π-Extended Nonfullerene Acceptor for Compressed Molecular Packing in Organic Solar Cells To Achieve over 20% Efficiency

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(17), С. 12011 - 12019

Опубликована: Апрель 19, 2024

Organic photovoltaics (OPVs) suffer from a trade-off between efficient charge transport and suppressed nonradiative recombination due to the aggregation-induced luminance quenching of organic semiconductors. To resolve this grand challenge, π-extended nonfullerene acceptor (NFA) B6Cl with large voids among honeycomb network is designed introduced into photovoltaic systems. We find that presence small amount (i.e., 0.5 or 1 wt %) can compress molecular packing host L8-BO, leading shortened π–π stacking distance 3.59 3.50 Å (that will improve transport) together ordered alkyl chain inhibit energy loss C–C C–H bonds vibrations), as validated by high-energy X-ray scattering measurements. This morphology transformation ultimately results in simultaneously improved JSC, FF, VOC OPVs. As result, maximum PCEs PM6:L8-BO D18:L8-BO are increased 19.1 19.3% 19.8 20.2%, respectively, which highest values for single-junction The university increase performance OPVs further evidenced range polymer:NFA

Язык: Английский

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Orientated crystallization of FA-based perovskite via hydrogen-bonded polymer network for efficient and stable solar cells

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Фев. 2, 2023

Incorporating mixed ion is a frequently used strategy to stabilize black-phase formamidinum lead iodide perovskite for high-efficiency solar cells. However, these devices commonly suffer from photoinduced phase segregation and humidity instability. Herein, we find that the underlying reason halide perovskites generally fail grow into homogenous high-crystalline film, due multiple pathways of crystal nucleation originating various intermediate phases in film-forming process. Therefore, design multifunctional fluorinated additive, which restrains complicated promotes orientated crystallization α-phase perovskite. Furthermore, additives in-situ polymerize during film formation form hydrogen-bonded network α-phase. Remarkably, polymerized endow strongly hydrophobic effect bare against liquid water 5 min. The unencapsulated achieve 24.10% efficiency maintain >95% initial 1000 h under continuous sunlight soaking 2000 at air ambient ~50% humid, respectively.

Язык: Английский

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Degradation pathways in perovskite solar cells and how to meet international standards

Communications Materials, Год журнала: 2022, Номер 3(1)

Опубликована: Авг. 29, 2022

Abstract Commercialization is widely believed to be achievable for metal halide perovskite solar cells with high efficiency and low fabrication cost. However, stability remains a key obstacle them compete established photovoltaic technologies. The community relies on the International Electrotechnical Commission (IEC) standard minimum assessment any commercialized cell. In this review, we summarize main degradation mechanisms of results achieving sufficient meet IEC standards. We also limitations evaluating cell commercialization potential within framework current standard, discuss importance outdoor testing.

Язык: Английский

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21.15%‐Efficiency and Stable γ ‐CsPbI₃ Perovskite Solar Cells Enabled by an Acyloin Ligand

Advanced Materials, Год журнала: 2023, Номер 35(12)

Опубликована: Янв. 9, 2023

Cesium lead triiodide (CsPbI3 ) is a promising light-absorbing material for constructing perovskite solar cells (PSCs) owing to its favorable bandgap and thermal tolerance. However, the high density of defects in CsPbI3 film not only act as recombination centers, but also facilitate ion migration, leading lower PCE inferior stability compared with state-of-the-art organic-inorganic hybrid PSC counterpart. Theoretical analyses suggest that effective suppression helpful improving device performance. Herein, stable efficient γ -CsPbI3 PSCs are demonstrated by developing an acyloin ligand (1,2-di(thiophen-2-yl)ethane-1,2-dione (DED)) phase stabilizer defect passivator. The experiment calculation results confirm carbonyl thienyl DED can synergistically interact forming chelate effectively passivate Pb-related further suppress migration. Consequently, DED-treated yield champion 21.15%, which one highest among all reported date. In addition, unencapsulated DED-CsPbI3 retain 94.9% itsinitial when stored under ambient conditions 1000 h 92.8% initial constant illumination 250 h.

Язык: Английский

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Over 24% Efficient Poly(vinylidene fluoride) (PVDF)‐Coordinated Perovskite Solar Cells with a Photovoltage up to 1.22 V

Advanced Functional Materials, Год журнала: 2022, Номер 33(6)

Опубликована: Дек. 11, 2022

Abstract Recently, organic–inorganic metal halide perovskite solar cells (PSCs) have achieved rapid improvement, however, the efficiencies are still behind Shockley–Queisser theory mainly due to their high energy loss ( E LOSS ) in open‐circuit voltage V OC ). Due polycrystalline nature of solution‐prepared films, defects at grain boundaries as non‐radiative recombination centers greatly affect and limit device efficiency. Herein, poly(vinylidene fluoride) (PVDF) is introduced polymer‐templates film, where fluorine atoms PVDF network can form strong hydrogen‐bonds with organic cations coordinate bonds Pb 2+ . The interaction between perovksite enables slow crystal growth efficient defect passivation, which effectively reduce non‐radiation minimize PVDF‐based PSCs achieve a champion efficiency 24.21% excellent 1.22 V, one highest values reported for FAMAPb(I/Br) 3 ‐based PSCs. Furthermore, hydrophobic endow humidity stability, unencapsulated cell maintain initial >90% 2500 h under air ambient ≈50% humid consistently 1.20 V.

Язык: Английский

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Reduced 0.418 V V_OC-deficit of 1.73 eV wide-bandgap perovskite solar cells assisted by dual chlorides for efficient all-perovskite tandems

Energy & Environmental Science, Год журнала: 2023, Номер 16(5), С. 2080 - 2089

Опубликована: Янв. 1, 2023

Synergistic effects of lead chloride and phenethylammonium suppress the phase segregation non-radiative recombination in 1.73 eV wide- E g perovskite solar cells (PSCs), leading to a significantly reduced V OC -deficit 0.418 V.

Язык: Английский

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Developments of Highly Efficient Perovskite Solar Cells

Accounts of Materials Research, Год журнала: 2023, Номер 4(8), С. 716 - 725

Опубликована: Июль 21, 2023

ConspectusAfter developments in just more than a decade, the power conversion efficiency (PCE) of single junction perovskite solar cells (PSCs) has achieved record 26.0%. Such rapid progress PSCs technology is mainly attributed to excellent optoelectronic properties and facile solution-processed fabrication. Starting from birth up present, various methods have been attempted improve performance and/or stability PSCs. The first photovoltaic devices very low efficiency, poor quality film upon mesoporous substrate. There then are large amounts work aiming at high-quality light-absorber films with pin-free, dense, homogeneous morphology high crystallinity. Hereafter, carrier transport materials/layers (CTLs) based on different device structures had become an important issue. stable CTLs electrical matched energy levels desired for efficient Besides growth control employment advanced CTLs, main studies mitigation all kinds defects PSCs, including charge traps bulk, interface between adjacent grain boundaries located dangling bonds as well halide loss defects. All these can not only cause nonradiation recombination but also provide extra pathway ionic migration, which leads irreversible degradation film. And current trying push industrial application, since long-term high-efficiency count same importance apparent fact that literature about PSC fabrication experiment conditions, gives it reproducibility. Herein, conception motivation valuable. It necessary share research detail by individual laboratories better communication this rapidly developed field. could be concluded there three steps achieve such appreciable stability: 1) modulation quality; 2) development PSCs; 3) bulk interfaces. basic track In Account, we will briefly review milestones early period Then, focus our group coauthors' representative following above order technology. mechanisms motivations improved stages discussed. Finally, comprehensive summary deep perspectives proposed. future directions practical application

Язык: Английский

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Highly Efficient Perovskite/Organic Tandem Solar Cells Enabled by Mixed‐Cation Surface Modulation

Advanced Materials, Год журнала: 2023, Номер 35(49)

Опубликована: Авг. 7, 2023

Perovskite/organic tandem solar cells (POTSCs) are gaining attention due to their easy fabrication, potential surpass the S-Q limit, and superior flexibility. However, low power conversion efficiencies (PCEs) of wide bandgap (Eg) perovskite (PVSCs) have hindered development. This work presents a novel effective mixed-cation passivation strategy (CE) passivate various types traps in wide-Eg perovskite. The complementary effect 4-trifluoro phenethylammonium (CF3 -PEA+ , denoted as CA+ ) ethylenediammonium (EDA2+ EA2+ reduces both electron/hole defect densities non-radiative recombination rate, resulting record open-circuit voltage (Voc PVSCs (1.35 V) high fill factor (FF) 83.29%. These improvements lead PCE 24.47% when applied fabricated POTSCs, highest date. Furthermore, unencapsulated POTSCs exhibit excellent photo thermal stability, retaining over 90% initial after maximum point (MPP) tracking or exposure 60 °C for 500 h. findings imply that synergic surface passivators is promising achieve high-efficiency stable corresponding POTSCs.

Язык: Английский

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Surface Energy Engineering of Buried Interface for Highly Stable Perovskite Solar Cells with Efficiency Over 25%

Advanced Materials, Год журнала: 2023, Номер 36(2)

Опубликована: Окт. 21, 2023

The abundant oxygen-related defects (e.g., O vacancies, O-H) in the TiO

Язык: Английский

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A Binary Solution Strategy Enables High-Efficiency Quasi-2D Perovskite Solar Cells with Excellent Thermal Stability

ACS Nano, Год журнала: 2023, Номер 17(15), С. 14632 - 14643

Опубликована: Июль 21, 2023

Quasi-two-dimensional (2D) perovskites are highly promising light-harvesting materials for commercialization of perovskite solar cells (PSCs) owing to the excellent stability. However, coexistence multiple n-value species in 2D often causes increased complexities crystallization that can negatively affect eventual photovoltaic performance. Herein, we present a binary solution based strategy via introducing nontoxic and widely accessible CH3COOH (HAc) as co-solvent preparing high-quality films. Based on model system, (AA)2MA4Pb5I16 (n = 5), show prenucleation grain growth kinetics appreciably modified with HAc, which benefits from strong electron-donating ability HAc key component PbI2, leading formation favorable cluster aggregates resultant modulation crystal growth. With HAc-based method, devices yield boosted efficiency 18.55% an impressive photovoltage 1.26 V. The champion exhibit supreme thermal stability, showing <3% degradation under continuous aging 800 h.

Язык: Английский

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