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Molecular passivation is a prominent approach for improving the performance and operation stability of halide perovskite solar cells (HPSCs). Herein, we reveal discernible effects of diammonium molecules with either an aryl or alkyl core onto Methylammonium-free perovskites. Piperazine dihydriodide (PZDI), characterized by an alkyl core-electron cloud-rich-NH terminal, proves effective in mitigating surface and bulk defects and modifying surface chemistry or interfacial energy band, ultimately leading to improved carrier extraction. Benefiting from superior PZDI passivation, the device achieves an impressive efficiency of 23.17% (area ~1 cm 2 ) (low open circuit voltage deficit ~0.327 V) along with superior operational stability. We achieve a certified efficiency of ~21.47% (area ~1.024 cm 2 ) for inverted HPSC. PZDI strengthens adhesion to the perovskite via -NH 2 I and Mulliken charge distribution. Device analysis corroborates that stronger bonding interaction attenuates the defect densities and suppresses ion migration. This work underscores the crucial role of bifunctional molecules with stronger surface adsorption in defect mitigation, setting the stage for the design of charge-regulated molecular passivation to enhance the performance and stability of HPSC. Molecular passivation is promising for improving the performance and operation stability of perovskite solar cells. Here, authors employ piperazine dihydriodide to strengthen adhesion to MA-free perovskite via −NH 2 I and Mulliken charge distribution, realizing charge-regulated molecular passivation.

HighlightsA comprehensive review is presented on the chemical reactions of perovskite films under different environmental conditions and with charge transfer materials and metal electrodes in perovskite solar cells.The influence of chemical reactions on device stability is elucidated. Effective strategies for suppressing the degradation reactions are specified. Lead halide perovskite solar cells (PSCs) have become a promising next-generation photovoltaic technology due to their skyrocketed power conversion efficiency. However, the device stability issues may restrict their commercial applications, which are dominated by various chemical reactions of perovskite layers. Hence, a comprehensive illustration on the stability of perovskite films in PSCs is urgently needed. In this review article, chemical reactions of perovskite films under different environmental conditions (e.g., moisture, oxygen, light) and with charge transfer materials and metal electrodes are systematically elucidated. Effective strategies for suppressing the degradation reactions of perovskites, such as buffer layer introduction and additives engineering, are specified. Finally, conclusions and outlooks for this field are proposed. The comprehensive review will provide a guideline on the material engineering and device design for PSCs.

Additives play a crucial role in enhancing the photovoltaic performance of polymer solar cells (PSCs). However, the typical additives used to optimize blend morphology of PSCs are still high boiling-point solvents, while their trace residues may reduce device stability. Herein, an effective strategy of “solidification of solvent additive (SSA)” has been developed to convert additive from liquid to solid, by introducing a covalent bond into low-cost solvent diphenyl sulfide (DPS) to synthesize solid dibenzothiophene (DBT) in one-step, which achieves optimized morphology thus promoting efficiency and device stability. Owing to the fine planarity and volatilization of DBT, the DBT-processed films achieve ordered molecular crystallinity and suitable phase separation compared to the additive-free or DPS-treated ones. Importantly, the DBT-processed device also possesses improved light absorption, enhanced charge transport, and thus a champion efficiency of 17.9% is achieved in the PM6:Y6-based PSCs with an excellent additive component tolerance, reproducibility, and stability. Additionally, the DBT-processed PM6:L8-BO-based PSCs are further fabricated to study the universality of SSA strategy, offering an impressive efficiency approaching 19% as one of the highest values in binary PSCs. In conclusion, this article developed a promising strategy named SSA to boost efficiency and improve stability of PSCs.

HighlightsQuantum dots light emitting devices (QLEDs) with extremely long half-lifetimes at 100 cd m−2, 2,370,000 h were successfully fabricated using CF4 plasma-treated ZnO nanoparticle electron transport layers.A new experimental approach that probes changes in exciton lifetime under current flow was used to investigate the changes in carrier concentration in QLEDs.Evidence of the dependence of QLED stability on electron and hole concentrations at the QD/HTL interface was revealed.ZnO nanoparticles are widely used for the electron transport layers (ETLs) of quantum dots light emitting devices (QLEDs). In this work we show that incorporating fluorine (F) into the ZnO ETL results in significant enhancement in device electroluminescence stability, leading to LT50 at 100 cd m−2 of 2,370,000 h in red QLED, 47X longer than the control devices. X-ray photo-electron spectroscopy, time-of-flight secondary ion mass spectroscopy, photoluminescence and electrical measurements show that the F passivates oxygen vacancies and reduces electron traps in ZnO. Transient photoluminescence versus bias measurements and capacitance–voltage-luminance measurements reveal that the CF4 plasma-treated ETLs lead to increased electron concentration in the QD and the QD/hole transport layer interface, subsequently decreasing hole accumulation, and hence the higher stability. The findings provide new insights into the critical roles that optimizing charge distribution across the layers play in influencing stability and present a novel and simple approach for extending QLED lifetimes.

Interfacial regulation, serving multiple roles, is critical for the fabrication of stable and efficient organic photovoltaics (OPVs). Herein, a multifunctional cathode interlayer PDINO (15 nm) is prepared by regulating film thickness, which is inserted between active components and stable silver electrode to align work function, and maintain good interfacial contact and device stability. The thick film can help to reduce interfacial surface defects, keep stable surface morphology, and block the silver diffusion into the active layer. Consequently, the optimal PM6:Y6 device records an impressive power conversion efficiency (PCE) of 17.48% with minimized non-radiative recombination loss of 0.239 V. More importantly, the unencapsulated device maintains 91% of the original PCE after aging for over 60 days at 25 °C and 10% relative humidity in dark conditions. Meanwhile, the PM6:eC9 device achieves a remarkable PCE of 18.22% with the enhancement of open-circuit voltage ( V oc ). Furthermore, the 1 cm 2 device-based PDINO (15 nm)/Ag shows a high PCE of 15.2% while only 12.6% for PDINO (9 nm)/Al, indicating the good compatibility of PDINO (15 nm) interlayer with the R2R coating processes used in large-area OPVs fabrication. This work highlights the promise of interfacial regulation to simultaneously stabilize and enhance the efficiency of organic photovoltaics.

Blue phosphorescent organic light-emitting diodes (B-PHOLEDs) using host–guest emissive layers have been studied, where the host and guest are 2,6-bis(3-(9H-carbazol-9-yl)phenyl)pyridine (26DCzPPy) and bis[2-(4,6-difluorophenyl)pyridinato-C 2 , N ](picolinato)iridium(III) (FIrPic), respectively. For the emissive layer with dye (guest) concentration of either 3 mol% or 10 mol%, there exist both the major and minor effective bandgaps. The major effective bandgap is governed by the lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) levels of 26DCzPPy, because the host molecules form a major dynamic-favorable channel to transport charge carriers. The minor effective bandgap is governed by the LUMO and HOMO levels of FIrPic, since the guest molecules form a minor thermodynamic-favorable channel to transport charge carriers. For the emissive layer with dye concentration of 22 mol%, the effective bandgap is determined by the LUMO and HOMO levels of FIrPic, because the guest molecules form a both dynamic- and thermodynamic-favorable channel to conduct charge carriers. Although the B-PHOLED with emissive layer of 26DCzPPy:FIrPic (3 mol%) shows wider exciton formation zone than the one with emissive layer of 26DCzPPy:FIrPic (10 mol%), the latter gives higher stability than the former, mostly attributed to the shorter triplet lifetime of 26DCzPPy:FIrPic (10 mol%) than that of 26DCzPPy:FIrPic (3 mol%). Due to both the larger effective bandgap and more charge carrier traps, the emissive layer of 26DCzPPy:FIrPic (10 mol%) enlarges the exciton formation zone and thereby increases device stability than that of 26DCzPPy:FIrPic (22 mol%), despite that the former has the longer triplet lifetime than the latter. The current research provides some novel insights into the correlation of dye-based nanoarchitectonics (dye concentration) with the device performance, helpful for the commercial development of B-PHOLEDs using host–guest emissive layers.

High‐performance perovskite solar cells (PSCs) depend heavily on the quality of perovskite films, which is closely related to the lattice distortion, perovskite crystallization, and interfacial defects when being spin‐coated and annealed on the substrate surface. Here, a dynamic strategy to modulate the perovskite film formation by using a soft perovskite–substrate interface constructed by employing amphiphilic soft molecules (ASMs) with long alkyl chains and Lewis base groups is proposed. The hydrophobic alkyl chains of ASMs interacted with poly(triarylamine) (PTAA) greatly improve the wettability of PTAA to facilitate the nucleation and growth of perovskite crystals, while the Lewis base groups bound to perovskite lattices significantly passivate the defects in situ. More importantly, this soft perovskite–substrate interface with ASMs between PTAA and perovskite film can dynamically match the lattice distortion with reduced interfacial residual strain upon perovskite crystallization and thermal annealing owing to the soft self‐adaptive long‐chains, leading to high‐quality perovskite films. Thus, the inverted PSCs show a power conversion efficiency approaching 20% with good reproducibility and negligible hysteresis. More impressively, the unencapsulated device exhibits state‐of‐the‐art photostability, retaining 84% of its initial efficiency under continuous simulated 1‐sun illumination for more than 6200 h at elevated temperature (≈65 °C). A dynamic modulation strategy is developed to fabricate high‐quality perovskite films by constructing soft perovskite‐substrate interfaces. As a result, the unencapsulated device shows state‐of‐the‐art photostability, maintaining 84% initial efficiency under continuous simulated 1‐sun illumination for more than 6200 h.

This study introduces novel phenothiazine-based organic dyes, 2-LBH-100, 2-LBH-44, and 2-Ryu-4, specifically designed for quasi-solid-state dye-sensitized solar cells (QsDSSCs). Employing a donor-π-acceptor architecture, these dyes incorporate varying electron-donating moieties, including bis(3-(hexyloxy)phenyl)amine and diphenylamino, coupled with a cyanoacrylic acid acceptor. Alkoxy substitutions in 2-LBH-100 and 2-LBH-44 enhanced solubility and dye loading on TiO2, leading to improved performance in QsDSSCs. 2-LBH-100 exhibited a power conversion efficiency (PCE) exceeding 5% with excellent stability, while 2-LBH-44 demonstrated a PCE of over 3%, increasing to 4% over time. 2-Ryu-4, with its diphenylamino donor, achieved an initial PCE of over 6%. This research highlights the crucial role of donor–acceptor interactions in optimizing organic dye design for high-performance QsDSSCs, paving the way for efficient and stable next-generation solar energy technologies.

The morphology of organic films plays a pivotal role in determining the performance of transistor devices. While the dip-coating technique is capable of producing highly oriented organic films, it often encounters challenges such as limited coverage and the presence of defects in gaps between strips, adversely affecting device performance. In this study, we address these challenges by increasing solution viscosity through the incorporation of a substantial proportion of dielectric polymers, thereby enhancing the participation of additional molecules during the film formation process when pulled up. This method produces continuous and oriented organic films with a notable absence of gaps, significantly improving the carrier mobility of transistor devices by more than twofold. Importantly, the fabricated devices exhibit remarkable reliability, showing no hysteresis even after 200 cycles of measurement. Furthermore, the current and threshold voltages of the devices demonstrate exceptional stability, maintaining steady after 10,000 s of bias measurement. This approach provides a solution for the cost-effective and large-scale production of organic transistors, contributing significantly to the advancement of organic electronics.

Morphology of the donor:acceptor blend plays a critical role in the photovoltaic performance of the organic solar cells (OSCs). Herein, liquid-phase-exfoliated black phosphorus nanoflakes (BPNFs), for their outstanding electronic property and good compatibility to solution process, were applied to fullerene-free OSCs as morphology modifier. Revealed by X-ray scattering measurements, the PTB7-Th:IEICO-4F blends incorporated with BPNFs exhibit more ordered π-π stacking and promoted domain purity, contributing to lower charge transport resistance and suppressed charge recombination within the bulk heterojunction (BHJ). As a result, a high fill factor (FF) of 0.73 and a best power conversion efficiency (PCE) of 12.2% were obtained for fullerene-free OSCs based on PTB7-Th:IEICO-4F blends incorporating with BPNFs, which is among the highest FF of the as-cast fullerene-free OSCs with PCE over 12%. More importantly, the embedded BPNFs help to improve the morphological stability of the devices probably by retarding the phase mixing in the BHJ during the aging period. Besides, analogous enhancements were observed in another fullerene-free OSCs based on PBDB-T:ITIC. In a word, this work provides a new strategy of using two-dimentional nanoflakes as facile and universal morphology modifier for efficient fullerene-free OSCs.