Efficient and stable planar all-inorganic perovskite solar cells based on high-quality CsPbBr3 films with controllable morphology

All-inorganic cesium lead bromide(CsPbBr3)perovskite is attracting growing interest as functional materials in photovoltaics and other optoelectronic devices due to its superb stability.However,the fabrication of high-quality CsPbBr3 films still remains a big challenge by solution-process because of the low solubility of the cesium precursor in common solvents.Herein,we report a facile solution-processed approach to prepare high-quality CsPbBr3 perovskite films via a two-step spin-coating method,in which the Cs Br methanol/H2 O mixed solvent solution is spin-coated onto the lead bromide films,followed by an isopropanol-assisted post-treatment to regulate the crystallization process and to control the film morphology.In this fashion,dense and uniform CsPbBr3 films are obtained consisting of large crystalline domains with sizes up to microns and low defect density.The effectiveness of the resulting CsPbBr3 films is further examined in perovskite solar cells(PSCs)with a simplified planar architecture of fluorine–doped tin oxide/compact Ti O2/CsPbBr3/carbon,which deliver a maximum power conversion efficiency of 8.11%together with excellent thermal and humidity stability.The present work offers a simple and effective strategy in fabrication of high-quality CsPbBr3 films for efficient and stable PSCs as well as other optoelectronic devices.

Atmospheric stable and fexible Sn-based perovskite solar cells via a bioinspired antioxidative crystal template

Sn-based perovskite solar cells(PSCs)demonstrate a potential development in eco-friendly devices due to their hypotoxicity.However,poor stability and crystalline quality are still the challenges for achieving high-performance and long-term operating devices.In this work,inspired by biological protein,nickelporphyrin(Ni-P)with electron cloud on conjugate ring is applied into Sn-based perovskite to prevent perovskite from being eroded.The synergistic effect of water and oxygen is broken in grain boundaries and surface so that the stability of PSCs can be improved obviously,despite there is hardly any barrier for water to erode.Simultaneously,the electron-rich molecules can passivate the defects of perovskite such as iodine vacancy.Moreover,the ester group in Ni-P molecule can bind with SnI;to form complex and then restrain nucleation.Combining with the template effect of 2D molecular,the crystallization of perovskite films is optimized.Therefore,the Sn-based PSCs with Ni-P achieve a stabilized power conversion efficiency(PCE)of 7.79%with negligible hysteresis in fexible devices,respectively.Moreover,the PSCs can maintain 80%of the pristine PCE after 300 h under air environment.

Real-Time Implementation of Solar Inverter with Novel MPPT Control Algorithm for Residential Applications

Solar energy is a fast growing energy resource among the renewable energy resources in the market and potential for solar power is huge to contribute towards the power demand almost in all the countries. To capture the maximum power from the sun light in order to generate maximum power from the inverter, control system must be an equally efficient with the well designed power electronic circuits. Maximum power point tracking (MPPT) control system in general is taking care of extraction of maximum power from the sun light whereas current controller is mainly designed to optimize the inverter power to feed to power grid. In this paper, a novel MPPT algorithm using neuro fuzzy system is presented to ensure the maximum MPPT efficiency in order to ensure the maximum power across the inverter terminals. Simulation and experimental results for residential solar system with power electronic converters and analysis have been presented in this paper in order to prove the proposed algorithm.

Photoactive area modification in bulk heterojunction organic solar cells using optimization of electrochemically synthesized ZnO nanorods

In this work, ZnO nanorod arrays grown by an electrochemical deposition method are investigated. The crucial parameters of length, diameter, and density of the nanorods are optimized over the synthesize process and nanorods growth time. Crystalline structure, morphologies, and optical properties of ZnO nanorod arrays are studied by different techniques such as x-ray diffraction, scanning electron microscope, atomic force microscope, and UV-visible transmission spectra. The ZnO nanorod arrays are employed in an inverted bulk heterojunction organic solar cell of Poly （3-hexylthiophene）：[6- 6] Phenyl-（6） butyric acid methyl ester to introduce more surface contact between the electron transporter layer and the active layer. Our results show that the deposition time is a very important factor to achieve the aligned and uniform ZnO nanorods with suitable surface density which is required for effective infiltration of active area into the ZnO nanorod spacing and make a maximum interfacial surface contact for electron collection, as overgrowing causes nanorods to be too dense and thick and results in high resistance and lower visible light transmittance. By optimizing the thickness of the active layer on top of ZnO nanorods, an improved efficiency of 3.17% with a high FF beyond 60% was achieved.

大面积有机–无机杂化钙钛矿薄膜及其光伏应用研究进展

有机–无机杂化钙钛矿太阳能电池具有制备成本低、光电转换效率(Photoelectric Conversion Efficiency,PCE)高的巨大优势,显示出广阔的商业化前景。经过十几年的深入研究,钙钛矿太阳能电池(Perovskite Solar Cells,PSCs)的实验室器件(<1 cm^(2))、大面积器件(1~10 cm^(2))、迷你模组级器件(10~800 cm^(2))和模组级器件(>800 cm^(2))的最高认证PCE已分别提升至26.10%、24.35%、22.40%和18.60%。随着PSCs面积扩大,PCE急剧下降,这主要是因为制备方法的局限性,难以获得高质量的大面积钙钛矿薄膜。实验室器件常采用的旋涂法难以应用到实际生产中,目前大面积钙钛矿薄膜的制备方法主要有刮涂法和狭缝涂布法,但其存在薄膜成核结晶过程难以精确控制等问题。本文从大面积有机–无机杂化钙钛矿薄膜的制备方法入手,介绍了大面积钙钛矿层成膜机制及薄膜质量提升策略。最后,对未来高PCE、高稳定性的大面积PSCs的制备技术和应用进行了展望,旨在对高性能的大面积PSCs研究提供有益参考。

双堆燃料电池热管理系统自抗扰控制

为对双堆燃料电池热管理系统进行有效控制,基于试验数据建立了电堆模型,并耦合水泵、换热器等关键零部件模型形成完整的热管理系统模型。为保证阶跃工况下电堆温度的稳定,设计了基于比例积分与线性自抗扰算法的联合控制策略,并进行仿真验证。提出了基于前馈解耦及串级LADRC的改进控制策略,通过仿真对比改进前后的控制效果。结果表明,改进后的控制策略能有效减小超调量,反映温控精度的时间乘绝对误差积分量最高可降低66.39%。

硼扩散设备温度控制系统的研究与实现

近年来,随着光伏行业持续快速的发展,n型TOPCon太阳电池技术路线得到市场认可,产能不断扩张。硼扩散设备作为TOPCon太阳电池核心工艺设备之一受到市场极大的关注,其温度控制系统在工艺生产过程起着决定性的作用。对比硼扩散设备实际应用过程中传统炉体使用水平插片方式和顺气流垂直插片方式后得到的硅片片间的方阻均匀性,发现水平插片方式存在舟内中层硅片方阻偏高,方阻均匀性不满足技术性指标要求的问题。对此设计了新型分区炉体,提出3种温度控制系统方案,并通过工艺验证得出满足技术性指标要求的方案。研究结果表明:分区炉体搭配水平插片方式时,采用温度控制系统方案3可以满足技术性指标的要求。

钙钛矿太阳电池测量中的温控方案研究

高效钙钛矿太阳电池的测量需求日益提升,已成为光伏界的主要研究热点之一。其关键电性能(特别是转换效率)一般使用稳态太阳模拟器、平板式温控平台和相应电测系统。在1个太阳常数光强的照射下,样品的精确温控是关键电参数准确测量的必要条件。本文介绍了一种针对其关键电性能测量的温控装置,并对不同的电性能测量结果进行分析。实验表明:该装置具有优越的性能,为测量者依据相关国际标准进行可复现测量提供了新方案。

Realization of high performance for PM6:Y6 based organic photovoltaic cells

With advances in material science and a more in-depth understanding of device engineering,the power conversion efficiency(PCE)of solution-processed organic photovoltaic(OPV)cells have significantly boosted in the past few years.In 2019,a high PCE of 15.7%was achieved in the OPV cells adopting a wide bandgap polymer PM6 and a new emerging non-fullerene acceptor Y6.Such outstanding performance has attracted lots of research attention,driving considerable efforts to improve or take advantage of the high-performance PM6:Y6-based system.In this review,we first concentrate on the structural characteristics of PM6 and Y6 with the focus on understanding why their combination for OPV application can obtain such high efficiency.We also update the recent progress in highly efficient PM6:Y6-based OPV cells via various optimizing strategies.Then we summarize the other applications of the PM6:Y6-based system in semi-transparent,flexible or lay e-by-layer devices.The prospects for future OPV studies will be suggested in the end.

Modeling, Control &Fault Management of Microgrids

In this paper, modeling and decentralize control principles of a MicroGrid (MG) whom equipped with three Distributed Generation (DG) systems (consist of: Solar Cell System (SCS), MicroTurbine System (MTS) and Wind Energy Conversion System (WECS)) is simulated. Three arrangement of load changing have investigated for the system. In first one the system doesn’t have transfer of power between MG and grid. In other two arrangements system have transfer of power between MG and utility grid. Of course in third case transfer of power between DG resources is considerable. Case study system is equipped by energy storage devices (battery bank) for each DG’s separately by means of increasing the MG reliability. For WECS and SCS, MPPT control and for MTS, voltage and frequency (V&F) controller has designed. The purpose of this paper is load respond in MG and storage process of surplus energy by consider of load changing. MATLAB/Simulink and its libraries (mainly the Sim Power Systems toolbox) were employed in order to develop a simulation platform suitable for identifying MG control requirements. This paper reported a control and op- eration of MG in network tension by applying a three phase fault.

基于改进灰狼优化算法的光伏阵列多峰MPPT研究

针对局部阴影条件下光伏阵列呈现出的非线性多峰值P-V输出特性,提出一种基于改进灰狼优化算法的最大功率点跟踪(MPPT)控制方法。该算法将传统灰狼优化算法中线性减小的收敛因子改进为按非线性规律变化,以改善算法的动态性能。结果表明:所提出的MPPT方法在局部阴影条件下能有效跟踪到光伏阵列的最大功率点,不仅具有较快的跟踪速度,且跟踪精度达到99.1%。

光伏组件热斑效应研究

该文对目前主流的p型光伏组件产品特别是大尺寸太阳电池所制备光伏组件的热斑温度进行测试研究,具体分析影响热斑温度的关键影响因素,被遮挡太阳电池的热斑温度由单位面积上耗散的功率Φq决定,即与单串太阳电池片数量、太阳电池片漏电流、太阳电池片漏电流的分布相关,太阳电池片漏电点处的非均匀加热是热斑局部温度偏高的主要原因。同时对单串太阳电池片数相对较多的光伏组件热斑风险控制进行探讨,反偏电压下太阳电池漏电流值的控制能有效降低热斑温度,通过红外测试对一定反偏电压下太阳电池漏电点与非漏电区域太阳电池片温差分档,可进一步控制热斑风险。

Inkjet-Printed Organic Solar Cells and Perovskite Solar Cells: Progress,Challenges, and Prospect

In recent years,the power conversion efficiency of organic solar cells(OSCs)and perovskite(PVSCs)has increased to over 19%and25%,respectively.Meanwhile,the long-term stability of OSCs and PVSCs was also significantly improved with a better understanding of the degradation mechanism and the improvement of materials,morphology,and interface stability.As both the efficiency and lifetime of solar cells are approaching the commercialization limit,fabrication methods for large-area OSCs and PVSCs that can be directly transferred from lab to fab become essential to promote the industrialization of OSCs and PVSCs.Compared with the coating methods,inkjet printing is a mature industrial technology with the advantages of random digital patterning,excellent precision and fast printing speed,which is considered to have great potential in solar cell fabrication.Many efforts have been devoted to developing inkjet-printed OSCs and PVSCs,and much progress has been achieved in the last few years.In this review,we first introduced the working principle of inkjet printing,the rheology requirements of inks,and the behaviors of the droplets.We then summarized the recent research progresses of the inkjet-printed OSCs and PVSCs to facilitate knowledge transfer between the two technologies.In the end,we gave a perspective on inkjet-printed OSCs and PVSCs.

生物质基炭材料在染料敏化太阳能电池电极领域的研究进展

太阳能电池可将太阳能转化为电能,具有环保、高效等特性,因此受到国内外研究者的广泛关注。染料敏化太阳能电池(DSSCs)是一种备受瞩目的新型太阳能电池,但其所用的炭材料(如石墨烯、碳纳米管等)价格普遍较为昂贵,因此亟须开发高性能且价格低廉的炭材料。本综述旨在阐明生物质基炭材料在DSSCs中的应用策略和发展方向,为更好地促进生物质基炭材料在太阳能电池领域的应用提供科技支撑。生物质基炭材料具有电催化活性高、孔隙可调等特性,且来源广泛、制备简单、稳定性高。为了进一步增加比表面积,可以通过活化制备具有更多孔隙结构的活性炭材料;除了提供有序的分级孔隙结构,大多数生物质原料具有丰富的杂原子,因此杂原子掺杂可以在炭化后直接实现,从而提高生物质基炭材料的导电性;将生物质基炭材料与其他材料复合还可以进一步提高离子/电子迁移效率。这些生物质基炭材料应用在太阳能电池中可以有效地改善器件的稳定性、光电转换效率(PCE)等性能。笔者概述了生物质的来源和结构特性,归纳了生物质基炭材料的制备和修饰方法,并对DSSCs的工作原理进行了介绍,最后系统阐述了生物质基炭材料作为对电极、光阳极等DSSCs核心部件的研究进展和应用现状。

Polythiophene solar cells processed from non-halogenated solvent with 15.68%efficiency

Polythiophenes(PTs)are prospective polymer donors for large-scale manufacturing and industrialization owing to their simple structures and low synthetic cost.However,the fabrication of PT solar cells depends on highly toxic chlorinated solvents,and less research has been done on the use of more environmentally friendly non-halogenated solvents.Herein,highly efficient PT solar cells based on top-performance polythiophene,P5TCN-F25,processed from a non-halogenated solvent are reported by delicate aggregation control.A power conversion efficiency of up to 15.68%was achieved by depositing the active layer from a hot o-xylene solution,which is the record efficiency of non-halogenated processed PT solar cells up to date.The appropriate solution temperature is beneficial to the formation of ordered polymer stacking and desirable phase separation size,which thereby contributes to enhanced charge transfer efficiency,more balanced hole/electron mobility,and reduced trap-assisted recombination.These results provide valuable implications for improving the efficiency of PT solar cells via environmentallyfriendly processing.

Slot-die coated large-area flexible all-polymer solar cells by nonhalogenated solvent

The slot-die coating is recognized as the most compatible method for the roll-to-roll(R2R)processing of large-area flexible organic solar cells(OSCs).However,the photovoltaic performance of the large-area flexible all-polymer solar cells was significantly lagging behind that of polymer donors with small molecule non-fullerene acceptors devices.In this work,the 1 cm^(2) flexible device of an all-polymer system,PTQ10:PYF-T-o,fabricated by slot-die coating,achieves an excellent efficiency of 11.24%via controlling the coating temperatures.It is found that,compared with the donor,the crystallinity of PYF-T-o plays a crucial role in device performance.The all-polymer flexible devices show superior mechanical bending stability,maintaining an efficiency of over 95%of the initial value during a 1000-cycle bending test.

Graphdiyne oxide doping for aggregation control of hole-transportnanolayer in inverted perovskite solar cells

The strong aggregation tendency of hole transport material poly[3-(4-carboxylbutyl)thiophene-K(P3CT-K)restricts its further application in inverted perovskite solar cells(PSCs).Here,we report an effective strategy to address this issue and achieve the superior performance of inverted methylammonium lead triiodide(MAPbI3)PSCs,in which graphdiyne oxide(GDYO)doped P3CT-K nanocomposites are applied as the hole transport nanolayer(HTL).It is revealed that the strongπ–πstacking interaction occurs between GDYO and P3CT-K,which is proved by the blue shift of the absorption peak of P3CT-K nanolayer.The aggregation control via GDYO contributes to the property improvement of P3CT-K HTL.Moreover,the homogeneous coverage induces the growth of perovskite grain with larger size than that based on the undoped one.As a result,the optimized surface morphology,enhanced conductivity,charge extraction as well as better crystal quality,finally improve the device performance.An optimal power conversion efficiency of 19.06%is achieved,with simultaneously improved fill factor and short circuit current density.This work presents the potential of functional graphdiyne(GDY)in the development of highly efficient photovoltaic device.

Screen printing process control for coating high throughput titanium dioxide films toward printable mesoscopic perovskite solar cells

Screen printing technique has been widely applied for the manufacturing of both traditional silicon solar cells and emerging photovoltaics such as dyesensitized solar cells(DSSCs)and perovskite solar cells(PSCs).Particularly,we have developed a printable mesoscopic PSC based on a triple layer scaffold of TiO2/ZrO2/carbon.The deposition of the scaftold is entirely based on screen printing process,which provides a promising prospect for low-cost photovoltaics.However,the optimal thickness of the TiO2 layer for fabricating efficient printable PSCs is much smaller than the typical thickness of screen printed films.Here,we tune the concentration of the pastes and the printing parameters for coating TiO?films,and successfully print TiO2 films with the thickness of 500-550 nm.The correlation between the thickness of the films and printing parameters such as the solid content and viscosity of the pastes,the printing speed and pressure,and the temperature has been investigated.Besides,the edge effect that the edge of the TiO2 films possesses a much larger thickness and printing positional accuracy have been studied.This work will significantly benefit the further development of printable mesoscopic PSCs.

一种低温退火处理提高锡基钙钛矿太阳能电池效率的方法

钙钛矿光伏材料是目前最具发展前景的一类光伏材料,其铅基光伏器件的小面积认证效率已突破25%。然而,铅元素严重的毒性问题成为钙钛矿光伏实用化的重要阻碍之一。锡基钙钛矿材料因其低毒性和理想的光电性能被认为是最有可能替代铅基钙钛矿的候选材料。然而,锡基钙钛矿过快的晶体生长速率往往造成制备的薄膜质量欠佳,限制了锡基钙钛矿太阳能电池(TPSC)光电转换效率的提高。本研究在锡基钙钛矿薄膜的制备流程中引入了一种低温退火处理,即在钙钛矿薄膜旋涂结束后先进行低温退火再进行常规的90℃退火。该处理可在不改变钙钛矿晶型且不引入新的组分的前提下减缓钙钛矿薄膜结晶过程中的晶体生长,从而减少锡基钙钛矿薄膜表面的孔洞缺陷,提高薄膜的光捕获能力,降低器件内载流子复合。最优器件效率由3.65%提高到了5.38%,填充因子提高了29.84%。

不同溶剂诱导的中间相对钙钛矿薄膜结晶的影响

有机-无机杂化钙钛矿(MAPbI_(3))太阳能电池的光电转化效率增长飞速而被广泛关注。然而由于PbI_(2)的生长速率要快于MAI的生长速率,导致钙钛矿晶体的形貌难以控制。因此,制备MAPbI_(3)过程中统一MAI和PbI_(2)生长速率极为重要。二甲基甲酰胺(DMF)和二甲基亚砜(DMSO)作为氧给体可与PbI_(2)形成配合物,用来制备致密的钙钛矿薄膜。通过改变前驱体溶液中DMF和DMSO的比例,调控中间相的形成过程实现了对晶体生长速率的调控。此外,DMSO与PbI_(2)的配位能力要强于DMF,并且DMSO更容易与路易斯酸PbI_(2)的S=O双键发生作用,影响晶体的生长速率。最后,基于最佳浓度的DMSO前驱体溶液制备的钙钛矿薄膜的光伏器件,其光电转化效率可以达到16.41%。