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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]

For realizing complicated shapes of the inner cavity of zinc alloy castings by pressure die casting, the problem of poor leachability has to be solved and the high-strength requirement of the water-soluble salt core should be met. High-melting potassium chloride salt and low-melting potassium nitrate salt were used as the core materials. High-strength binary composite water-soluble salt core (WSSC) was formed by the process of melting and gravity pouring. The performance characteristics of the potassium chloride core, potassium nitrate core, and binary composite WSSC (20% KCl-80% KNO3) were investigated. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) studies were performed to examine the micro-morphology and phase composition of WSSC. The results indicate the following:the binary composite WSSC has excellent comprehensive performance, its bending strength can exceed 21.2 MPa, the 24 h hydroscopicity rate is 0.568%, the water-soluble rate can exceed 208.63 kg·min-1·m-3 in water at 80℃ and its surface has no cracks and folds unlike the pure salt core. Crack growth in the binary composite salt core occurs by deflection, which is the main reason for the improvement in bending strength.

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]

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]