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Iodination has unlocked new potentials in organic photovoltaics (OPVs). A newly designed and synthesized iodinated non‐fullerene acceptor, BO‐4I, showcases exceptional excitation delocalization property with the exciton diffusion length increased to 80 nm. The enhanced electron delocalization property is attributed to the larger atomic radius and electron orbit of the iodine atom, which facilitates the formation of intra‐moiety excitations in the acceptor phase. This effectively circumvents the charge transfer state‐related recombination mechanisms, leading to a substantial reduction in non‐radiative energy loss (ΔEnr). As a result, OPV cell based on PBDB‐TF : BO‐4I achieves an impressive efficiency of 18.9 % with a notable ΔEnr of 0.189 eV, markedly surpassing their fluorinated counterparts. This contribution highlights the pivotal role of iodination in reducing energy loss, thereby affirming its potential as a key strategy in the development of advanced next‐generation OPV cells. [ABSTRACT FROM AUTHOR]

Innovative molecule design strategy holds promise for the development of next‐generation acceptor materials for efficient organic solar cells with low non‐radiative energy loss (ΔEnr). In this study, we designed and prepared three novel acceptors, namely BTP‐Biso, BTP‐Bme and BTP‐B, with sterically structured triisopropylbenzene, trimethylbenzene and benzene as side chains inserted into the shoulder of the central core. The progressively enlarged steric hindrance from BTP‐B to BTP‐Bme and BTP‐Biso induces suppressed intramolecular rotation and altered the molecule packing mode in their aggregation states, leading to significant changes in absorption spectra and energy levels. By regulating the intermolecular π–π interactions, BTP‐Bme possesses relatively reduced non‐radiative recombination rate and extended exciton diffusion lengths. The binary device based on PB2 : BTP‐Bme exhibits an impressive power conversion efficiency (PCE) of 18.5 % with a low ΔEnr of 0.19 eV. Furthermore, the ternary device comprising PB2 : PBDB‐TF : BTP‐Bme achieves an outstanding PCE of 19.3 %. The molecule design strategy in this study proposed new perspectives for developing high‐performance acceptors with low ΔEnr in OSCs. [ABSTRACT FROM AUTHOR]

To meet the industrial requirements of organic photovoltaic (OPV) cells, it is imperative to accelerate the development of cost‐effective materials. Thiophene‐benzene‐thiophene central unit‐based acceptors possess the advantage of low synthetic cost, while their power conversion efficiency (PCE) is relatively low. Here, by incorporating a para‐substituted benzene unit and 1st‐position branched alkoxy chains with large steric hindrance, a completely non‐fused non‐fullerene acceptor, TBT‐26, was designed and synthesized. The narrow band gap of 1.38 eV ensures the effective utilization of sunlight. The favorable phase separation morphology of TBT‐26‐based blend film facilitates the efficient exciton dissociation and charge transport in corresponding OPV cell. Therefore, the TBT‐26‐based small‐area cell achieves an impressive PCE of 17.0 %, which is the highest value of completely non‐fused OPV cells. Additionally, we successfully demonstrated the scalability of this design by fabricating a 28.8 cm2 module with a high PCE of 14.3 %. Overall, our work provides a practical molecular design strategy for developing high‐performance and low‐cost acceptors, paving the way for industrial applications of OPV technology. [ABSTRACT FROM AUTHOR]

In the field of organic photovoltaics (OPVs), significant progress has been made in tailoring molecular structures to enhance the open‐circuit voltage and the short‐circuit current density. However, there remains a crucial gap in the development of coordinated material design strategies focused on improving the fill factor (FF). Here, we introduce a molecular design strategy that incorporates electrostatic potential fluctuation to design organic photovoltaic materials. By reducing the fluctuation amplitude of IT‐4F, we synthesized a new acceptor named ITOC6‐4F. When using PBQx‐TF as a donor, the ITOC6‐4F‐based cell shows a markedly low recombination rate constant of 0.66×10−14 cm3 s−1 and demonstrates an outstanding FF of 0.816, both of which are new records for binary OPV cells. Also, we find that a small fluctuation amplitude could decrease the energetic disorder of OPV cells, reducing energy loss. Finally, the ITOC6‐4F‐based cell creates the highest efficiency of 16.0 % among medium‐gap OPV cells. Our work holds a vital implication for guiding the design of high‐performance OPV materials. [ABSTRACT FROM AUTHOR]

Organic solar cells (OSCs) are still suffering from the low light utilization and unstable under ultraviolet irradiation. To tackle these challenges, we design and synthesize a non‐fused acceptor based on 1‐(2‐butyloctyl)‐1H‐pyrrole as π‐bridge unit, denoted as GS70, which serves as active layer in the front‐cell for constructing tandem OSCs with a parallel configuration. Benefiting from the well‐complementary absorption spectra with the rear‐cell, GS70‐based parallel tandem OSCs exhibit an improved photoelectron response over the range between 600–700 nm, yielding a high short‐circuit current density of 28.4 mA cm−2. The improvement in light utilization translates to a power conversion efficiency of 19.4 %, the highest value among all parallel tandem OSCs. Notably, owing to the intrinsic stability of GS70, the manufactured parallel tandem OSCs retain 84.9 % of their initial PCE after continuous illumination for 1000 hours. Overall, this work offers novel insight into the molecular design of low‐cost and stability non‐fused acceptors, emphasizing the importance of adopting a parallel tandem configuration for achieving efficient light harvesting and improved photostability in OSCs. [ABSTRACT FROM AUTHOR]

Organic photovoltaic (OPV) cells, with highly tunable light‐response ranges, offer significant potential for use in driving low‐power consumption off‐grid electronics in multi‐scenarios. However, development of photoactive layer materials that can meet simultaneously the requirements of diverse irradiation conditions is a still challenging task. Herein, a low‐cost fully non‐fused acceptor (denoted as GS60) featuring well‐matched absorption spectra with solar, scattered light and artificial light radiation was designed and synthesized. Systematic characterizations revealed that GS60 possessed outstanding photoelectron properties and ideal morphology, which resulted in reduced voltage loss and suppressed charge recombination. By blending with a non‐fused ring polymer PTVT−T, the as‐obtained GS60 based OPV cells achieved a good power conversion efficiency (PCE) of 14.1 %, a high value for the cells based on non‐fused ring bulk heterojunction. Besides, manufactured large‐area OPV modules based on PTVT−T:GS60 yielded PCEs of 11.2 %, 11.8 %, 12.1 %, 23.1 %, and 20.3 % under irradiation of AM 1.5G, natural light of cloudy weather, natural light in shadow, laser and indoor, respectively. The PTVT−T:GS60 devices exhibited considerable potential in terms of improving photostability and reducing material cost. Overall, this work provides novel insight into the molecular design of low‐cost non‐fused ring acceptors, and extended potential of medium band gap acceptors based OPV cells used in various application scenarios. [ABSTRACT FROM AUTHOR]

Potassium–sulfur (K−S) batteries have attracted wide attention owing to their high theoretical energy density and low cost. However, the intractable shuttle effect of K polysulfides results in poor cyclability of K−S batteries, which severely limits their practical application. Herein, a bifunctional concentrated electrolyte (3 mol L−1 potassium bis(trifluoromethanesulfonyl)imide in ethylene carbonate (EC)) with high ionic conductivity and low viscosity is developed to regulate the dissolution behavior of polysulfides and induce uniform K deposition. The organic groups in the cathode electrolyte interphase layer derived from EC can effectively block the polysulfide shuttle and realize a "solid–liquid–solid" reaction mechanism. The KF‐riched solid‐electrolyte interphase inhibits K dendrite growth during cycling. As a result, the achieved K−S batteries display a high reversible capacity of 654 mAh g−1 at 0.5 A g−1 after 800 cycles and a long lifespan over 2000 cycles at 1 A g−1. [ABSTRACT FROM AUTHOR]

To modulate the miscibility between donor and acceptor materials both possessing fully non‐fused ring structures, a series of electron acceptors (A4T‐16, A4T‐31 and A4T‐32) with different polar functional substituents were synthesized and investigated. The three acceptors show good planarity, high conformational stability, complementary absorption and energy levels with the non‐fused polymer donor (PTVT‐BT). Among them, A4T‐32 possesses the strongest polar functional group and shows the highest surface energy, which facilitates morphological modulation in the bulk heterojunction (BHJ) blend. Benefiting from the proper morphology control method, an impressive power conversion efficiency (PCE) of approaching 16.0 % and a superior fill factor over 0.795 are achieved in the PTVT‐BT : A4T‐32‐based organic photovoltaic cells with superior photoactive materials price advantage, which represent the highest value for the cells based on the non‐fused blend films. Notably, this cell maintains ≈84 % of its initial PCE after nearly 2000 h under the continuous simulated 1‐sun‐illumination. In addition, the flexible PTVT‐BT : A4T‐32‐based cells were fabricated and delivered a decent PCE of 14.6 %. This work provides an effective molecular design strategy for the non‐fused non‐fullerene acceptors (NFAs) from the aspect of bulk morphology control in fully non‐fused BHJ layers, which is crucial for their practical applications. [ABSTRACT FROM AUTHOR]