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While transfer‐printing is a great technique for efficient film fabrication of many emerging devices on various substrates, its application in organic solar cells (OSCs) is rarely explored. Besides, it is highly challenging to fabricate a large‐scale production of a "dual‐function OSC module" that runs two‐objective functions simultaneously in a given single system. Through comprehensive investigation on the transfer‐printing feasibility of various π‐conjugated organic materials, in addition to successful transfer‐printed OSC and flexible OSC module, implementation of dual‐function OSC modules via the transfer‐printing, in which two individual sub‐cell series based on dual‐purpose photoactive layers are separately integrated into a single system is showcased here. Moreover, the fabrication and operation of a wearable integrated self‐powered system for wireless healthcare monitoring with the wearable transfer‐printed dual‐function OSC module are also demonstrated. This study opens the door to fabricating OSCs with multi‐objective structures via the transfer‐printing technique, which enables the extra device‐level values for advanced energy‐related applications. [ABSTRACT FROM AUTHOR]

In the pursuit of high‐efficiency polythiophene (PT) organic solar cells (OSCs), a critical challenge is the reduction of nonradiative recombination. This study comprehensively explores polydithienylthiazolothiazole (PTTz)‐based PT terpolymers: PTTz‐Tz and PTTz‐TzT, in which it is demonstrate that molecular structure alterations greatly influence the aggregation kinetics and orientation of these polymers. Specifically, PTTz‐TzT achieves rapid ordering aggregation during spin coating, effectively suppressing excessive polymer aggregation and facilitating appropriate phase separation upon mixing with the acceptor. Meanwhile, PTTz‐TzT inherently adopts a face‐on orientation, resulting in more structured π–π stacking in the vertical direction after acceptor integration, compared to the intrinsic edge‐on orientation of PTTz‐Tz. These factors collectively contribute to lower Urbach energy and a substantial reduction of nonradiative recombination in PTTz‐TzT‐based OSCs, culminating in a high photovoltaic conversion efficiency (PCE) exceeding 16%. Furthermore, a prominent PCE of 19.11% is obtained by PTTz‐TzT via ternary blend strategy, which is among the highest values reported for the OSCs. This investigation underscores the significance of aggregation kinetics and orientation in PT‐based polymers, especially regarding Urbach energy and nonradiative recombination, and offers novel insights for designing high‐performance polythiophene donors. [ABSTRACT FROM AUTHOR]

Rotavirus considerably threatens global health, particularly for children <5 years. Current, licensed oral attenuated vaccine formulations have limitations including insufficient efficacy in children in low- and middle-income countries, warranting urgent development of novel vaccines with improved efficacy and safety profiles. Herein, we present a novel approach utilizing an encapsulin (ENC) nanoparticle (NP)-based non-replicating rotavirus vaccine. ENC, originating from bacteria, offers a self-assembling scaffold that displays rotavirus VP8* antigens on its surface. To enhance the correct folding and soluble expression of monomeric antigens and their subsequent assembly into NP, we adopted an RNA-interacting domain (RID) of mammalian transfer RNA synthetase as an expression tag fused to the N-terminus of the ENC-VP8* fusion protein. Using the RID-ENC-VP8* tripartite modular design, insertion of linkers of appropriate length and sequence and the universal T cell epitope P2 remarkably improved the production yield and immunogenicity. Cleavage of the RID rendered a homogenous assembly of ENC-P2-VP8* into protein NPs. Immunization with ENC-P2-VP8* induced markedly higher levels of VP8*-specific antibodies and virus neutralization titers in mice than those induced by P2-VP8* without ENC. Altogether, these results highlight the potential of the designed ENC NP-based rotavirus vaccine as an effective strategy against rotavirus disease to address global health challenges. [ABSTRACT FROM AUTHOR]

Ternary copolymerization is a cost‐effective and time‐saving approach to improve device performance and batch stability of polymer donors. However, the structure of the ternary polymer donor obtained by the traditional one‐pot polymerization is vague due to the different monomer reaction order, which has a great influence on the absorption, crystallization, molecular stacking, and device performance. Therefore, it is necessary to obtain terpolymers with definite structures, and systematically study the differences in device properties of polymers with different sequence structures. Herein, three terpolymers D1, D2, and D3 are developed. Random copolymer D3 is obtained via the traditional one‐pot method while alternating copolymer donor D1 and block copolymer D2 are synthesized by stepwise polymerization. Because the block copolymer D2 possess periodic sequence distribution and retains the excellent properties of the two polymer matrix very well, the D2‐based device shows enhanced tightened π‐face‐on molecular stacking, distinguished efficient exciton dissociation, and decreased energy loss. As a result, the D2:L8‐BO‐based polymer solar cells achieve one of a record power conversion efficiency of 19.03%. The work demonstrates changing the sequence structure of the polymers to synthesize well‐defined structures polymer donors not only maintains the features of polymer matrix, but also combines the advantages of ternary copolymerization. [ABSTRACT FROM AUTHOR]

Ternary polymerization are demonstrated as a feasible and successful method of optimizing absorption, energy level, and crystallinity by maintaining the excellent properties of a polymer matrix. However, the third unit inevitably interrupts the periodic sequence distribution of the ordering packing of conjugated backbones, and thus balancing the trade‐off between the advantages of the third component and the disruption caused by the nonperiodic sequence distribution remains a great challenge. Herein, two terpolymer donors L1 and L2 are developed by introducing diethyl‐5,5′"‐dibromo‐4,4′"‐bis(2‐ethylhexyl)‐[2,2′:5′,2′'‐terthiophene]‐3′,4′‐dicarboxylate (DDT) unit as the third component. Owing to the electron‐deficient ability and S···O non‐covalent intramolecular interactions of DDT, terpolymers L1 and L2 displays deeper energy levels, enhanced molecular rigidity, and planarity than PM6. After blending with L8‐BO, the L1‐based polymer solar cells exhibit well miscibility with L8‐BO, leading to a more well‐defined nanofibrous morphology, face‐on orientation, and a slight energy loss in the blend films. As a result, the optimized L1:L8‐BO‐based device achieves a record power conversion efficiency (PCE) as high as 18.75%. This work provides a feasible strategy to develop high‐performance polymer donors via utilizing S···O non‐covalent intramolecular interactions to improve the planarity of polymer donors. [ABSTRACT FROM AUTHOR]

A detailed investigation addressing the effects of functionalizing conjugated polymers with oligo(ethylene glycol) (EGn) sidechains on the performance and polymer‐electrolyte compatibility of electrochromic devices (ECDs) is reported. The electrochemistry for a series of donor‐acceptor copolymers having near‐infrared (NIR)‐optical absorption, where the donor fragment is 3,4‐ethylenedioxythiophene (EDOT) or an EGn functionalized bithiophene (g2T) and the acceptor fragment is diketopyrrolopyrrole (DPP) functionalized with branched alkyl or EGn sidechains, is extensively probed. ECDs are next fabricated and it is found that EGn sidechain incorporation must be finely balanced to promote polymer‐electrolyte compatibility and provide efficient ion exchange. Proper electrolyte‐cation pairing and polymer structural tuning affords a 2x increase in optical contrast (from 12% to 24%) and >60x reduction in switching time (from 20 to 0.3 s). Atomic force microscopy (AFM)/grazing incidence wide‐angle X‐ray scattering (GIWAXS) characterization of the polymer film morphology/microstructure reveals that an over‐abundance of EGn sidechains generates large polymer crystallites, which can suppress ion exchange. Lastly, time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) indicates sidechain/electrolyte identity does not influence the electrolyte penetration depth into the films, and EGn sidechain inclusion increases electrolyte cation uptake. The material structural design insight and guidelines regarding the polymer‐electrolyte ion insertion/expulsion dynamics reported here should be of significant utility for developing next‐generation mixed ionic‐electronic conducting materials. [ABSTRACT FROM AUTHOR]

Volatile solid additives are an effective strategy for optimizing morphology and improving the power conversion efficiencies (PCEs) of organic solar cells (OSCs). Much research has been conducted to understand the role of solid additives in active layer morphology. However, it is crucial to delve deeper and understand how solid additives affect the entire morphology evolution process, from the solution state to the film state and the thermal annealing stage, which remains unclear. Herein, the use of a highly crystalline solid additive, phenoxathiin (Ph), in D18‐Cl:N3‐based OSCs and study its impact on morphology formation and photovoltaic performance is presented. Owing to its good miscibility with the acceptor N3, Ph additive can not only extend the time for the active layer to form from the solution state to the film state, but also provide sufficient time for acceptor aggregation. After thermal annealing, Ph solid additive volatilizes better aligned the N3 molecules and formed a favorable hybrid morphology. Consequently, the D18‐Cl:N3–based OSC exhibited an outstanding PCE of 18.47%, with an enhanced short‐circuit current of 27.50 mA cm−2 and a fill factor of 77.82%. This research is spurring the development of high‐performance OSCs using solid additives that allow fine control during morphology development. [ABSTRACT FROM AUTHOR]

A thermal annealing-free solid additive octafluoronaphthalene was developed for high-performance organic solar cells. In an additive-modified device, an impressive power conversion efficiency of 18.59% from 17.27% was achieved with simultaneously enhanced current density from 26.86 to 27.53 mA cm−2 and fill factor from 74.34% to 78.85%. [ABSTRACT FROM AUTHOR]