the 2D simulation results are compared to the obtained results by IMEC using SolayTec’ ALD (atomic layer deposition) technique. The numerical simulation leads to attaining 24.79% conversion efficiency and 726 mV open-circuit voltage for the considered n-type mono-crystalline silicon solar cell under the AM1.5 spectrum.     

光敏染料在Gr(a)tzel型太阳能电池上的应用及其研究进展

对光敏染料在Gratzel型太阳能电池上的应用及其研究进展进行了综述.比较了天然染料、纯有机染料和金属有机配合物染料对此类电池的敏化效果,并讨论了染料的结构和性质对电池性能的影响,指出通过分子设计合成高效光敏染料可推动Gratzel型太阳能电池的发展和实用化.     

Hybrid morphology dependence of CdTe:CdSe bulk-heterojunction solar cells

A nanocrystal thin-film solar cell operating on an exciton splitting pattern requires a highly efficient separation of electron-hole pairs and transportation of separated charges. A hybrid bulk-heterojunction (HBH) nanostructure providing a large contact area and interpenetrated charge channels is favorable to an inorganic nanocrystal solar cell with high performance. For this freshly appeared structure, here in this work, we have firstly explored the influence of hybrid morphology on the photovoltaic performance of CdTe:CdSe bulk-heterojunction solar cells with variation in CdSe nanoparticle morphology. Quantum dot (QD) or nanotetrapod (NT)-shaped CdSe nanocrystals have been employed together with CdTe NTs to construct different hybrid structures. The solar cells with the two different hybrid active layers show obvious difference in photovoltaic performance. The hybrid structure with densely packed and continuously interpenetrated two phases generates superior morphological and electrical properties for more efficient inorganic bulk-heterojunction solar cells, which could be readily realized in the NTs:QDs hybrid. This proved strategy is applicable and promising in designing other highly efficient inorganic hybrid solar cells.     

A Mathematical Model for the Design and Fabrication of Polymer Solar Cells by Spray Coating

Spraying of solution-processable materials such as organic molecules, polymers, nanoparticles, and quantum dots is a viable candidate for the coating process and fabrication of thin film solar cells and other similar semiconductor devices. Spray coating, similar to spray painting in the automotive industry, is a fast process and can be scaled up and used for the roll-to-roll fabrication of solar panels. In this paper, attempts are made to understand various steps of the process and develop a simple model as a design tool. The model equations are solved numerically for the spray coating of a P3HT-PCBM active layer in a polymer solar cell using ultrasonic atomization to investigate the effect of process parameters on the thin film characteristics, such as the film thickness and heat consumption needed to vaporize the solvent. It is concluded that when using spray coating with a small thermal budget, large areas with desired submicron- and nanometer-sized thicknesses can be made in a fast process. Cost of thermal energy and materials decreases with an increase in the substrate speed and nozzle-substrate distance.     

Controlled synthesis of various ZnO nanostructured materials by capping agents-assisted hydrothermal method for dye-sensitized solar cells

In this work, the morphology of ZnO materials could be controlled by changing the capping agent at constant alkali solution in hydrothermal process. ZnO nanomaterials with the structure of flowers, sheet-spheres and plates were obtained with the capping agent of ammonia, citric acid and oxalic acid, respectively. Thus prepared ZnO nanomaterials were characterized and applied as the photo-anode materials for dye-sensitized solar cell. All synthesized ZnO nanomaterials possessed high crystalline wurtzite structures grown in the (0 0 1) direction with the size of 2-4 μm, which consist of ZnO units around 20-400 nm. Among them, Sheet-sphere ZnO showed the highest crystallinity, surface area and uniform film morphology, resulting in the significantly improved PV performance with the overall conversion efficiency of 2.61% in dye-sensitized solar cell (DSSC) fabricated with sheet-sphere ZnO. It is notable that the ZnO materials with sphere structure may be the optimal photo-anode material among various ZnO nanomaterials for DSSC.     

Performance assessment of multijunction solar cells incorporating GaInNAsSb

We have measured the characteristics of molecular beam epitaxy grown GaInNAsSb solar cells with different bandgaps using AM1.5G real sun illumination. Based on the solar cell diode characteristics and known parameters for state-of-the-art GaInP/GaAs and GaInP/GaAs/Ge cells, we have calculated the realistic potential efficiency increase for GaInP/GaAs/GaInNAsSb and GaInP/GaAs/GaInNAsSb/Ge multijunction solar cells for different current matching conditions. The analyses reveal that realistic GaInNAsSb solar cell parameters, render possible an extraction efficiency of over 36% at 1-sun AM1.5D illumination.

PACS

88.40.hj; 88.40.jm; 88.40.jp; 81.15.Hi