一种新的太阳能光电转换装置

据英国 Nature,2003,421:586报道,美国科学家最近发明了一种新的非硅太阳能光电转换装置。这个装置具有多层结构,最上一层是一种染料分子用来吸收光子,它们吸附在一层金膜的表面,然后是一层二氧化钛(TiO_2)半导体,最后一层是二氧化钛载体。金膜和二氧化钛半导体之间存在一个自发生成的局域电场,这个局域电场产生一个电势势垒。

一种适用于牧区的新型太阳能系统

青藏高原太阳能资源丰富,海拔高,气温低,人烟稀少,常规能源稀缺,饮水,用气等生活必须较为困难.针对这一情况,设计了一种适用于高原牧区的新型太阳能系统,该系统将太阳能光电转换技术和太阳能集热技术综合利用,在发出电的同时,还能为牧民提供热水,饮用水.同时,光热、光电系统的集成大大提高了系统的综合效率,让光伏板在处于温度频繁突变的不利工作环境下也能正常工作.实验结果验证了该系统的有效性.

太阳能减噪结合板在建筑室外遮阳百叶中的应用研究

将太阳能光电转换板与PVC减噪孔板结合应用于建筑遮阳百叶中,在改善建筑光环境的同时对建筑声环境与能耗有所改善。在已有建筑中,将太阳能光电转换板与PVC减噪孔板结合构成建筑遮阳百叶的叶片,在保证系统遮阳性能的条件下,与原有建筑对比测试,分析太阳能减噪结合板节能效益和减噪性能。通过对比遮阳板设置前后得到太阳能减噪结合板的节能效益,发现在北京地区在一定的设计结构下,每使用100 m^2太阳能光电转换板能节约1.52吨标准煤,减噪板能减少10%～20%的室内噪音。一定结构的太阳能减噪结合板遮阳百叶可减少夏季进入室内的阳光,能保证冬季必要日照的同时减少进入建筑室内的噪音;结构简单,耐用,可减少建筑供暖和空调的冷热负荷,节约能源。

移动机器人能源自治研究与进展

针对国内外目前研究现状,主要介绍了实现移动机器人能源自治的方法.重点分析了基于太阳能的机器人能源自治系统组成,并分析了跟踪机构,太阳能光电转换,蓄电池充、放电等关键技术.结合现有实现方法的特点,探讨了移动机器人基于太阳能的能源自治发展趋势.

焊接发展的几个新方向-新材料、新能源和信息化制造

本文简述了焊接发展的几个新方向：新材料、新能源和信息化制造,阐述了如何把焊接冶金材料变成新能源材料,如何把太阳能用于焊接和做成焊接工程车,如何把焊接一次堆焊成形变为三维的信息化增材制造、减材制造和分离制造。这些技术都是焊接人比较熟悉的技术,如用以改造我们的焊接材料、焊接设备和焊接工艺,必将大有可为。

形形色色的电冰箱

冰箱自从问世以来,一直不断有新产品推出。时至今日一些国家仍不断研制出冰箱新产品: ●不用电的冰箱。由瑞士研制。它既无电动机,又无压缩机,是利用氨气进行工作的。氨气在小压力下能被冷水所吸收,而在温度上升时又能从水里挥发出来,同时吸收大量的热能,从而能保持低温。 ●太阳能冰箱。由英国制造。它是利用太阳能光电转换的冰箱,其内装9片面积为3×2英尺的光电极,在全日照条件下可产生12伏、2安电流。

Optimization with Genetic Algorithms of PVT System Global Efficiency

PV （photovoltaic） solar panels generally produce electricity in the 6% to 12% efficiency range, the rest is being dissipated in thermal losses. To recover this amount, hybrid photovoltaic thermal systems （PV/T） have been devised. These are devices that simultaneously convert solar energy into electricity and heat. It is thus interesting to study the PV/T system as part of a closed loop single phase water CDU （coolant distribution unit） in laminar forced convection. In particular, the analysis was conducted on the optimal cooling performance of the thermal part, testing polynomial channel profiles of varying order （from zero to fourth） for channels of a real industrial module heat sink, under the following conditions： ideal flux of 1,000 W/m2 on one side, insulation on the opposite side, periodic conditions on the remaining sides, fully developed thermal and velocity profile in laminar flow of water. Through the use of a genetic algorithm, we have optimized the shape of the channel＇s sidewalls in terms of heat transfer maximization. In terms of Nusselt number, results show that fourth order profiles are the most efficient. When limits to allowable pressure loss and module weight are introduced, these bring generally to a lower efficiency of the system than the unconstrained case.

Design of High Efficiency DC-DC Converter for Photovoltaic Solar Home Applications

The solar energy conversion system is very interesting alternative on supplement the electric system generation, due to the persistent cost reduction of the overall system and cleaner power generation. To obtain a stable voltage from an input supply （PV cells） that is higher and lower than the output, a high efficiency and minimum ripple DC-DC converter required in the system for residential power production. Buck-boost converters make it possible to efficiently convert a DC voltage to either a lower or higher voltages. Buck-boost converters are especially useful for PV maximum power tracking purposes, where the objective is to draw maximum possible power from solar panels at all times, regardless of the load. This paper analyzes and describes step by step the process of designing, and simulation of high efficiency low ripple voltage buck-boost DC-DC converter for the photovoltaic solar conversion system applicable to a （typical） single family home based on battery-based systems. The input voltage can typically change from （20 V） initially, down to （5 V）, and provide a regulated voltage within the range of the battery （12 V）. PLECS simulation results provide strong evidences about the high efficiency, minimum ripple voltage, high accuracy, and the usefulness of the system of the proposed converter when applied to either residential or solar home applications.

Method of 3D Solar Energy Conversion

The problem of collecting solar energy and increasing its efficiency was studied in this paper. It was discovered that a 3DPV （three-dimensional photovoltaic） structures can generate greater amounts of measured energy densities than stationary flat PV panels （rate： 2 to 20）. It has been found that the same structures work better not only because they are made in 3D but because PV panels do not have linear dependency on geometry. It seems that the conversion efficiency depends on the process of absorption of the solar energy, too, or in other words on the E. Yablonovich limit. The findings suggest that the quantity of material of solar panels may be reduced to generate the same amount of electricity.

High Frequency Transformers for DC/DC Converter Used in Solar PV System

This paper presents and investigates planar and coaxial high frequency power transformers used for DC/DC converters in a three phase photo voltaic （PV） power systems. The winding structure including a Faraday shield between the primary and secondary windings is designed to minimize eddy current losses, skin and proximity effects, and to reduce the leakage inductance, and the inter winding coupling capacitance. Finite Element Method is employed to analyze the magnetic flux and eddy current distributions. The two different kinds of prototype high frequency transformers are designed and tested. The simulation and experiment results are demonstrated and compared with non-shielded transformers. The shielded transformers have achieved the expected results with a relatively small coupling capacitance, compared with the conventional high frequency transformer. This shield decreases the inter-winding coupling capacitance Cps. The topology of this shield has to be such that it acts as a Faraday screen while avoiding eddy current generation.

New D-π-A dyes for efficient dye-sensitized solar cells

Functional organic dyes have promising prospect in dye-sensitized solar cells as a crucial element, of which sensitizers based on donor-π-acceptor are the most important dyes. On the basis of the structures of the aromatic amine donors such as triphenylamine and indoline, this paper reviews the photoelectric conversion properties of organic sensitizers since 2008, and highlights research work in our laboratory in this area.

Manipulate energy transport via fluorinated spacers towards recordefficiency 2D Dion-Jacobson CsPbI_(3) solar cells

Two-dimensional(2D)Dion-Jacobson(D-J)-type cesium lead iodide CsPbI_(3) perform remarkably in terms of stability.However,the complex interactions between spacer and inorganic layers limit its excellent progress in perovskite solar cells(PSCs).Herein,starting from the considerable structural diversity of organic spacers,we engineer 2D CsPbI_(3) with fine-tuning functionalities.Specifically,for the first time we embedded fluorinated aromatic cations in 2D D-J CsPbI_(3),and successfully applied it into construction of high-performance PSCs.Compared with constitutive 1,4-diaminobenzene(PDA),the fluorinated 2-fluorobenzene-1,4-diamine(F-PDA)component greatly expands the dipole moment from 0.59 D to 3.47 D,which reduces the exciton binding energy of the system.A theoretical study shows that the spacer layer and inorganic plane are more enriched with charge accumulation in(F-PDA)Csn±1 Pb_(n)I_(3n+1).The results show that(F-PDA)Csn±1Pb_(n)I_(3n+1) demonstrates more significant charge transfer between organic and inorganic layers than(PDA)Csn±1 Pb_(n)I_(3n+1),and it is confirmed in the femtosecond transient absorption experiment.Moreover,the interactions of the fluorinated spacer with the[PbI_(6)]_(4)-plane effectively manipulate the crystallization quality,and thus the ion migration and defect formation of target 2D CsPbI_(3) are inhibited.As a result,we obtained a record power conversion efficiency(PCE)beyond 15%for 2D D-J(F-PDA)Cs_(3)Pb_(4)I_(13)(n=4)PSCs with significantly improved environmental stability compared with the three-dimensional(3D)counterparts.

Grain boundary passivation with triazine-graphdiyne to improve perovskite solar cell performance

Detrimental defects on perovskite grain boundaries(GBs)are critical factors that lead to non-radiative recombination and hysteresis.In this work,triazine-graphdiyne(Tra-GD),a nitrogen-rich two-dimensional(2 D)material,was incorporated into the active layer of perovskite to modify the GBs.Tra-GD was found to distribute evenly over the bulk of the perovskite and has a strong interaction with the Pb^2+ exposed at GBs,which enables it to effectively passivate GB defects and prevent ion migration.The results of Kelvin probe force microscopy and photoluminescence studies proved that the highly conjugated Tra-GD located at GBs could promote charge extraction and transport.Benefiting from defect passivation and more efficient carrier transport,the Tra-GD based device showed less non-radiative recombination loss.Consequently,the resultant device presented negligible hysteresis and yielded a high power conversion efficiency(PCE)of 20.33%in the MAPbI3-based perovskite solar cell.This approach was extended to the FAPbI3 system with a PCE of 21.16%.Our Tra-GD passivation strategy provides a useful approach to effectively improving the device performance and addressing hysteresis issues.

Interfacial stabilization for inverted perovskite solar cells with long-term stability

Perovskite solar cells(PSCs)commonly exhibit significant performance degradation due to ion migration through the top charge transport layer and ultimately metal electrode corrosion.Here,we demonstrate an interfacial management strategy using a boron chloride subphthalocyanine(Cl_(6)SubPc)/fullerene electron-transport layer,which not only passivates the interfacial defects in the perovskite,but also suppresses halide diffusion as evidenced by multiple techniques,including visual element mapping by electron energy loss spectroscopy.As a result,we obtain inverted PSCs with an efficiency of 22.0%(21.3%certified),shelf life of 7000 h,T_(80) of 816 h under damp heat stress(compared to less than 20 h without Cl_(6)SubPc),and initial performance retention of 98%after 2000 h at 80℃in inert environment,90%after 2034 h of illumination and maximum power point tracking in ambient for encapsulated devices and 95%after 1272 h outdoor testing ISOS-O-1.Our strategy and results pave a new way to move PSCs forward to their potential commercialization solidly.

A low-temperature TiO2/SnO2 electron transport layer for high-performance planar perovskite solar cells

Conventional titanium oxide(TiO2) as an electron transport layer(ETL) in hybrid organic-inorganic perovskite solar cells(PSCs) requires a sintering process at a high temperature to crystalize, which is not suitable for flexible PSCs and tandem solar cells with their low-temperatureprocessed bottom cell. Here, we introduce a low-temperature solution method to deposit a TiO2/tin oxide(SnO2) bilayer towards an efficient ETL. From the systematic measurements of optical and electronic properties, we demonstrate that the TiO2/SnO2 ETL has an enhanced charge extraction ability and a suppressed carrier recombination at the ETL/perovskite interface, both of which are beneficial to photo-generated carrier separation and transport. As a result, PSCs with TiO2/SnO2 bilayer ETLs present higher photovoltaic performance of the baseline cells compared with their TiO2 and SnO2 single-layer ETL counterparts. The champion PSC has a power conversion efficiency(PCE) of 19.11% with an open-circuit voltage(Voc)of 1.15 V, a short-circuit current density(Jsc) of 22.77 mA cm^-2,and a fill factor(FF) of 72.38%. Additionally, due to the suitable band alignment of the TiO2/SnO2 ETL in the device, a high Vocof 1.18 V is achieved. It has been proven that the TiO2/SnO2 bilayer is a promising alternative ETL for high efficiency PSCs.

Stable tin perovskite solar cells enabled by widening the time window for crystallization

Tin perovskite solar cells (TPSCs) are the most promising candidates for lead-free perovskite solar cells(PSCs).However,the poor crystallization and chemical stability of Sn perovskites are the two challenging issues for further application of TPSCs.Here,we present a strategy to stabilize CH(NH_(2))2SnI3(FASnI3) perovskite enabled by an amine complex,CH3NH3I·3CH3NH_(2),which can hinder the major degradation issue caused by the oxidation of Sn2+to Sn4+.The resulting Sn perovskite films exhibit enhanced crystallinity and stability in comparison with those made with conventional inorganic SnF2 additives.Finally,the device achieved a higher external quantum efficiency for charge extraction and a power conversion efficiency (PCE) of 9.53%,which maintained more than 90%of the initial efficiency after1000 h of light soaking under the standard AM 1.5 G solar illumination.

Tailoring organic bulk-heterojunction for charge extraction and spectral absorption in CsPbBr perovskite solar cells

All-inorganic CsPbBr_(3)perovskite solar cells(PSCs)are promising candidates to balance the stability and efficiency issues of organic-inorganic hybrid devices.However,the large energy barrier for charge transfer and narrow spectral response are still two challenging problems for performance improvement.We present here an organic bulkheterojunction{poly(3-hexylthiophene-2,5-diyl):[6,6]-phenyl C61 butyric acid methyl ester(P3HT:PCBM)}photoactive layer to boost the charge extraction and to widen the spectral absorption,achieving an enhanced power conversion efficiency up to 8.94%by optimizing the thickness of P3HT:PCBM photoactive layer,which is much higher than 6.28%for the pristine CsPbBr_(3)device.The interaction between the carbonyl group in PCBM and unsaturated Pb atom in the perovskite surface can effectively passivate the defects and reduce charge recombination.Furthermore,the coupling effect between PCBM and P3HT widens the spectral response from 540 to 650 nm for an increased short-circuit current density.More importantly,the devices are relatively stable over 75 days upon persistent attack by 70%relative humidity in air condition.These advantages of high efficiency,excellent long-term stability,cost-effectiveness and scalability may promote the commercialization of inorganic PSCs.

Stable tin perovskite solar cells developed via additive engineering

Tin perovskite solar cells(TPSCs)are promising for lead-free perovskite solar cells(PSCs)and have led to extensive research;however,the poor crystallinity and chemical stability of tin perovskites are two issues that prevent stable TPSCs.In this study,we outline a new process that addresses these issues by using tin(II)acetate(Sn(Ac)2)in place of the conventional SnF2 precursor additive.Compared with SnF2,Sn(Ac)2 improves the crystallinity and stability of tin perovskite with fewer defects and better charge extraction.Using this process,we developed a device that has a higher external quantum efficiency for charge extraction compared with the control devices and a power conversion efficiency of 9.93%,which maintained more than 90%of its initial efficiency after 1000 h operation at the maximum power point under standard AM 1.5G solar illumination.

Graphdiyne oxide-accelerated charge carrier transfer and separation at the interface for efficient binary organic solar cells

Interfacial engineering for the regulation of the charge carrier dynamics in solar cells is a critical factor in the fabrication of high-efficiency devices.Based on the successful preparation of highly dispersible graphdiyne oxide(GDYO)with a large number of functional groups,we fabricated organic solar cells employing GDYO-modified poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate)(PEDOT:PSS)as hole transport materials.Results show that theπ±πinteraction between GDYO and PEDOT:PSS is beneficial to the formation of an optimized charge carrier transfer channel and improves the conductivity and charge carrier mobility in the hole transport layer.Moreover,the improved interfacial contact contributes to the suppression of charge carrier recombination and the elevation of charge carrier extraction between the hole transport layer and the active layer.More importantly,the occurrence of charge carrier separation benefits from the optimized morphology of the active layer,which efficiently improves the performance,as proven by the results of transient absorption measurements.Therefore,with the holistic management approach to the multiobjective optimization of the charge carrier dynamics,a photoelectric conversion efficiency of 17.5%(with the certified value of 17.2%)is obtained for binary organic solar cells.All of these results indicate the potential application of the functionalized graphdiyne in the field of organic optoelectronic devices.