Defining Solid Additive's Pivotal Role on Morphology Regulation in Organic Solar Cells Produced by Layer‐by‐layer Deposition

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(22)

Published: March 8, 2024

Abstract Herein, two emerging device optimization methods, solid additive and layer‐by‐layer (LBL) process, for organic solar cells (OSCs) are simultaneously studied. Through traditional blend cast recently proposed identical solvent LBL cast, BDCB (2‐monobromo‐1,3‐dichloro‐bezene), a benzene derivative, is used to improve the performance based on celebrity combination PM6:L8‐BO. The results reveal that finely optimized concentration in PM6 solution can push efficiency of 19.03% compared with only 18.12% while power conversion (PCE) changing trend determined by BDCB's ratio L8‐BO's precursor. morphology characterizations confirm there exists no significant stratification LBL‐processed devices, supported previously reported swelling‐intercalation‐phase separation (SIPS) model. Thereby, additive's 2D considered smart strategy tuning SIPS which various final states. This work not reports cutting‐edge binary OSCs, but also new insight deep understanding method‐based development.

Language: Английский

---

Approaching 20% Efficiency in Ortho‐Xylene Processed Organic Solar Cells by a Benzo[a]phenazine‐Core‐Based 3D Network Acceptor with Large Electronic Coupling and Long Exciton Diffusion Length

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(41)

Published: Aug. 13, 2024

Abstract High‐performance organic solar cells often rely on halogen‐containing solvents, which restrict the photovoltaic industry. Therefore, it is imperative to develop efficient materials compatible with halogen‐free solvents. Herein, a series of benzo[ ]phenazine (BP)‐core‐based small‐molecule acceptors (SMAs) achieved through an isomerization chlorination strategy presented, comprising unchlorinated NA1, 10‐chlorine substituted NA2, 8‐chlorine NA3, and 7‐chlorine NA4. Theoretical simulations highlight NA3's superior orbit overlap length tight molecular packing, attributed interactions between end group BP unit. Furthermore, NA3 demonstrates dense 3D network structures record electronic coupling 104.5 meV. These characteristics empower ortho‐xylene ( o ‐XY) processed PM6:NA3 device power conversion efficiency (PCE) 18.94%, surpassing PM6:NA1 (15.34%), PM6:NA2 (7.18%), PM6:NA4 (16.02%). Notably, significantly lower PCE in excessive self‐aggregation NA2 ‐XY. Importantly, incorporation D18‐Cl into binary blend enhances crystallographic ordering increases exciton diffusion donor phase, resulting ternary 19.75% (certified as 19.39%). findings underscore significance incorporating new electron‐deficient units design SMAs tailored for environmentally benign solvent processing OSCs.

Language: Английский

---

Layer‐by‐Layer Organic Solar Cells Enabled by 1,3,4‐Selenadiazole‐Containing Crystalline Small Molecule with Double‐Fibril Network Morphology

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(21)

Published: March 27, 2024

A double-fibril network of the photoactive layer morphology is recognized as an ideal structure facilitating exciton diffusion and charge carrier transport for high-performance organic solar cells (OSCs). However, in layer-by-layer processed OSCs (LbL-OSCs), polymer donors small molecule acceptors (SMAs) are separately deposited, it challenging to realize a fibril pure SMAs with absence tight interchain entanglement polymers. In this work, crystalline (SMDs), named TDZ-3TR SeDZ-3TR, were designed introduced into L8-BO acceptor solution, forcing phase separation molecular fibrilization. SeDZ-3TR showed higher crystallinity lower miscibility than TDZ-3TR, enabling more driving force favor better fibrilization L8-BO. On other hand, two donor polymers PM6 D18 different widths lengths put together optimize layer. The simultaneously optimization layers resulted impressive power conversion efficiency (PCE) 19.38 % LbL-OSCs.

Language: Английский

---

Non-fullerene acceptors with high crystallinity and photoluminescence quantum yield enable >20% efficiency organic solar cells

Nature Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 29, 2025

Language: Английский

---

3D Crystal Framework Regulation Enables Se‐Functionalized Small Molecule Acceptors Achieve Over 19% Efficiency

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(19)

Published: March 10, 2024

Abstract Se‐functionalized small molecule acceptors (SMAs) exhibit unique advantages in constructing materials with near‐infrared absorption, but their photovoltaic performance lags behind that of S‐containing analogs organic solar cells (OSCs). Herein, two new Se‐containing SMAs, namely Se‐EH and Se‐EHp, are designed synthesized by regulating bifurcation site outer alkyl chain, which enables Se‐EHp to form different 3D crystal frameworks from CH1007. displays tighter π–π stacking denser packing framework smaller‐sized pore structure induced larger steric hindrance effect chain branched at 2‐position, a higher dielectric constant PM6:Se‐EH active layer can be obtained. OSCs based on achieved very high PCEs 18.58% binary 19.03% ternary devices FF approaching 80% for SMAs. A more significant adjusts the molecular crystallization favorable nanofiber interpenetrating network an appropriate domain size reduce rate sub‐ns recombination promote balanced transport carriers. This work provides references further design development highly efficient

Language: Английский

---

Ameliorated trap density and energetic disorder via a strengthened intermolecular interaction strategy to construct efficient non-halogenated organic solar cells

Energy & Environmental Science, Journal Year: 2024, Volume and Issue: 17(15), P. 5542 - 5551

Published: Jan. 1, 2024

The efficiency of non-halogenated organic solar cells is improved from 17.1% to 19.4% after dibenzyl ether (DBE) additive treatment. More strikingly, the thick-film devices achieved a champion 17.4%.

Language: Английский

---

Volatile Solid‐Assisted Molecular Assembly Enables Eco‐Friendly Processed Organic Photovoltaic Cells with High Efficiency and Photostability

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(17)

Published: Jan. 4, 2024

Achieving environmentally friendly solvent-processed high-performance organic photovoltaic cells (OPVs) is a crucial step toward their commercialization. Currently, OPVs with competitive efficiencies rely heavily on harmful halogenated solvent additives. Herein, the green and low-cost 9-fluorenone (9-FL) employed as solid additive. By using o-xylene/9-FL system, PM6:BTP-eC9-based devices deliver power-conversion of 18.6% 17.9% via spin-coating blade-coating respectively, outperforming all PM6:Y-series binary solvents. It found that addition 9-FL can regulate molecular assembly both PM6 BTP-eC9 in film-formation (molecule-level mixing) post-annealing (thermal-assisted reorganization additive volatilization) stages, so to optimize blend morphology. As result, charge transport ability donor acceptor phases are simultaneously enhanced, trap-assisted recombination reduced, which contributes higher short-circuit current density fill factor. Moreover, generation photo-induced traps significantly suppressed, resulting improved stability under illumination. further demonstrated excellent universality various photoactive systems, making it promising strategy advance development eco-friendly OPVs.

Language: Английский

---

C-Shape or S-Shape? The Molecular Geometry Control of Fused-Ring Nonfullerene Acceptors for Lower Energy Loss in Organic Solar Cells

ACS Energy Letters, Journal Year: 2024, Volume and Issue: 9(4), P. 1786 - 1795

Published: March 28, 2024

To elucidate the pivotal influence of molecular geometry in fused-ring nonfullerene acceptors (FRNFAs) on material properties and device performance organic solar cells (OSCs), we designed synthesized two isomeric molecules C–F S–F, featuring C-shaped S-shaped geometries with acceptor–donor–acceptor conjugated framework. The alteration demonstrated negligible effects optical electrochemical properties. Significantly, single crystal X-ray crystallography analyses uncovered that exhibited a wave network packing, while S–F favored linear brick packing intermolecular end groups, different from previously reported three-dimensional (3D) stacking Y series FRNFAs. Despite absence 3D OSCs utilizing remarkable power conversion efficiency 17.0%, lower voltage loss compared to devices based S–F. This study further underscores essential role FRNFAs, providing valuable insights for future design high-performance OSCs.

Language: Английский

---

Alcohol‐Soluble n‐Type Polythiophenes as Cathode Interlayer in Organic Photodetectors for Hole Blocking

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(24)

Published: Feb. 7, 2024

Abstract For organic photodetectors (OPDs), cathode interlayer (CIL) with low‐lying highest occupied molecular orbital ( E HOMO ) energy level is required to reduce dark current density J d ). In this study, toward application as CIL in OPDs, an alcohol‐processable n‐type conjugated polymer (n‐PT8) based on imide/cyano‐substituted polythiophene backbone and branched oligo(ethylene glycol) side chain developed. Owing the electron‐accepting imide/cyano groups backbone, n‐PT8 exhibits deep‐lying of −5.80 eV a high conductivity 5.12 × 10 −6 S cm −1 . OPD one order magnitude lower than that state‐of‐the‐art material because large barrier for reverse hole injection. Moreover, device performance insensitive layer thickness, which very desirable mass production OPDs. The near‐infrared (NIR) OPDs exhibit ultra‐low 1.76 −9 A −2 specific detectivity 2.88 12 Hz 1/2 W at V. To best knowledge, first report derivatives opto‐electronic devices.

Language: Английский

---

In‐Situ Removable Solid Additive Optimizing Active Layer and Cathode Interlayer of Organic Solar Cells

Advanced Energy Materials, Journal Year: 2024, Volume and Issue: 14(40)

Published: July 21, 2024

Abstract In situ removable (ISR) solid additive can employ cold sublimation process to optimize active layer morphology for organic solar cells (OSCs), thus remaining unique potential. Herein, a feasible guideline is proposed discover new ISR 1‐bromo‐4‐chlorobenzene (CBB), whose removing time ( T R ) between those of reported additives 1,4‐dichlorobenzene (DCB) and 1‐chloro‐4‐iodobenzene (CIB). The CBB with moderate beneficial affording the optimal achieving highest power conversion efficiency (PCE) 18.58% D18:L8‐BO binary layer, as supported by most efficient exciton splitting, fastest transfer, balanced carrier transports. Due ability, DCB, CBB, CIB are further aggregation PDINN cathode interlayer. Particularly, CBB‐ CIB‐treated interlayers afforded based OSCs excellent PCEs 19.38% 19.26%, along remarkable fill factors 80.98% 81.37%, respectively. suppress non‐radiative recombination devices, resulting in higher open‐circuit voltage. This work not only provides an effective approach flourish but also expands application OSCs.

Language: Английский

---