锡钙钛矿太阳能电池的进展与展望

金属卤素钙钛矿是目前最有前景的高效低成本新型太阳能电池材料,但是目前还存在环境友好性和理论效率极限较低的问题。锡钙钛矿环境友好,而且其带隙更窄理论转换效率更高,吸引了广泛的关注。锡钙钛矿太阳能电池(TPSC)近年来发展迅速,是目前效率最高的无铅钙钛矿太阳能电池。本文先介绍了锡钙钛矿的晶体结构、能带结构和光电性质,然后总结了最近在锡钙钛矿领域有代表性的工作和提高光电转化效率的策略,最后讨论了锡钙钛矿发展面临的挑战和未来的发展方向。     

多维CsPbX3无机钙钛矿材料的制备及其在太阳能电池中的应用

近年来全无机CsPbX₃(X=Cl、Br、I)型钙钛矿材料由于其高吸光系数、低激子束缚能、长的载流子扩散长度等优点使其在太阳能电池(PSC)器件应用方面备受关注。高效的合成方法和精准的形貌控制对无机钙钛矿的光学性质及其太阳能电池光电性能及稳定性至关重要。本文系统介绍了不同维度无机钙钛矿材料包括零维量子点、一维纳米线/棒、二维纳米片和三维纳米花的现有合成方法;比较了各种合成方法的优势;着重介绍了不同维度无机钙钛矿材料的形貌调控手段,光学性质及相应太阳能电池光电性能的优化策略;最后展望了全无机钙钛矿朝着无害化和高性能钙钛矿太阳能电池的应用前景。     

高效率钙钛矿型太阳能电池的化学稳定性及其研究进展

近几年来, 钙钛矿太阳能电池器件光电转换效率的最高纪录不断被刷新, 但是关于钙钛矿太阳能电池稳定性的研究报道比较缺乏. 钙钛矿太阳能电池稳定性问题已经成为制约钙钛矿太阳能电池继续发展的瓶颈. 简要讨论了水氧气氛、温度变化、湿法制备、紫外光照等不同敏感环境条件下钙钛矿太阳能电池的化学稳定性问题, 进而对一定环境条件下钙钛矿太阳能电池的化学稳定性及其调控的研究现状进行了综述, 旨在更好地理解钙钛矿太阳能电池稳定性的基础理论问题, 为实现钙钛矿太阳能电池稳定性的调控提供基本依据.     

金属卤化物钙钛矿光电材料和器件

2009年ABX₃钙钛矿晶型的甲胺铅卤CH₃NH₃PbX₃(X=I、Br、Cl)钙钛矿材料首次应用于太阳能电池,但初始报道效率低、稳定性差。2012年后,可溶液法制备的钙钛矿太阳能电池凭借其吸光系数高、激子结合能低等优点,迅速表现出低成本和高效率的突出优势,并在光电器件等交叉领域具有很强的应用潜力。因此,钙钛矿太阳能电池被Science杂志评为2013年度国际十大科技进展,是化学和材料领域特别是光伏领域新兴的变革性技术之一。钙钛矿太阳能电池材料与器件的发展一直面临大面积、高效率、稳定性和环境友好性等挑战,对应的是钙钛矿晶体可控生长、缺陷钝化、器件优化材料稳定性和铅毒性等科学问题。     

钙钛矿型太阳能电池制备工艺及稳定性研究进展

有机-无机杂化钙钛矿型太阳能电池因其简单的制备工艺,低廉的制造成本,优异的光电转换效率,成为光伏领域的研究热点。钙钛矿光吸收材料具有消光系数高、载流子迁移率高、载流子寿命长、带隙可调控等优点。短短几年内,钙钛矿型太阳能电池的效率从最初的3.8%提高到22.1%。目前,为了获得稳定高效的钙钛矿型太阳能电池,主要有以下几个研究思路：新型器件结构设计;结构功能层的材料形貌设计;结构各功能层间的界面修饰;空穴传输材料的选择;对电极的选择。本文通过文献综述,在回顾了国内外研究者对钙钛矿型太阳能电池的研究历程的基础上,介绍了钙钛矿型太阳能电池的结构和工作原理,重点总结了电子传输层和钙钛矿层的制备工艺及优化,并讨论了钙钛矿型太阳能电池的稳定性以及展望了其商业化的前景。     

钙钛矿型太阳能电池制备工艺及稳定性研究进展

有机-无机杂化钙钛矿型太阳能电池因其简单的制备工艺,低廉的制造成本,优异的光电转换效率,成为光伏领域的研究热点。钙钛矿光吸收材料具有消光系数高、载流子迁移率高、载流子寿命长、带隙可调控等优点。短短几年内,钙钛矿型太阳能电池的效率从最初的3.8%提高到22.1%。目前,为了获得稳定高效的钙钛矿型太阳能电池,主要有以下几个研究思路:新型器件结构设计;结构功能层的材料形貌设计;结构各功能层间的界面修饰;空穴传输材料的选择;对电极的选择。本文通过文献综述,在回顾了国内外研究者对钙钛矿型太阳能电池的研究历程的基础上,介绍了钙钛矿型太阳能电池的结构和工作原理,重点总结了电子传输层和钙钛矿层的制备工艺及优化,并讨论了钙钛矿型太阳能电池的稳定性以及展望了其商业化的前景。     

二维钙钛矿光伏器件

有机-无机杂化卤化物钙钛矿太阳能电池(perovskite solar cells, PSCs)由于其成本低廉、制备工艺简单、光电转换率高等优点引起了越来越多的关注,在下一代半导体光伏技术中显示出巨大的发展潜力。然而PSCs器件在商业化生产应用之前,必须解决某些关键问题,例如器件在湿度、光照和过热条件下缺乏稳定性,性能会急剧衰退。层状二维(two-dimensional, 2D)钙钛矿由于其优异的环境稳定性而受到研究人员的广泛关注。通过引入不同种类的疏水性大体积有机铵阳离子可以在钙钛矿体内形成稳定的2D结构。然而,由于绝缘有机间隔阳离子的存在,使其电荷输运能力受阻并影响光电转换性能。本文根据不同种类2D钙钛矿光伏器件的发展进程,总结了影响2D钙钛矿结构和性能的关键问题,如晶体垂直取向设计、量子阱调控和有机层间隔阳离子替换工程等。最后对2D PSCs的未来发展进行展望。     

可溶液加工的有机-无机杂化钙钛矿:超越光伏应用的“梦幻”材料

有机-无机杂化钙钛矿材料是可通过溶液工艺低温制备得到的直接带隙半导体晶体薄膜.在众多可溶液加工的半导体材料中,有机-无机杂化钙钛矿薄膜是为数不多的低缺陷密度、双极子传输性能优异的晶体薄膜,同时兼具宽光谱吸收和长载流子扩散距离等特性,是平面异质结太阳能电池的理想选择.另外,作为低缺陷密度的直接带隙半导体晶体材料,杂化钙钛矿薄膜具有优异的发光特性.其发光波长可通过能带工程(在分子水平上改变其组分)进行调节,因此有望在发光二极管和激光等光电器件中得到新应用.总结了钙钛矿材料的优异特性和目前应用研究的进展,并对其未来发展做了展望.     

无机卤化物钙钛矿纳米结构的带隙可调制备及光电应用研究

在半导体领域,通过合金化集成两种以上半导体的单纳米结构近年来相继问世,随着纳米材料的成分变化,可以灵活实现半导体的带隙调控,在光通信以及集成光电器件领域有着广泛的应用。然而,传统半导体纳米结构因不同成分之间存在晶格失配,其带隙调节的范围受到了很大限制。因此,钙钛矿作为对晶格失配具有高容忍度的半导体材料,在半导体带隙调控及器件研究领域显示出了巨大的潜力。本文综述了无机卤化物钙钛矿一维合金纳米材料的合成方法以及近年来的研究进展,总结了可调带隙钙钛矿一维合金纳米材料在光电子器件领域中的应用,包括波长可调谐纳米激光器、光电探测器、白光发光二极管、全光开关、太阳能电池等。实现单纳米结构带隙工程将对未来集成器件的发展产生深远的影响。     

无机钙钛矿太阳能电池稳定性研究进展

近年来钙钛矿太阳能电池发展迅速,全无机钙钛矿具有良好的热稳定性、高吸光系数、带隙可调、制备简单等优点备受关注.现今,无机钙钛矿太阳能电池的最高光电转化效率已达19.03%,具有很好的发展潜力.本综述将从无机钙钛矿太阳能电池的制备方法、薄膜掺杂、界面修饰对稳定性影响入手,系统介绍无机钙钛矿太阳能电池的发展并进行分析总结,并着重分析了无机钙钛矿不稳定的原因及其改善方法,最后对于无机钙钛矿太阳能电池的未来进行了展望.     

Sn类钙钛矿太阳电池薄膜的掺杂改性研究

采用一步法分别制备了Sn类CH3NH3Sn I3和Pb类CH3NH3Pb I3钙钛矿太阳电池薄膜材料,并对其表面形貌、微观结构、吸收光谱和电池器件性能进行了表征和测试。研究结果表明:Sn类钙钛矿材料的吸收光谱相对于Pb类钙钛矿材料发生了明显的红移,吸收截止波长从800 nm上升到950 nm左右,光学带隙由1.45 e V降低至1.21 e V左右;Sn类钙钛矿材料的光谱吸收范围明显扩大,但吸收强度有所降低,相应太阳电池器件的光电转换效率也明显低于Pb类钙钛矿太阳电池,分别为2.05%和6.71%。而Br的掺杂可使Sn类钙钛矿材料带隙变宽,吸收光子能量增大,电池器件的开路电压也相应提高。当Br含量由0增加至完全替代I时,Sn类钙钛矿材料逐渐由黑褐色转变为黄色,光学带隙增大至1.95 e V,但吸收截止波长由950 nm降低至650nm。值得提及的是当Br含量为0.5时,电池器件的光电转换效率可由最初的2.05%提升至2.94%。     

Determination of The Oxygen Chemical Diffusion Coefficient in Perovskites by a Thermogravimetric Method

A thermogravimetric method has been used for the determination of the oxygen chemical diffusion coefficients in La_1–xSr_xMnO_3+δ; x=0; 0.05; 0.10; 0.15 (LSM). A temperature range of 700–1000°C was studied. The chemical diffusion coefficient varies between 1.6⋅10^–13 and 1.8⋅10^–10cm²s^–1 for the samples in the temperature range studied. The activation energy for oxygen chemical diffusion was determined to be 190–280 kJ mol^–1 for the LSM samples. The magnitude of the chemical diffusion coefficients of the LSM samples does not depend on the strontium site occupation factor. This revised version was published online in July 2006 with corrections to the Cover Date.     

钛基钙钛矿型光催化材料的研究进展

由于化石能源的快速消耗以及化石能源在燃烧过程中会释放有害气体,所以寻找新的、干净的能源体系迫在眉睫。氢能具有高燃烧值和高效率的优点,成为了目前最有前景的新能源之一,而利用太阳能进行光催化产氢是最符合"绿色化学"的方法之一。根据目前所探究的光催化剂,钙钛矿型光催化剂因其多样性、特征性以及可变性成为了热门的研究体系。钛基钙钛矿材料及其衍生物表现出了许多优异的光催化活性,是太阳能光催化研究领域的研究热点。本文详细综述了钛基钙钛矿材料及其衍生物的结构、改性方式以及在光催化分解水领域的研究进展。     

Syntheses and characterizations of complex perovskite oxynitrides LaMg1/3Ta2/3O2N, LaMg1/2Ta1/2O5/2N1/2, and BaSc0.05Ta0.95O2.1N0.9

The following complex oxynitride perovskites have been prepared: LaMg_1/3Ta_2/3O₂N, LaMg_1/2Ta_1/2O_5/2N_1/2, and BaSc_0.05Ta_0.95O_2.1N_0.9. Synchrotron X-ray powder diffraction analyses show that LaMg_1/3Ta_2/3O₂N and LaMg_1/2Ta_1/2O_5/2N_1/2 are isostructural to the oxide La₂Mg(Mg_1/3Ta_2/3)O₆ (space group P2₁/n), whereas BaSc_0.05Ta_0.95O_2.1N_0.9 has a simple cubic symmetry similarly to BaTaO₂N. The orderings of octahedral cations are markedly diminished in the above oxynitrides, as compared with the related oxides such as La₂Mg(Mg_1/3Ta_2/3)O₆ and Ba₂ScTaO₆. The optical band gaps are similar for the homologous compositions, LaMg_1/3Ta_2/3O₂N, LaMg_1/2Ta_1/2O_5/2N_1/2 and LaTaON₂ (1.9 eV), and BaSc_0.05Ta_0.95O_2.1N_0.9 and BaTaO₂N (1.8 eV), while the absorption edges become broader for the complex derivatives. As revealed from the impedance spectroscopic analysis, the oxynitrides have clearly different dielectric components from those of comparable oxides containing Ta⁵⁺. Impedance spectroscopy reveals interesting capacitor geometry in BaSc_0.05Ta_0.95O_2.1N_0.9 in which the semiconducting oxynitride grains are separated by insulating secondary phases. Most notably BaSc_0.05Ta_0.95O_2.1N_0.9 has a bulk component with a high relative permittivity (κ=7300) and the grain boundary component with an even higher κ.     

Recent Advances and Future Perspectives of Lead-Free Halide Perovskites for Photocatalytic CO2 Reduction

It is still challenging to design and develop the state-of-the-art photocatalysts toward CO₂ photoreduction. Enormous researchers have focused on the halide perovskites in the photocatalytic field for CO₂ photoreduction, due to their excellent optical and physical properties. The toxicity of lead-based halide perovskites prevents their large-scale applications in photocatalytic fields. In consequence, lead-free halide perovskites (LFHPs) without the toxicity become the promising alternatives in the photocatalytic application for CO₂ photoreduction. In recent years, the rapid advances of LFHPs have offer new chances for the photocatalytic CO₂ reduction of LFHPs. In this review, we summarize not only the structures and properties of A₂BX₆, A₂B(I)B(III)X₆, and A₃B₂X₉-type LFHPs but also their recent progresses on the photocatalytic CO₂ reduction. Furthermore, we also point out the opportunities and perspectives to research LFHPs photocatalysts for CO₂ photoreduction in the future.     

Optoelectronic and morphology properties of perovskite/silicon interface layer for tandem solar cell application

Silicon (Si) solar cell has low optical absorption because of the low and indirect bandgap of Si, and the efficiency was trapped at 25% for 15 years. Si solar cell is able to achieve efficiency up to 30% by adding perovskite as multiple bandgap material through tandem formation. In this paper, the Si/perovskite interface layer was characterized to study the compatibility of perovskite on fluorine-doped tin oxide (FTO) glass and p-type Si wafer (p-Si). The single solution deposition step of methyl ammonium lead iodide, CH₃NH₃PbI₃ (MAPbI₃) perovskite film, was spin-coated at different concentration. The physical properties of the MAPbI₃/FTO and MAPbI₃/p-Si were obtained by profilometer, atomic force microscope, X-ray diffraction, and Raman spectroscopy. The optical properties were analyzed by ultraviolet-visible spectroscopy, photoluminescence, and infrared transmission. Then the electrical properties were measured by Hall effect. From the measurement, it is observed that 1.2M concentration of MAPbI₃ thin film has the highest thickness, smoothest film surface, and largest crystallite size compared with 0.8M and 1.0M. It is found that there is an interaction in perovskite/Si interface and caused in a low-wavelength shift, and the increase in concentration of MAPbI₃ helped in intensifying the Raman signal produced. 1.2M MAPbI₃ thin film had the highest enhancement in light trapping property rather than 0.8M and 1.0M. The bulk concentration and conductivity of 1.2M perovskite were higher, but the resistivity was lower than 0.8M MAPbI₃ because of more CH₃NH₃I and PbI₂ concentration within MAPbI₃ perovskite compound.     

Band‐Edge Luminescence from Oxide and Halide Perovskite Semiconductors

Because perovskite crystals exhibit unique magnetic, conductive, and optical properties, they have been the subject of many fundamental investigations in various research fields. However, investigations related to their use as optoelectronic device materials are still in their early days. Regarding oxide perovskites, which have been investigated for a long time, the efficiency of photoluminescence (PL) induced by band‐to‐band transitions is extremely low because of the localized nature of the carriers in these materials. On the other hand, halide perovskites exhibit a highly efficient band‐edge PL attributable to the recombination of delocalized photocarriers. Therefore, it is expected that this class of high‐quality materials will be advantageous for optoelectronic devices such as solar cells and light‐emitting diodes. In this Minireview, we discuss various aspects of the PL properties and carrier dynamics of SrTiO₃ and CH₃NH₃PbX₃ (X=I, Br), which are representative oxide and halide perovskites.     

全无机钙钛矿太阳电池的制备及稳定性

全无机钙钛矿太阳电池因其热稳定性好、载流子迁移率高,可用于制备叠层电池等优点备受关注。随着人们对全无机钙钛矿太阳电池的深入研究和制备工艺的持续优化,全无机钙钛矿太阳电池的光电转换效率已经突破19%。然而,全无机钙钛矿材料相稳定性较差,这使得实现全无机钙钛矿太阳电池在空气环境下制备和长期使用面临巨大挑战。众多科研工作者通过分析全无机钙钛矿材料的相变机制,有针对性地提出了包括添加剂工程、界面工程和开发全无机钙钛矿量子点电池等多种方式来改善全无机钙钛矿太阳电池的长期稳定性。本综述从全无机钙钛矿材料与电池的结构、活性层制备方法和稳定性研究三个方面总结了近年来关于全无机钙钛矿太阳电池的研究进展。     

Lights and Shadows of DMSO as Solvent for Tin Halide Perovskites

In 2020 dimethyl sulfoxide (DMSO), the ever-present solvent for tin halide perovskites, was identified as an oxidant for Sn^II. Nonetheless, alternatives are lacking and few efforts have been devoted to replacing it. To understand this trend it is indispensable to learn the importance of DMSO on the development of tin halide perovskites. Its unique properties have allowed processing compact thin-films to be integrated into tin perovskite solar cells. Creative approaches for controlling the perovskite crystallization or increasing its stability to oxidation have been developed relying on DMSO-based inks. However, increasingly sophisticated strategies appear to lead the field to a plateau of power conversion efficiency in the range of 10–15 %. And, while DMSO-based formulations have performed in encouraging means so far, we should also start considering their potential limitations. In this concept article, we discuss the benefits and limitations of DMSO-based tin perovskite processing.     

Tailoring Component Interaction for Air-Processed Efficient and Stable All-Inorganic Perovskite Photovoltaic

All-inorganic lead halide perovskites are promising candidates for optoelectronic applications. However, fundamental questions remain over the component interaction in the perovskite precursor solution due to the limitation of the most commonly used solvents of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Here, we report an interaction tailoring strategy for all-inorganic CsPbI_3−xBr_x perovskites by involving the ionic liquid solvent methylammonium acetate (MAAc). C=O shows strong interaction with lead (Pb²⁺) and N−H⋅⋅⋅I hydrogen bond formation is observed. The interactions stabilize the perovskite precursor solution and allow production of the high-quality perovskite films by retarding the crystallization. Without the necessity for antisolvent treatment, the one-step air-processing approach delivers photovoltaic cells regardless of humidity, with a high efficiency of 17.10 % along with long operation stability over 1500 h under continuous light illumination.