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Zinc (Zn) emerges as an ideal anode for aqueous‐based energy storage devices because of its safety, non‐toxicity, and cost‐effectiveness. However, the reversibility of zinc anodes is constrained by unchecked dendrite proliferation and parasitic side reactions. To minimize these adverse effects, a highly oriented, crystalline 2D porous fluorinated covalent organic framework (denoted as TpBD‐2F) thin film is in situ synthesized on the Zn anode as a protective layer. The zincophilic and hydrophobic TpBD‐2F provides numerous 1D fluorinated nanochannels, which facilitate the hopping/transfer of Zn2+ and repel H2O infiltration, thus regulating Zn2+ flux and inhibiting interfacial corrosion. The resulting TpBD‐2F protective film enabled stable plating/stripping in symmetric cells for over 1200 h at 2 mA cm−2. Furthermore, assembled full cells (Zn‐ion capacitors) deliver an ultra‐long cycling life of over 100 000 cycles at a current density of 5 A g−1, outperforming nearly all reported porous crystalline materials. [ABSTRACT FROM AUTHOR]

Highly sensitive and humidity‐resistive detection of the most common physical stimuli is of primary importance for practical application in real‐time monitoring. Here, a simple yet effective strategy is reported to achieve a highly humidity‐stable hybrid composite that enables simultaneous and accurate pressure and temperature sensing in a single sensor. The improved electronic performance is due to the enhanced planarity of poly (3,‐4ethylenedioxythiophene) (PEDOT) and charge transfer between PEDOT:polystyrene sulfonate (PEDOT:PSS) and multi‐walled carbon nanotubes (CNTs) by strong π–π interaction. The preferred electronic pathway induced by a robust morphology in the hybrid composite is responsible for the high humidity stability. This study also demonstrates that the sensor has tremendous potential for intelligent object identification with a high level of 97.78% accuracy. Together with the position‐detection capability of a triboelectric nanogenerator (TENG), advantages for potential industrial applications of the triple sensing system in terms of intelligent classification without seeing are foreseen. [ABSTRACT FROM AUTHOR]

Ubiquitous moisture in synthetic conditions and ambient environments can strongly influence the conductivity of ZnO semiconductors via the chemisorption and physisorption of water molecules on the ZnO surface. Such an intrinsically water‐sensitive nature will become more evident in mesoporous ZnO films where a large surface area and active sites are created simultaneously. However, fundamental insights underlying water‐mediated ZnO surface chemistry and electrical conductivity and the factors affecting them remain ambiguous due to the complexity of ZnO surfaces and the difficulties of in situ characterizations at multi‐dimensions. Here, self‐assembling diblock copolymers are exploited as structure‐directing agents to achieve mesoporous ZnO thin films with highly tailorable structural characteristics ranging from nanomorphologies, over crystalline levels, to defect contents. As verified by theoretical calculations, the presence of oxygen vacancy will facilitate favorable water adsorption and subsequent dissociation on the polar ZnO surfaces. Upon humidity exposure with progressively increased levels, mesoporous ZnO films are revealed to follow an almost positive relationship between adsorption and electrical conductivity but show superior morphological stability. This work not only elucidates the water‐governed ZnO surface chemistry but may also promote a comprehensive understanding of the morphology‐function relationship on ZnO‐based electronics. [ABSTRACT FROM AUTHOR]

Slot‐die coating is a powerful method for upscaling the production of organic solar cells (OSCs) with low energy consumption print processes at ambient conditions. Herein, chlorobenzene (CB) and chloroform (CF) are compared as host solvents for printing films of the neat novel fused‐ring unit based wide‐bandgap donor polymer (PDTBT2T‐FTBDT), the small molecule nonfullerene acceptor based on a fused ring with a benzothiadiazole core (BTP‐4F) as well as the respective PDTBT2T‐FTBDT:BTP‐4F blend films at room temperature in air. Using CF printing of the PDTBT2T‐FTBDT:BTP‐4F active layer, OSCs with a high power conversion efficiency of up to 13.2% are reached in ambient conditions. In comparison to CB printed blend films, the active layer printed out of CF has a superior morphology, a smoother film surface and a more pronounced face‐on orientation of the crystallites, which altogether result in an enhanced exciton dissociation, a superior charge transport, and suppressed nonradiative charge carrier recombination. Based on in situ studies of the slot‐die coating process of PDTBT2T‐FTBDT, BTP‐4F, and PDTBT2T‐FTBDT:BTP‐4F films, the details of the film formation kinetics are clarified, which cause the superior behavior for CF compared to CB printing due to balancing the aggregation and crystallization of donor and acceptor. [ABSTRACT FROM AUTHOR]

Cooperative self‐assembly (co‐assembly) of diblock copolymers (DBCs) and inorganic precursors that takes inspiration from the rich phase separation behavior of DBCs can enable the realization of a broad spectrum of functional nanostructures with the desired sizes. In a DBC assisted sol–gel chemistry approach with polystyrene‐block‐poly(ethylene oxide) and ZnO, hybrid films are formed with slot‐die coating. Pure DBC films are printed as control. In situ grazing‐incidence small‐angle X‐ray scattering measurements are performed to investigate the self‐assembly and co‐assembly process during the film formation. Combining complementary ex situ characterizations, several distinct regimes are differentiated to describe the morphological transformations from the initially solvent‐dispersed to the ultimately solidified films. The comparison of the assembly pathway evidences that the key step in the establishment of the pure DBC film is the coalescence of spherical micelles toward cylindrical domains. Due to the presence of the phase‐selective precursor, the formation of cylindrical aggregates in the solution is crucial for the structural development of the hybrid film. The pre‐existing cylinders in the ink impede the domain growth of the hybrid film during the subsequent drying process. The precursor reduces the degree of order, prevents crystallization of the PEO block, and introduces additional length scales in the hybrid films. [ABSTRACT FROM AUTHOR]

Solvent additives enable the efficient modification of the morphology to improve the power conversion efficiency (PCE) of organic solar cells. However, the impact of solvent additive selectivity on the film morphology and formation kinetics is still unclarified. Herein, this work investigates two solvent additives, 1‐chloronaphthalene (1‐CN) and tetralin, characterized by their varying selectivity for the polymer donor (PBDB‐T‐2F) and the non‐fullerene small molecule acceptor (BTP‐C3‐4F). Specifically, 1‐CN exhibits superior solubility for BTP‐C3‐4F over PBDB‐T‐2F, whereas tetralin shows the opposite trend. The blend films with and without solvent additives are fabricated with the slot‐die coating at ambient conditions. Both solvent additives can promote larger phase separation and increase the size of crystals of the selectively dissolved component. In situ grazing‐incidence wide‐angle X‐ray scattering and UV–vis absorption spectra during printing unveil two distinct kinetic processes induced by 1‐CN and tetralin, leading to large‐sized crystals. 1‐CN can prolong the liquid‐solid phase separation to provide sufficient time for the BTP‐C3‐4F crystal growth but suppress the crystal growth of PBDB‐T‐2F. Tetralin can swell PBDB‐T‐2F and break down BTP‐C3‐4F crystals at the same time. Upon thermal annealing, the oversized crystals triggered by both solvent additives can be optimized to an appropriate size, resulting in an enhanced PCE. [ABSTRACT FROM AUTHOR]

The interface of organic solar cells plays a crucial role in device performance and stability. Several investigations demonstrated that the interface will affect the morphology and microstructure of the active layer, which is important for device performance. Here, several mercaptan derivatives are explored in green‐solvent based organic solar cells (PBDB‐TF‐T1: BTP‐4F‐12) as effective stabilization modifiers on ZnO. Operando grazing‐incidence wide/small‐angle X‐ray scattering (GIWAXS/GISAXS) provides a deep understanding of the degradation process during operation. The degradation process is driven by a compression of the molecule stacking as well as a decrease in the donor crystallinity, besides the known decomposition of the acceptor at the interface. Solar cell degradation comprises three stages, where an unexpected component from the acceptor appears in the second stage, simultaneously with a shapely shrinking micro‐structure. Furthermore, the interface modifier pentaerythritol tetrakis(3‐mercapto‐propionate) (PETMP) stabilizes the crystallinity of the donor as well as suppresses the decomposition of the acceptor, thus improving the device stability. The modification effect is caused by the interaction between Zn and S from the sulfhydryl groups of the mercaptan derivatives. Thus, studies of changes in the active layer morphology extend the knowledge from ex situ characterizations, broadening the understanding of the degradation mechanisms. [ABSTRACT FROM AUTHOR]

Organic conducting polymer poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) has garnered enormous attention in organic electronics due to its low-cost solution processability, highly tunable conductivity, superior mechanical flexibility, and good biocompatibility together with excellent atmospheric stability. Nevertheless, limited electrical properties and unfavorable water instability of pristine PEDOT:PSS film impede its further implementation in a broad spectrum of practical applications. In this work, the successful tailoring of the intrinsic electrostatic interaction within PEDOT:PSS and consequent optimized electrical properties are enabled by a simple yet effective ionic salt post-treatment strategy. The choice of zinc di[bis(trifluoromethylsulfonyl)imide] (Zn(TFSI) 2 ) not only endows the post-treated PEDOT:PSS film with high electrical properties but also other compelling characteristics, including superior water stability, excellent mechanical flexibility, and fast humidity responsiveness. Multidimensional characterizations are conducted to gain in-depth insights into the mechanisms underlying such improved performance, ranging from intermolecular interactions, polymer conformations, and doping levels to microstructural characteristics. Benefiting from these versatile properties, the as-prepared freestanding Zn(TFSI) 2 -post-treated PEDOT:PSS films can serve as promising candidates for high-performance polymeric materials integrated into multifunctional flexible electronics, including thermoelectric power generators, conductive hydrogels, and humidity-responsive actuators. This study demonstrates a facile methodology for the exploration of multifunctional conducting polymers, whose implications can extend across a wide range of next-generation wearable devices, bioelectronics, and soft robotics.