Manipulating the D:A interfacial energetics and intermolecular packing for 19.2% efficiency organic photovoltaics

Energy & Environmental Science, Год журнала: 2022, Номер 15(6), С. 2537 - 2544

Опубликована: Янв. 1, 2022

A novel electron acceptor, BTP-H2, demonstrates a high efficiency of 18.5% with V oc 0.932 V. It also enables the ternary device to yield an 19.2%, ranking highest among single-junction organic photovoltaics.

Язык: Английский

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Intrinsic efficiency limits in low-bandgap non-fullerene acceptor organic solar cells

Nature Materials, Год журнала: 2020, Номер 20(3), С. 378 - 384

Опубликована: Окт. 23, 2020

Язык: Английский

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Emerging Approaches in Enhancing the Efficiency and Stability in Non‐Fullerene Organic Solar Cells

Advanced Energy Materials, Год журнала: 2020, Номер 10(47)

Опубликована: Ноя. 9, 2020

Abstract The past three years have witnessed rapid growth in the field of organic solar cells (OSCs) based on non‐fullerene acceptors (NFAs), with intensive efforts being devoted to material development, device engineering, and understanding physics. power conversion efficiency single‐junction OSCs has now reached high values over 18%. boost results from a combination promising features NFA OSCs, including efficient charge generation, good transport, small voltage losses. In addition efficiency, stability, which is another critical parameter for commercialization also been investigated. This review summarizes recent advances field, highlights approaches enhancing stability discusses possible strategies further OSCs.

Язык: Английский

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The Energy Level Conundrum of Organic Semiconductors in Solar Cells

Advanced Materials, Год журнала: 2022, Номер 34(35)

Опубликована: Июль 5, 2022

The frontier molecular energy levels of organic semiconductors are decisive for their fundamental function and efficiency in optoelectronics. However, the precise determination these variation when using different techniques makes it hard to compare establish design rules. In this work, 33 via cyclic voltammetry (CV), density functional theory, ultraviolet photoelectron spectroscopy, low-energy inverse spectroscopy determined. Solar cells fabricated obtain key device parameters relate them significant differences offsets obtained from methods. contrast CV, photovoltaic gap measured (PES) correlates well with experimental VOC . It is demonstrated that high-performing systems such as PM6:Y6 WF3F:Y6, which previously reported have negligible ionization (IE) (ΔIE), possess sizable ΔIE ≈0.5 eV, determined by PES. Using various D-A blends, plays a role charge generation. earlier reports, shown vanishing detrimental performance. Overall, findings solid base reliably evaluating material energetics interpreting property-performance relationships solar cells.

Язык: Английский

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Non‐Radiative Recombination Energy Losses in Non‐Fullerene Organic Solar Cells

Advanced Functional Materials, Год журнала: 2022, Номер 32(19)

Опубликована: Фев. 5, 2022

Abstract Impressive short‐circuit current density and fill factor have been achieved simultaneously in single‐junction organic solar cells (OSCs) with the emergence of high‐performance non‐fullerene acceptors. However, power conversion efficiencies (PCEs) OSCs still lag behind those inorganic perovskite cells, mainly due to modest open‐circuit voltage ( V OC ) imposed by relatively large energy loss E ). Generally, can be divided into three parts. Among them, Δ 1 is inevitable for all photovoltaic depends on optical bandgap while radiative recombination loss, 2 , approach negligible value via finely matching donor acceptor material blend. The non‐radiative 3 becomes main barrier further reduce thus enhance PCE acceptor‐based OSCs. In this review, recent studies achievements about summarized from aspects design, morphology manipulation, ternary strategy, mechanism, theoretical study. It hoped that review helps get a deep understanding boost advance study

Язык: Английский

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From Solution to Thin Film: Molecular Assembly of π-Conjugated Systems and Impact on (Opto)electronic Properties

Chemical Reviews, Год журнала: 2023, Номер 123(13), С. 8395 - 8487

Опубликована: Июнь 5, 2023

The assembly of conjugated organic molecules from solution to solid-state plays a critical role in determining the thin film morphology and optoelectronic properties solution-processed electronics photovoltaics. During evaporative processing, π-conjugated systems can assemble via various forms intermolecular interactions, forming distinct aggregate structures that drastically tune charge transport landscape solid-state. In blend composed donor polymer acceptor molecules, neat materials couples with phase separation crystallization processes, leading complex transition pathways which govern morphology. this review, we provide an in-depth review molecular processes polymers nonfullerene small molecule acceptors discuss their impact on properties. We then shift our focus relevant solar cells fundamentals highlight how processing conditions affect device performance.

Язык: Английский

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Novel Oligomer Enables Green Solvent Processed 17.5% Ternary Organic Solar Cells: Synergistic Energy Loss Reduction and Morphology Fine‐Tuning

Advanced Materials, Год журнала: 2022, Номер 34(10)

Опубликована: Янв. 8, 2022

The large non-radiative recombination is the main factor that limits state-of-the-art organic solar cells (OSCs). In this work, two novel structurally similar oligomers (named 5BDTBDD and 5BDDBDT) with D-A-D-A-D A-D-A-D-A configuration are synthesized for high-performance ternary OSCs low energy loss. As third components, these PM6 analogue effectively suppress in OSCs. Although highest occupied molecular orbital (HOMO) levels of 5BDDBDT higher than PM6, enabled ultra-high electroluminescence quantum efficiency (EQEEL ) 0.05% improved VOC , indicating suppressing overweighs common belief deeper HOMO requirement component selection. Moreover, different compatibility BTP-BO4Cl fine-tunes active layer morphology synergistic effects. devices based on PM6:5BDTBDD:BTPBO4Cl PM6:5BDDBDT:BTP-BO4Cl achieve a significantly PCEs 17.54% 17.32%, representing state-of-the art processed by green solvent o-xylene. strategy using oligomer as also has very wide composition tolerance This first work demonstrates compatible D-A type effective provides new understanding synergetic loss mechanisms towards high performance

Язык: Английский

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Mapping the energy level alignment at donor/acceptor interfaces in non-fullerene organic solar cells

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Апрель 19, 2022

Abstract Energy level alignment (ELA) at donor (D) -acceptor (A) heterojunctions is essential for understanding the charge generation and recombination process in organic photovoltaic devices. However, ELA D-A interfaces largely underdetermined, resulting debates on fundamental operating mechanisms of high-efficiency non-fullerene solar cells. Here, we systematically investigate its depth-dependent variation a range donor/non-fullerene-acceptor by fabricating characterizing quasi bilayers planar bilayers. In contrast to previous assumptions, observe significant vacuum (VL) shifts existing interfaces, which are demonstrated be abrupt, extending over only 1–2 layers heterojunctions, attributed interface dipoles induced electrostatic potential differences. The VL result reduced interfacial energetic offsets increased transfer (CT) state energies reconcile conflicting observations large energy inferred from neat films CT - non-fullerene-acceptor systems.

Язык: Английский

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A Wide Bandgap Acceptor with Large Dielectric Constant and High Electrostatic Potential Values for Efficient Organic Photovoltaic Cells

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(25), С. 13686 - 13695

Опубликована: Июнь 13, 2023

Low-bandgap materials have achieved rapid development and promoted the enhancement of power conversion efficiencies (PCEs) organic photovoltaic (OPV) cells. However, design wide-bandgap non-fullerene acceptors (WBG-NFAs), required by indoor applications tandem cells, has been lagging far behind OPV technologies. Here, we designed synthesized two NFAs named ITCC-Cl TIDC-Cl finely optimizing ITCC. In contrast with ITCC ITCC-Cl, can maintain a wider bandgap higher electrostatic potential simultaneously. When blending donor PB2, highest dielectric constant is also obtained in TIDC-Cl-based films, enabling efficient charge generation. Therefore, PB2:TIDC-Cl-based cell possessed high PCE 13.8% an excellent fill factor (FF) 78.2% under air mass 1.5G (AM 1.5G) condition. Furthermore, exciting 27.1% be accomplished PB2:TIDC-Cl system illumination 500 lux (2700 K light-emitting diode). Combined theoretical simulation, based on was fabricated exhibited 20.0%.

Язык: Английский

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Accurate Determination of the Minimum HOMO Offset for Efficient Charge Generation using Organic Semiconducting Alloys

Advanced Energy Materials, Год журнала: 2019, Номер 10(5)

Опубликована: Дек. 16, 2019

Abstract Current research indicates that exciton dissociation into free charge carriers can be achieved in material combinations with the highest occupied molecular orbital (HOMO) offset lowered to 0 eV non‐fullerene organic solar cells. However, quantitative relationship between HOMO and has not been established because of difficulty achieving continuously tunable offsets. Here, binary blends PTQ10:ZITI‐S PTQ10:ZITI‐N are combined form positive negative offsets 0.20 −0.07 eV, respectively. While blend delivers a decent power conversion efficiency (PCE) 10.69% short‐circuit current ( J sc ) 16.94 mA cm −2 , shows much lower PCE 7.06% mainly low 12.03 . Because levels realized semiconducting alloys based on ZITI‐N ZITI‐S acceptors, transformation energy from values is PTQ10:ZITIN:ZITI‐S ternary blends, delivering much‐improved PCEs up 13.26% significant, 74% enhancement 20.93 With detailed investigations, study reveals minimum ≈40 meV required achieve most‐efficient photovoltaic performance.

Язык: Английский

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