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As simple and versatile tools, additives have been widely used to refine active layer morphology and have played a crucial role in boosting the power conversion efficiency (PCE) of organic solar cells (OSCs). Herein, three novel solvent additives named Th‐FSi, Th‐ClSi, and Th‐BrSi with the same backbone of 2,5‐bis(trimethylsilyl)thiophene are designed and synthesized by substituting different halogens of fluorine, chlorine, and bromine, respectively. Notably, Th‐ClSi exhibits the more significant dipole moment and engages in non‐covalent interactions with a small‐molecule acceptor (SMA) L8‐BO, which slight adjustments in intermolecular interaction, crystallinity, and molecular packing in the PM6:L8‐BO active layer. Consequently, the OSCs incorporating Th‐ClSi outperform their Th‐FSi and Th‐BrSi counterparts in photo‐capturing, reduced energy loss, superior exciton dissociation, and charge transfer properties, out‐coming yields in an enhanced PCE of 18.29%. Moreover, by integrating a near‐infrared absorbing SMA (BTP‐eC9) guest into the PM6:L8‐BO matrix, the absorption spectrum to span 880–930 nm, and the resultant ternary OSCs achieve a commendable PCE of 19.17%, ranking among the highest efficiencies reported to date is expanded. These findings underscore the promise of halogenated thiophene‐based solvent additives as a potent avenue for morphological fine‐tuning and consequent PCE enhancement in OSCs. [ABSTRACT FROM AUTHOR]

To simultaneously stabilize cesium lead triiodide (CsPbI3) precursor solution and passivate the defects in CsPbI3 film is greatly significant for achieving highly stable and efficient CsPbI3 perovskite solar cells (PSCs). Herein, an effective redox 4‐fluorobenzothiohydrazide (FBTH) is developed to stabilize the precursor solution and passivate iodine/lead‐related defects for high‐quality CsPbI3 film. The comprehensive research confirms that 1) a new compound FBTH‐I is obtained from an effective redox interaction between FBTH and molecular iodine (I2) in perovskite precursor solution, which can effectively impede the formation of I2 molecule and restrain I− migration in perovskite film by forming N–H···I bond; 2) FBTH‐I can also passivate Pb‐related defects via forming S···Pb interaction. Consequently, the CsPbI3 PSC based on FBTH‐treated precursor solution exhibits a fascinating power conversion efficiency (PCE) of 21.41%, which is one of the highest PCE values among the reported pure CsPbI3 PSCs so far, and an outstanding stability against the harsh conditions, such as thermal annealing and continuous light‐illumination. [ABSTRACT FROM AUTHOR]

The passivation effect of inorganic perovskite quantum dots (PQDs) is a promising method to attain outstanding performance in perovskite solar cells (PSCs), which has ignited widespread interest recently. Lanthanides (Ln) doped PQDs demonstrate unique properties, but nevertheless, are not explored in PSCs. In this work, four kinds of Ln3+ doped CsPbBrCl2 PQDs (Ln3+ = Yb3+, Ce3+, Eu3+, Sm3+) are firstly introduced into PSCs, which displays the synergistic effect of composition engineering and defect engineering. The results indicate that the introduction of CsPbBrCl2: Ln3+ can not only improve the crystallinity and passivate the intrinsic and surface defects of the MAPbI3 layer through ion and ligand passivation, but also form a stronger LnI bond than PbI, adjust work function (WF), and optimize band alignments. CsPbBrCl2:Sm3+ PQDs possess the best performance and exhibit remarkable promotions of open‐circuit voltage (Voc) from 1.13 to 1.20 V and power conversion efficiency from 18.54% to 22.52%. The humid‐resist, thermal‐resist abilities, and the long‐term stability of PSCs are energetically improved due to enhanced structure stability by Sm3+ doping and the hydrophobic characteristic. The strategy of Ln3+ doped PQDs applied to PSCs provide an approach to achieve high‐performance PSCs. [ABSTRACT FROM AUTHOR]

Herein, asymmetric isomer effects are systematically explored by designing and synthesizing two benzo[c][1,2,5]thiadiazole (BT)‐fused nonacyclic electron acceptors. By changing from BP6T‐4F to asymmetric ABP6T‐4F, significantly enhanced dielectric constant and inhibited excessive molecular aggregation and unfavorable edge‐on orientation could be achieved. The reduced exciton binding energy also facilitates a more efficient dissociation process in PM6:ABP6T‐4F compared to PM6:BP6T‐4F with the same energy offset. Moreover, the weaker crystallization behavior enables a significantly enhanced miscibility between PM6 and ABP6T‐4F than that between PM6 and BP6T‐4F, which leads to an optimized micromorphology with smooth surface, suitable domain size, and ordered π–π stacking. Organic solar cells (OSCs) based on PM6:ABP6T‐4F achieve a 15.8% power conversion efficiency (PCE), which is remarkably higher than that of PM6:BP6T‐4F‐based OSCs (6.4%). Furthermore, ternary devices are also fabricated considering good compatibility between ABP6T‐4F and CH1007 to deliver a PCE over 17%. This study reveals the effectiveness and great potential of asymmetric isomerization strategy in regulating molecular properties, which will provide guidance for the future design of non‐fullerene acceptors. [ABSTRACT FROM AUTHOR]

Metal halide perovskite quantum dots (QDs) have garnered tremendous attention in optoelectronic devices owing to their excellent optical and electrical properties. However, these perovskite QDs are plagued by pressure‐induced photoluminescence (PL) quenching, which greatly restricts their potential applications. Herein, the unique optical and electrical properties of Eu3+‐doped CsPbCl3 QDs under high pressure are reported. Intriguingly, the PL of Eu3+ ions displays an enhancement with pressure up to 10.1 GPa and still preserves a relatively high intensity at 22 GPa. The optical and structural analysis indicates that the sample experiences an isostructural phase transition at approximately 1.53 GPa, followed by an amorphous state evolution, which is simulated and confirmed through density functional theory calculations. The pressure‐induced PL enhancement of Eu3+ ions can be associated with the enhanced energy transfer rate from excitonic state to Eu3+ ions. The photoelectric performance is enhanced by compression and can be preserved upon the release of pressure, which is attributed to the decreased defect density and increased carrier mobility induced by the high pressure. This work enriches the understanding of the high‐pressure behavior of rare‐earth‐doped luminescent materials and proves that high pressure technique is a promising way to design and realize superior optoelectronic materials. [ABSTRACT FROM AUTHOR]

Botanical systems have evolved the intriguing ability to respond to diverse stimuli due to long‐term survival competition. Mimicking these dynamic behaviors has greatly advanced the developments in wide fields ranging from soft robotics, precision sensors to drug delivery and biomedical devices. However, realization of stimuli‐responsive components at the microscale with high response speed still remains a significant challenge. Herein, the miniature biomimetic 4D printing of pH‐responsive hydrogel is reported in spatiotemporal domain by femtosecond laser direct writing. The dimension of the printed architectures is at the microscale (<102 µm) and the response speed is reduced down to subsecond level (<500 ms). Shape transformation with multiple degrees of freedom is accomplished by taking advantage of pH‐triggered expansion, contraction, and torsion. Biomimetic complex shape‐morphing is enabled by adopting flexible scanning strategies. In addition, application of this 4D‐printed micro‐architecture in selective micro‐object trapping and releasing is demonstrated, showcasing its possibilities in micromanipulation, single‐cell analysis, and drug delivery. [ABSTRACT FROM AUTHOR]