共查询到20条相似文献,搜索用时 15 毫秒
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Huanhuan Wang Zaiwei Wang Zhen Yang Yuzeng Xu Yi Ding Liguo Tan Chenyi Yi Zhuang Zhang Ke Meng Gang Chen Ying Zhao Yongsong Luo Xiaodan Zhang Anders Hagfeldt Jingshan Luo 《Advanced materials (Deerfield Beach, Fla.)》2020,32(21):2000865
Excess lead iodide (PbI2), as a defect passivation material in perovskite films, contributes to the longer carrier lifetime and reduced halide vacancies for high-efficiency perovskite solar cells. However, the random distribution of excess PbI2 also leads to accelerated degradation of the perovskite layer. Inspired by nanocrystal synthesis, here, a universal ligand-modulation technology is developed to modulate the shape and distribution of excess PbI2 in perovskite films. By adding certain ligands, perovskite films with vertically distributed PbI2 nanosheets between the grain boundaries are successfully achieved, which reduces the nonradiative recombination and trap density of the perovskite layer. Thus, the power conversion efficiency of the modulated device increases from 20% to 22% compared to the control device. In addition, benefiting from the vertical distribution of excess PbI2 and the hydrophobic nature of the surface ligands, the modulated devices exhibit much longer stability, retaining 72% of their initial efficiency after 360 h constant illumination under maximum power point tracking measurement. 相似文献
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Ganbaatar Tumen-Ulzii Chuanjiang Qin Dino Klotz Matthew R. Leyden Pangpang Wang Morgan Auffray Takashi Fujihara Toshinori Matsushima Jin-Wook Lee Sung-Joon Lee Yang Yang Chihaya Adachi 《Advanced materials (Deerfield Beach, Fla.)》2020,32(16):1905035
Excess/unreacted lead iodide (PbI2) has been commonly used in perovskite films for the state-of-the-art solar cell applications. However, an understanding of intrinsic degradation mechanisms of perovskite solar cells (PSCs) containing unreacted PbI2 has been still insufficient and, therefore, needs to be clarified for better operational durability. Here, it is shown that degradation of PSCs is hastened by unreacted PbI2 crystals under continuous light illumination. Unreacted PbI2 undergoes photodecomposition under illumination, resulting in the formation of lead and iodine in films. Thus, this photodecomposition of PbI2 is one of the main reasons for accelerated device degradation. Therefore, this work reveals that carefully controlling the formation of unreacted PbI2 crystals in perovskite films is very important to improve device operational stability for diverse opto-electronic applications in the future. 相似文献
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Stability of Halide Perovskite Solar Cell Devices: In Situ Observation of Oxygen Diffusion under Biasing 下载免费PDF全文
Hee Joon Jung Daehan Kim Sungkyu Kim Joonsuk Park Vinayak P. Dravid Byungha Shin 《Advanced materials (Deerfield Beach, Fla.)》2018,30(39)
Using in situ electrical biasing transmission electron microscopy, structural and chemical modification to n–i–p‐type MAPbI3 solar cells are examined with a TiO2 electron‐transporting layer caused by bias in the absence of other stimuli known to affect the physical integrity of MAPbI3 such as moisture, oxygen, light, and thermal stress. Electron energy loss spectroscopy (EELS) measurements reveal that oxygen ions are released from the TiO2 and migrate into the MAPbI3 under a forward bias. The injection of oxygen is accompanied by significant structural transformation; a single‐crystalline MAPbI3 grain becomes amorphous with the appearance of PbI2. Withdrawal of oxygen back to the TiO2, and some restoration of the crystallinity of the MAPbI3, is observed after the storage in dark under no bias. A subsequent application of a reverse bias further removes more oxygen ions from the MAPbI3. Light current–voltage measurements of perovskite solar cells exhibit poorer performance after elongated forward biasing; recovery of the performance, though not complete, is achieved by subsequently applying a negative bias. The results indicate negative impacts on the device performance caused by the oxygen migration to the MAPbI3 under a forward bias. This study identifies a new degradation mechanism intrinsic to n–i–p MAPbI3 devices with TiO2. 相似文献
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Enhancing the Performance of Perovskite Solar Cells by Hybridizing SnS Quantum Dots with CH3NH3PbI3 下载免费PDF全文
Jianhua Han Xuewen Yin Hui Nan Yu Zhou Zhibo Yao Jianbao Li Dan Oron Hong Lin 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(32)
The combination of perovskite solar cells and quantum dot solar cells has significant potential due to the complementary nature of the two constituent materials. In this study, solar cells (SCs) with a hybrid CH3NH3PbI3/SnS quantum dots (QDs) absorber layer are fabricated by a facile and universal in situ crystallization method, enabling easy embedding of the QDs in perovskite layer. Compared with SCs based on CH3NH3PbI3, SCs using CH3NH3PbI3/SnS QDs hybrid films as absorber achieves a 25% enhancement in efficiency, giving rise to an efficiency of 16.8%. The performance improvement can be attributed to the improved crystallinity of the absorber, enhanced photo‐induced carriers' separation and transport within the absorber layer, and improved incident light utilization. The generality of the methods used in this work paves a universal pathway for preparing other perovskite/QDs hybrid materials and the synthesis of entire nontoxic perovskite/QDs hybrid structure. 相似文献
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The recently emerged integrated perovskite/bulk-heterojunction (BHJ) organic solar cells (IPOSCs) without any recombination layers have generated wide attention. This type of device structure can take the advantages of tandem cells using both perovskite solar and near-infrared (NIR) BHJ organic solar materials for wide-range sunlight absorption and the simple fabrication of single junction cells, as the low bandgap BHJ layer can provide additional light harvesting in the NIR region and the high open-circuit voltage can be maintained at the same time. This progress report highlights the recent developments in such IPOSCs and the possible challenges ahead. In addition, the recent development of perovskite solar cells and NIR organic solar cells is also covered to fully underline the importance and potential of IPOSCs. 相似文献
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Pankaj Yadav M. Ibrahim Dar Neha Arora Essa A. Alharbi Fabrizio Giordano Shaik Mohammed Zakeeruddin Michael Grätzel 《Advanced materials (Deerfield Beach, Fla.)》2017,29(40)
Perovskite solar cells (PSCs) based on cesium (Cs)‐ and rubidium (Rb)‐containing perovskite films show highly reproducible performance; however, a fundamental understanding of these systems is still emerging. Herein, this study has systematically investigated the role of Cs and Rb cations in complete devices by examining the transport and recombination processes using current–voltage characteristics and impedance spectroscopy in the dark. As the credibility of these measurements depends on the performance of devices, this study has chosen two different PSCs, (MAFACs)Pb(IBr)3 (MA = CH3NH3+, FA = CH(NH2)2+) and (MAFACsRb)Pb(IBr)3, yielding impressive performances of 19.5% and 21.1%, respectively. From detailed studies, this study surmises that the confluence of the low trap‐assisted charge‐carrier recombination, low resistance offered to holes at the perovskite/2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenylamine)‐9,9‐spirobifluorene interface with a low series resistance (Rs), and low capacitance leads to the realization of higher performance when an extra Rb cation is incorporated into the absorber films. This study provides a thorough understanding of the impact of inorganic cations on the properties and performance of highly efficient devices, and also highlights new strategies to fabricate efficient multiple‐cation‐based PSCs. 相似文献
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Bo Li Huayan Wang Aqiang Liu Yang Liu Wei Pu Ting Shen Mengjie Li Meidan Que Jianjun Tian Qilin Dai Sining Yun 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(35):2301061
The additive engineering strategy promotes the efficiency of solution-processed perovskite solar cells (PSCs) over 25%. However, compositional heterogeneity and structural disorders occur in perovskite films with the addition of specific additives, making it imperative to understand the detrimental impact of additives on film quality and device performance. In this work, the double-edged sword effects of the methylammonium chloride (MACl) additive on the properties of methylammonium lead mixed-halide perovskite (MAPbI3-xClx ) films and PSCs are demonstrated. MAPbI3-xClx films suffer from undesirable morphology transition during annealing, and its impacts on the film quality including morphology, optical properties, structure, and defect evolution are systematically investigated, as well as the power conversion efficiency (PCE) evolution for related PSCs. The FAX (FA = formamidinium, X = I, Br, and Ac) post-treatment strategy is developed to inhibit the morphology transition and suppress defects by compensating for the loss of the organic components, a champion PCE of 21.49% with an impressive open-circuit voltage of 1.17 V is obtained, and remains over 95% of the initial efficiency after storing over 1200 hours. This study elucidates that understanding the additive-induced detrimental effects in halide perovskites is critical to achieve the efficient and stable PSCs. 相似文献
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The highest power conversion efficiency of perovskite solar cells is beyond 22%. Charge transport layers are found to be critical for device performance and stability. A traditional electron transport layer (ETL), such as TiO2, is not very efficient for charge extraction at the interface, especially in planar structure. In addition, the devices using TiO2 suffer from serious degradation under ultraviolet illumination. SnO2 owns a better band alignment with the perovskite absorption layer and high electron mobility, which is helpful for electron extraction. In this Review, recent progresses in efficient and stable perovskite solar cells using SnO2 as ETL are summarized. 相似文献
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Zhipeng Shao Hongguang Meng Xiaofan Du Xiuhong Sun Peiliang Lv Caiyun Gao Yi Rao Chen Chen Zhipeng Li Xiao Wang Guanglei Cui Shuping Pang 《Advanced materials (Deerfield Beach, Fla.)》2020,32(30):2001054
The stability issue is still one of the main limitations of the commercialization of perovskite photovoltaics. The mixed cation FAxCs1−xPbI3 has shown great promise owing to its improved thermal and moisture stability. However, the study of FAxCs1−xPbI3 is concentrated on formamidine (FA)-rich perovskite, whereas cesium (Cs)-rich FAxCs1−xPbI3 perovskites are barely studied due to the inevitable phase separation when Cs > 30 mol%. Here, a Cs4PbI6-mediated method is developed to synthesize Cs-rich FAxCs1−xPbI3 perovskites. It is demonstrated that Cs4PbI6 intermediate phase has a low Cs cation diffusion barrier and therefore offers a fast ion exchange with the preformed FA-rich perovskite phase to finally form the Cs-rich FAxCs1−xPbI3 perovskite. The results indicate that ≈15% alloying with organic FA cations can sufficiently stabilize the perovskite phase with excellent phase and UV-irradiation stability. The FA0.15Cs0.85PbI3 perovskite solar cells achieve a champion power conversion efficiency of 17.5%, showing the great potential of Cs-based perovskites for efficient and stable solar cells. 相似文献
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Furui Tan Hairen Tan Makhsud I. Saidaminov Mingyang Wei Mengxia Liu Anyi Mei Peicheng Li Bowen Zhang Chih‐Shan Tan Xiwen Gong Yongbiao Zhao Ahmad R. Kirmani Ziru Huang James Z. Fan Rafael Quintero‐Bermudez Junghwan Kim Yicheng Zhao Oleksandr Voznyy Yueyue Gao Feng Zhang Lee J. Richter Zheng‐Hong Lu Weifeng Zhang Edward H. Sargent 《Advanced materials (Deerfield Beach, Fla.)》2019,31(14)
Organic–inorganic hybrid perovskite solar cells (PSCs) have seen a rapid rise in power conversion efficiencies in recent years; however, they still suffer from interfacial recombination and charge extraction losses at interfaces between the perovskite absorber and the charge–transport layers. Here, in situ back‐contact passivation (BCP) that reduces interfacial and extraction losses between the perovskite absorber and the hole transport layer (HTL) is reported. A thin layer of nondoped semiconducting polymer at the perovskite/HTL interface is introduced and it is shown that the use of the semiconductor polymer permits—in contrast with previously studied insulator‐based passivants—the use of a relatively thick passivating layer. It is shown that a flat‐band alignment between the perovskite and polymer passivation layers achieves a high photovoltage and fill factor: the resultant BCP enables a photovoltage of 1.15 V and a fill factor of 83% in 1.53 eV bandgap PSCs, leading to an efficiency of 21.6% in planar solar cells. 相似文献
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Shanshan Zhang Seyed M. Hosseini Ren Gunder Andrei Petsiuk Pietro Caprioglio Christian M. Wolff Safa Shoaee Paul Meredith Susan Schorr Thomas Unold Paul L. Burn Dieter Neher Martin Stolterfoht 《Advanced materials (Deerfield Beach, Fla.)》2019,31(30)
2D Ruddlesden–Popper perovskite (RPP) solar cells have excellent environmental stability. However, the power conversion efficiency (PCE) of RPP cells remains inferior to 3D perovskite‐based cells. Herein, 2D (CH3(CH2)3NH3)2(CH3NH3)n?1PbnI3n+1 perovskite cells with different numbers of [PbI6]4? sheets (n = 2–4) are analyzed. Photoluminescence quantum yield (PLQY) measurements show that nonradiative open‐circuit voltage (VOC) losses outweigh radiative losses in materials with n > 2. The n = 3 and n = 4 films exhibit a higher PLQY than the standard 3D methylammonium lead iodide perovskite although this is accompanied by increased interfacial recombination at the top perovskite/C60 interface. This tradeoff results in a similar PLQY in all devices, including the n = 2 system where the perovskite bulk dominates the recombination properties of the cell. In most cases the quasi‐Fermi level splitting matches the device VOC within 20 meV, which indicates minimal recombination losses at the metal contacts. The results show that poor charge transport rather than exciton dissociation is the primary reason for the reduction in fill factor of the RPP devices. Optimized n = 4 RPP solar cells had PCEs of 13% with significant potential for further improvements. 相似文献
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Jiangjian Shi Xin Xu Dongmei Li Qingbo Meng 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(21):2472-2486
The interfacial atomic and electronic structures, charge transfer processes, and interface engineering in perovskite solar cells are discussed in this review. An effective heterojunction is found to exist at the window/perovskite absorber interface, contributing to the relatively fast extraction of free electrons. Moreover, the high photovoltage in this cell can be attributed to slow interfacial charge recombination due to the outstanding material and interfacial electronic properties. However, some fundamental questions including the interfacial atomic and electronic structures and the interface stability need to be further clarified. Designing and engineering the interfaces are also important for the next‐stage development of this cell. 相似文献
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Efficient Perovskite Solar Cells Fabricated Through CsCl‐Enhanced PbI2 Precursor via Sequential Deposition 下载免费PDF全文
Qi Li Yicheng Zhao Rui Fu Wenke Zhou Yao Zhao Xin Liu Dapeng Yu Qing Zhao 《Advanced materials (Deerfield Beach, Fla.)》2018,30(40)
The fabrication of high‐quality perovskite film highly relies on chemical composition and the synthesis method of perovskite. So far, sequentially deposited MA0.03FA0.97Pb(I0.97Br0.03)3 polycrystalline film is adopted to produce high‐performance perovskite solar cells with record power conversion efficiency (PCE). Fewer grain boundaries and incorporation of inorganic cation (e.g., cesium) would further increase device performance via sequential deposition. Here, cesium chloride (CsCl) is introduced into lead iodide (PbI2) precursor solution that beneficially modulates the property of PbI2 film, leading to larger grains with cesium incorporation in the resulting perovskite film. The enlarged crystal grains originate from a slower nucleation process for CsCl‐containing PbI2 film when reacting with formamidine iodide, confirmed by in situ confocal photoluminescence imaging. Photovoltaic devices based on CsCl‐containing PbI2 film demonstrate a higher averaging efficiency of 21.3% than 20.3% of the devices without CsCl additives for reverse scan. More importantly, the device stability is improved by CsCl additives that retain over 90% of their initial PCE value after 4000 min tracking at maximum power point under 1‐sun illumination. This work paves a way to further improve the photovoltaic performance of mixed‐cation‐halide perovskite solar cells via a sequential deposition method. 相似文献