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1.
An additive in hybrid perovskite is playing a vital role in the increment of power conversion efficiency (PCE), stability, and reproducibility of perovskite solar cells (PVSCs). Although, single-phase α-FAPbI3 perovskite has an ideal band gap but is continuously transforming to δ–FAPbI3, which is non-photoactive. Here, we controlled the methylammonium (MA) and formamidinium (FA) ratio in the (MAxFA1-x)PbI3 perovskite composition and tuned its morphology with the help of the thioacetamide (TAA) Lewis base additive. The optimum MA:FA ratio and fine-tuning of TAA additive result in a highly crystalline, large grain size and smooth surface of the (MA0.5FA0.5)PbI3 perovskite film. These highly uniform thin films with 850 nm grain size offered a superior interaction between the perovskite material and the electron transport layer (ETL) and a longer lifetime yielding a high PCE. The (MA0.5FA0.5)PbI3+1% TAA-based champion device exhibited the highest PCE of 21.29% for a small area (0.09 cm2) and 18.32% PCE for a large area (1 cm2). The TAA-assisted devices exhibited high stability with >85% retention over 500 h. These results suggest that the (MA0.5FA0.5)PbI3 along with the 1% TAA additive is a promising absorber layer that can produce >21% PCE. 相似文献
2.
Xingtao Wang Yong Wang Taiyang Zhang Xiaomin Liu Yixin Zhao 《Angewandte Chemie (International ed. in English)》2020,59(4):1469-1473
The reduced dimension perovskite including 2D perovskites are one of the most promising strategies to stabilize lead halide perovskite. A mixed‐cation 2D perovskite based on a steric phenyltrimethylammonium (PTA) cation is presented. The PTA‐MA mixed‐cation 2D perovskite of PTAMAPbI4 can be formed on the surface of MAPbI3 (PTAI‐MAPbI3) by controllable PTAI intercalation by either spin coating or soaking. The PTAMAPbI4 capping layer can not only passivate PTAI‐MAPbI3 perovskite but also act as MA+ locker to inhibit MAI extraction and significantly enhance the stability. The highly stable PTAI‐MAPbI3 based perovskite solar cells exhibit a reproducible photovoltaic performance with a champion PCE of 21.16 %. Such unencapsulated devices retain 93 % of initial efficiency after 500 h continuous illumination. This steric mixed‐cation 2D perovskite as MA+ locker to stabilize the MAPbI3 is a promising strategy to design stable and high‐performance hybrid lead halide perovskites. 相似文献
3.
《Mendeleev Communications》2021,31(4):456-458
The thin MAPbI3 and MA0.15FA0.75Cs0.1PbI3 perovskite films have strong nonlinear absorption with coefficients of 443 ± 20 and 830 ± 50 cm GW–1, respectively, due to two-photon absorption at 1064 nm. The photochemical degradation of perovskite films was observed upon irradiation with femtosecond pulses at 532 nm, and the depth of photodegradation decreased in perovskite films protected with a PMMA polymer layer. 相似文献
4.
Yuhang Liu Seckin Akin Alexander Hinderhofer Felix T. Eickemeyer Hongwei Zhu Ji‐Youn Seo Jiahuan Zhang Frank Schreiber Hong Zhang Shaik M. Zakeeruddin Anders Hagfeldt M. Ibrahim Dar Michael Grtzel 《Angewandte Chemie (International ed. in English)》2020,59(36):15688-15694
As a result of their attractive optoelectronic properties, metal halide APbI3 perovskites employing formamidinium (FA+) as the A cation are the focus of research. The superior chemical and thermal stability of FA+ cations makes α‐FAPbI3 more suitable for solar‐cell applications than methylammonium lead iodide (MAPbI3). However, its spontaneous conversion into the yellow non‐perovskite phase (δ‐FAPbI3) under ambient conditions poses a serious challenge for practical applications. Herein, we report on the stabilization of the desired α‐FAPbI3 perovskite phase by protecting it with a two‐dimensional (2D) IBA2FAPb2I7 (IBA=iso‐butylammonium overlayer, formed via stepwise annealing. The α‐FAPbI3/IBA2FAPb2I7 based perovskite solar cell (PSC) reached a high power conversion efficiency (PCE) of close to 23 %. In addition, it showed excellent operational stability, retaining around 85 % of its initial efficiency under severe combined heat and light stress, that is, simultaneous exposure with maximum power tracking to full simulated sunlight at 80 °C over 500 h. 相似文献
5.
Mixed‐Halide CH3NH3PbI3−xXx (X=Cl,Br, I) Perovskites: Vapor‐Assisted Solution Deposition and Application as Solar Cell Absorbers 下载免费PDF全文
Rahime Sedighi Dr. Fariba Tajabadi Saeed Shahbazi Somayeh Gholipour Dr. Nima Taghavinia 《Chemphyschem》2016,17(15):2382-2388
There have been recent reports on the formation of single‐halide perovskites, CH3NH3PbX3 (X=Cl, Br, I), by means of vapor‐assisted solution processing. Herein, the successful formation of mixed‐halide perovskites (CH3NH3PbI3?xXx) by means of a vapor‐assisted solution method at ambient atmosphere is reported. The perovskite films are synthesized by exposing PbI2 film to CH3NH3X (X=I, Br, or Cl) vapor. The prepared perovskite films have uniform surfaces with good coverage, as confirmed by SEM images. The inclusion of chlorine and bromine into the structure leads to a lower temperature and shorter reaction time for optimum perovskite film formation. In the case of CH3NH3PbI3?xClx, the optimum reaction temperature is reduced to 100 °C, and the resulting phases are CH3NH3PbI3 (with trace Cl) and CH3NH3PbCl3 with a ratio of about 2:1. In the case of CH3NH3PbI3?xBrx, single‐phase CH3NH3PbI2Br is formed in a considerably shorter reaction time than that of CH3NH3PbI3. The mesostructured perovskite solar cells based on CH3NH3PbI3 films show the best optimal power conversion efficiency of 13.5 %, whereas for CH3NH3PbI3?xClx and CH3NH3PbI3?xBrx the best recorded efficiencies are 11.6 and 10.5 %, respectively. 相似文献
6.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(26):7782-7786
Methylammonium‐mediated phase‐evolution behavior of FA1−xMAxPbI3 mixed‐organic‐cation perovskite (MOCP) is studied. It is found that by simply enriching the MOCP precursor solutions with excess methylammonium cations, the MOCPs form via a dynamic composition‐tuning process that is key to obtaining MOCP thin films with superior properties. This simple chemical approach addresses several key challenges, such as control over phase purity, uniformity, grain size, composition, etc., associated with the solution‐growth of MOCP thin films with targeted compositions. 相似文献
7.
Chongwen Li Dr. Yuanyuan Zhou Dr. Li Wang Yue Chang Yingxia Zong Dr. Lioz Etgar Dr. Guanglei Cui Prof. Nitin P. Padture Dr. Shuping Pang 《Angewandte Chemie (International ed. in English)》2017,56(26):7674-7678
Methylammonium-mediated phase-evolution behavior of FA1−xMAxPbI3 mixed-organic-cation perovskite (MOCP) is studied. It is found that by simply enriching the MOCP precursor solutions with excess methylammonium cations, the MOCPs form via a dynamic composition-tuning process that is key to obtaining MOCP thin films with superior properties. This simple chemical approach addresses several key challenges, such as control over phase purity, uniformity, grain size, composition, etc., associated with the solution-growth of MOCP thin films with targeted compositions. 相似文献
8.
Jie Zhou Xinxing Yin Zihao Dong Amjad Ali Zhaoning Song Niraj Shrestha Sandip Singh Bista Qinye Bao Randy J. Ellingson Yanfa Yan Weihua Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):13855-13859
Organic p‐type semiconductors with tunable structures offer great opportunities for hybrid perovskite solar cells (PVSCs). We report herein two dithieno[3,2‐b:2′,3′‐d]pyrrole (DTP) cored molecular semiconductors prepared through π‐conjugation extension and an N‐alkylation strategy. The as‐prepared conjugated molecules exhibit a highest occupied molecular orbital (HOMO) level of ?4.82 eV and a hole mobility up to 2.16×10?4 cm2 V?1 s?1. Together with excellent film‐forming and over 99 % photoluminescence quenching efficiency on perovskite, the DTP based semiconductors work efficiently as hole‐transporting materials (HTMs) for n‐i‐p structured PVSCs. Their dopant‐free MA0.7FA0.3PbI2.85Br0.15 devices exhibit a power conversion efficiency over 20 %, representing one of the highest values for un‐doped molecular HTMs based PVSCs. This work demonstrates the great potential of using a DTP core in designing efficient semiconductors for dopant‐free PVSCs. 相似文献
9.
Li Hong Jovana V. Mili Paramvir Ahlawat Marko Mladenovi Dominik J. Kubicki Farzaneh Jahanabkhshi Dan Ren María C. Glvez‐Rueda Marco A. Ruiz‐Preciado Amita Ummadisingu Yuhang Liu Chengbo Tian Linfeng Pan Shaik M. Zakeeruddin Anders Hagfeldt Ferdinand C. Grozema Ursula Rothlisberger Lyndon Emsley Hongwei Han Michael Graetzel 《Angewandte Chemie (International ed. in English)》2020,59(12):4691-4697
Formamidinium (FA) lead iodide perovskite materials feature promising photovoltaic performances and superior thermal stabilities. However, conversion of the perovskite α‐FAPbI3 phase to the thermodynamically stable yet photovoltaically inactive δ‐FAPbI3 phase compromises the photovoltaic performance. A strategy is presented to address this challenge by using low‐dimensional hybrid perovskite materials comprising guaninium (G) organic spacer layers that act as stabilizers of the three‐dimensional α‐FAPbI3 phase. The underlying mode of interaction at the atomic level is unraveled by means of solid‐state nuclear magnetic resonance spectroscopy, X‐ray crystallography, transmission electron microscopy, molecular dynamics simulations, and DFT calculations. Low‐dimensional‐phase‐containing hybrid FAPbI3 perovskite solar cells are obtained with improved performance and enhanced long‐term stability. 相似文献
10.
Li‐Yuan Wu Yan‐Fei Mu Xiao‐Xuan Guo Wen Zhang Zhi‐Ming Zhang Min Zhang Tong‐Bu Lu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(28):9591-9595
Improving the stability of lead halide perovskite quantum dots (QDs) in a system containing water is the key for their practical application in artificial photosynthesis. Herein, we encapsulate low‐cost CH3NH3PbI3 (MAPbI3) perovskite QDs in the pores of earth‐abundant Fe‐porphyrin based metal organic framework (MOF) PCN‐221(Fex) by a sequential deposition route, to construct a series of composite photocatalysts of MAPbI3@PCN‐221(Fex) (x=0–1). Protected by the MOF the composite photocatalysts exhibit much improved stability in reaction systems containing water. The close contact of QDs to the Fe catalytic site in the MOF, allows the photogenerated electrons in the QDs to transfer rapidly the Fe catalytic sites to enhance the photocatalytic activity for CO2 reduction. Using water as an electron source, MAPbI3@PCN‐221(Fe0.2) exhibits a record‐high total yield of 1559 μmol g?1 for photocatalytic CO2 reduction to CO (34 %) and CH4 (66 %), 38 times higher than that of PCN‐221(Fe0.2) in the absence of perovskite QDs. 相似文献
11.
All‐Inorganic CsPb1−xGexI2Br Perovskite with Enhanced Phase Stability and Photovoltaic Performance 下载免费PDF全文
Fu Yang Daisuke Hirotani Dr. Gaurav Kapil Dr. Muhammad Akmal Kamarudin Dr. Chi Huey Ng Dr. Yaohong Zhang Prof. Dr. Qing Shen Prof. Dr. Shuzi Hayase 《Angewandte Chemie (International ed. in English)》2018,57(39):12745-12749
Compared with organic‐inorganic perovskites, all‐inorganic cesium‐based perovskites without volatile organic compounds have gained extensive interests because of the high thermal stability. However, they have a problem on phase transition from cubic phase (active for photo‐electric conversion) to orthorhombic phase (inactive for photo‐electric conversion) at room temperature, which has hindered further progress. Herein, novel inorganic CsPb1?xGexI2Br perovskites were prepared in humid ambient atmosphere without a glovebox. The phase stability of the all‐inorganic perovskite was effectively enhanced after germanium addition. In addition, the highest power conversion efficiency of 10.8 % with high open‐circuit voltage (VOC) of 1.27 V in a planar solar cell based on CsPb0.8Ge0.2I2Br perovskite was achieved. Furthermore, the highest VOC up to 1.34 V was obtained by CsPb0.7Ge0.3I2Br perovskite, which is a remarkable record in the field of all‐inorganic perovskite solar cells. More importantly, all the photovoltaic parameters of CsPb0.8Ge0.2I2Br perovskite solar cells showed nearly no decay after 7 h measurement in 50–60 % relative humidity without encapsulation. 相似文献
12.
Dr. Chuanzhao Li Renlong Zhu Zhe Yang Jing Lai Dr. Junjun Tan Prof. Yi Luo Prof. Shuji Ye 《Angewandte Chemie (International ed. in English)》2023,62(7):e202214208
We demonstrate that an ordered 2D perovskite can significantly boost the photoelectric performance of 2D/3D perovskite heterostructures. Using selective fluorination of phenyl-ethyl ammonium (PEA) lead iodide to passivate 3D FA0.8Cs0.2PbI3, we find that the 2D/3D perovskite heterostructures passivated by a higher ordered 2D perovskite have lower Urbach energy, yielding a remarkable increase in photoluminescence (PL) intensity, PL lifetime, charge-carrier mobilities (ϕμ), and carrier diffusion length (LD) for a certain 2D perovskite content. High performance with an ultralong PL lifetime of ≈1.3 μs, high ϕμ of ≈18.56 cm2 V−1 s−1, and long LD of ≈7.85 μm is achieved in the 2D/3D films when passivated by 16.67 % para-fluoro-PEA2PbI4. This carrier diffusion length is comparable to that of some perovskite single crystals (>5 μm). These findings provide key missing information on how the organic cations of 2D perovskites influence the performance of 2D/3D perovskite heterostructures. 相似文献
13.
Benign‐by‐Design Solventless Mechanochemical Synthesis of Three‐, Two‐, and One‐Dimensional Hybrid Perovskites 下载免费PDF全文
Alexander D. Jodlowski Dr. Alfonso Yépez Prof. Rafael Luque Prof. Luis Camacho Prof. Gustavo de Miguel 《Angewandte Chemie (International ed. in English)》2016,55(48):14972-14977
Organic–inorganic hybrid perovskites have attracted significant attention owing to their extraordinary optoelectronic properties with applications in the fields of solar energy, lighting, photodetectors, and lasers. The rational design of these hybrid materials is a key factor in the optimization of their performance in perovskite‐based devices. Herein, a mechanochemical approach is proposed as a highly efficient, simple, and reproducible method for the preparation of four types of hybrid perovskites, which were obtained in large amounts as polycrystalline powders with high purity and excellent optoelectronics properties. Two archetypal three‐dimensional (3D) perovskites (MAPbI3 and FAPbI3) were synthesized, together with a bidimensional (2D) perovskite (Gua2PbI4) and a “double‐chain” one‐dimensional (1D) perovskite (GuaPbI3), whose structure was elucidated by X‐ray diffraction. 相似文献
14.
Dr. Yangning Zhang Omar F. Aly Anastacia De Gorostiza Thana Shuga Aldeen Allison J. Segapeli Prof. Dr. Brian A. Korgel 《Angewandte Chemie (International ed. in English)》2023,62(31):e202306005
Cesium methylammonium lead iodide (CsxMA1−xPbI3) nanocrystals were obtained with a wide range of A-site Cs-MA compositions by post-synthetic, room temperature cation exchange between CsPbI3 nanocrystals and MAPbI3 nanocrystals. The alloyed CsxMA1−xPbI3 nanocrystals retain their photoactive perovskite phase with incorporated Cs content, x, as high as 0.74 and the expected composition-tunable photoluminescence (PL). Excess methylammonium oleate from the reaction mixture in the MAPbI3 nanocrystal dispersions was necessary to obtain fast Cs-MA cation exchange. The phase transformation and degradation kinetics of films of CsxMA1−xPbI3 nanocrystals were measured and modeled using an Avrami expression. The transformation kinetics were significantly slower than those of the parent CsPbI3 and MAPbI3 nanocrystals, with Avrami rate constants, k, at least an order of magnitude smaller. These results affirm that A-site cation alloying is a promising strategy for stabilizing iodide-based perovskites. 相似文献
15.
Methylamine‐Gas‐Induced Defect‐Healing Behavior of CH3NH3PbI3 Thin Films for Perovskite Solar Cells 下载免费PDF全文
Dr. Zhongmin Zhou Zaiwei Wang Yuanyuan Zhou Dr. Shuping Pang Dong Wang Dr. Hongxia Xu Dr. Zhihong Liu Prof. Nitin P. Padture Dr. Guanglei Cui 《Angewandte Chemie (International ed. in English)》2015,54(33):9705-9709
We report herein the discovery of methylamine (CH3NH2) induced defect‐healing (MIDH) of CH3NH3PbI3 perovskite thin films based on their ultrafast (seconds), reversible chemical reaction with CH3NH2 gas at room temperature. The key to this healing behavior is the formation and spreading of an intermediate CH3NH3PbI3?xCH3NH2 liquid phase during this unusual perovskite–gas interaction. We demonstrate the versatility and scalability of the MIDH process, and show dramatic enhancement in the performance of perovskite solar cells (PSCs) with MIDH. This study represents a new direction in the formation of defect‐free films of hybrid perovskites. 相似文献
16.
Dr. Wenming Tian Rongrong Cui Dr. Jing Leng Junxue Liu Yajuan Li Chunyi Zhao Prof. Dr. Jun Zhang Prof. Dr. Weiqiao Deng Prof. Dr. Tianquan Lian Prof. Dr. Shengye Jin 《Angewandte Chemie (International ed. in English)》2016,55(42):13067-13071
Although the power conversion efficiency of perovskite solar cells has improved rapidly, a rational path for further improvement remains unclear. The effect of large morphological heterogeneity of polycrystalline perovskite films on their device performance by photoluminescence (PL) microscopy has now been studied. Contrary to the common belief on the deleterious effect of morphological heterogeneity on carrier lifetimes and diffusivities, in neat CH3NH3PbI3(Cl) polycrystalline perovskite films, the local (intra‐grain) carrier diffusivities in different grains are all surprisingly high (1.5 to 3.3 cm2 s?1; comparable to bulk single‐crystals), and the local carrier lifetimes are long (ca. 200 ns) and surprisingly homogenous among grains, and uniform across grain boundary and interior. However, there is a large heterogeneity of carrier extraction efficiency at the perovskite grain–electrode interface. Improving homogeneity at perovskite grain–electrode contacts is thus a promising direction for improving the performance of perovskite thin‐film solar cells. 相似文献
17.
An Above‐Room‐Temperature Ferroelectric Organo–Metal Halide Perovskite: (3‐Pyrrolinium)(CdCl3) 下载免费PDF全文
Dr. Heng‐Yun Ye Dr. Yi Zhang Dr. Da‐Wei Fu Prof. Ren‐Gen Xiong 《Angewandte Chemie (International ed. in English)》2014,53(42):11242-11247
Hybrid organo–metal halide perovskite materials, such as CH3NH3PbI3, have been shown to be some of the most competitive candidates for absorber materials in photovoltaic (PV) applications. However, their potential has not been completely developed, because a photovoltaic effect with an anomalously large voltage can be achieved only in a ferroelectric phase, while these materials are probably ferroelectric only at temperatures below 180 K. A new hexagonal stacking perovskite‐type complex (3‐pyrrolinium)(CdCl3) exhibits above‐room‐temperature ferroelectricity with a Curie temperature Tc=316 K and a spontaneous polarization Ps=5.1 μC cm?2. The material also exhibits antiparallel 180° domains which are related to the anomalous photovoltaic effect. The open‐circuit photovoltage for a 1 mm‐thick bulky crystal reaches 32 V. This finding could provide a new approach to develop solar cells based on organo–metal halide perovskites in photovoltaic research. 相似文献
18.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(50):16283-16288
3D and 2D hybrid perovskites, which have been known for more than 20 years, have emerged recently as promising materials for optoelectronic applications, particularly the 3D compound (CH3NH3)PbI3 (MAPI). The discovery of a new family of hybrid perovskites called d ‐MAPI is reported: the association of PbI2 with both methyl ammonium (MA+) and hydroxyethyl ammonium (HEA+) cations leads to a series of five compounds with general formulation (MA)1−2.48x(HEA)3.48x[Pb1−xI3−x]. These materials, which are lead‐ and iodide‐deficient compared to MAPI while retaining 3D architecture, can be considered as a bridge between the 2D and 3D materials. Moreover, they can be prepared as crystallized thin films by spin‐coating. These new 3D materials appear very promising for optoelectronic applications, not only because of their reduced lead content, but also in account of the large flexibility of their chemical composition through potential substitutions of MA+, HEA+, Pb2+ and I− ions. 相似文献
19.
Liguo Gao Fei Zhang Xihan Chen Chuanxiao Xiao Bryon W. Larson Sean P. Dunfield Joseph J. Berry Kai Zhu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(34):11863-11867
Organic‐inorganic hybrid two‐dimensional (2D) perovskites (n≤5) have recently attracted significant attention because of their promising stability and optoelectronic properties. Normally, 2D perovskites contain a monocation [e.g., methylammonium (MA+) or formamidinium (FA+)]. Reported here for the first time is the fabrication of 2D perovskites (n=5) with mixed cations of MA+, FA+, and cesium (Cs+). The use of these triple cations leads to the formation of a smooth, compact surface morphology with larger grain size and fewer grain boundaries compared to the conventional MA‐based counterpart. The resulting perovskite also exhibits longer carrier lifetime and higher conductivity in triple cation 2D perovskite solar cells (PSCs). The power conversion efficiency (PCE) of 2D PSCs with triple cations was enhanced by more than 80 % (from 7.80 to 14.23 %) compared to PSCs fabricated with a monocation. The PCE is also higher than that of PSCs based on binary cation (MA+‐FA+ or MA+‐Cs+) 2D structures. 相似文献
20.
Bin Yang Feng Hong Junsheng Chen Yuxuan Tang Li Yang Youbao Sang Xusheng Xia Jingwei Guo Haixiang He Songqiu Yang Weiqiao Deng Keli Han 《Angewandte Chemie (International ed. in English)》2019,58(8):2278-2283
A series of lead‐free double perovskite nanocrystals (NCs) Cs2AgSb1?yBiyX6 (X: Br, Cl; 0≤y≤1) is synthesized. In particular, the Cs2AgSbBr6 NCs is a new double perovskite material that has not been reported for the bulk form. Mixed Ag–Sb/Bi NCs exhibit enhanced stability in colloidal solution compared to Ag–Bi or Ag–Sb NCs. Femtosecond transient absorption studies indicate the presence of two prominent fast trapping processes in the charge‐carrier relaxation. The two fast trapping processes are dominated by intrinsic self‐trapping (ca. 1–2 ps) arising from giant exciton–phonon coupling and surface‐defect trapping (ca. 50–100 ps). Slow hot‐carrier relaxation is observed at high pump fluence, and the possible mechanisms for the slow hot‐carrier relaxation are also discussed. 相似文献