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Randomly organizing hyperuniform fluid induced by reciprocal activation is a non-equilibrium fluid with vanishing density fluctuations at large length scales such as crystals. Here, we extend this new state of matter to a closed manifold, namely a spherical surface. We find that the random organization on a spherical surface behaves similar to that in two dimensional Euclidean space, and the absorbing transition on a sphere also belongs to the conserved directed percolation universality class. Moreover, the reciprocal activation can also induce a non-equilibrium hyperuniform fluid on a sphere. The spherical structure factor at the absorbing transition and the non-equilibrium hyperuniform fluid phases are scaled as S(l → 0) ∼ (l/R)0.45 and S(l → 0) ∼ l(l + 1)/R2, respectively, which are both hyperuniform according to the definition of hyperuniformity on a sphere with l, the wave number, and R, the radius of the spherical surface. We also consider the impact of inertia in realistic hyperuniform fluids, and it is found only by adding an extra length-scale, above which hyperuniform scaling appears. Our finding suggests a new method for creating non-equilibrium hyperuniform fluids on closed manifolds to avoid boundary effects. [ABSTRACT FROM AUTHOR]

Understanding molecular design rules for stretchable polymer semiconductors is important for enabling next generation stretchable electronic circuits. To simultaneously improve both electrical properties and mechanical stretchability, a design strategy is reported in introducing conjugated rigid fused‐rings with bulky side groups in semiconducting polymers. In this work, the understanding of this design concept is improved by systematically investigating the effect of different types of bulky side groups asymmetrically substituted on conjugated polymer semiconductor backbones. Specifically, four types of side groups are investigated, including naphthalene (NaPh), biphenyl (PhPh), thienylphenyl (ThPh), and alkylphenyl (C4Ph), asymmetrically substituted on benzodithiophene units, namely asy‐BDT. With the four types of side groups installed on BDT‐containing conjugated polymers in an asymmetrical fashion, it is observed that they reduced the polymer chain aggregation and film crystallinity, hence improving the film stretchability. Furthermore, the fully conjugated polymer backbone allows maintenance of good charge carrier mobilities. Specifically, polymer PDPP‐C4Ph (with C4Ph side groups) shows the highest mobility in the fully stretchable transistor and maintained its mobility even after being subjected to hundreds of stretching‐releasing cycles at 25% strain. Overall, the results provide anunderstanding of the use of asymmetrically substituted fused‐ring conjugated polymer structures to tune mechanical and charge transport properties. [ABSTRACT FROM AUTHOR]

• A novel CA@DF separator has been developed by coating CA and PVDF on commercial DF. • CA@DF separator can inhibit the growth of dendrites. • CA@DF separator demonstrate improved tensile strength and zinc ion migration number. • CA@DF separator has extremely low cost with only 1/221 cost of GF separator. • The batteries equipped with the CA@DF separator displays an ultralong lifespan. At present, the commonly used glass fiber (GF) separators in AZIBs possess many defects, such as lack zinophilic active sites, low ionic conductivity, poor mechanical strength, and high cost, which leading to the growth of dendrites and cause short circuits, thus resulting in deteriorated cyclic life. Herein, a novel CA@DF separator has been developed by coating molten blend of cellulose acetate (CA) and polyvinylidene fluoride (PVDF) on commercial dust-free fabric (DF) substrate and subsequent phase inversion. Due to the large number of active sites provided by the zinophilic –OH groups derived from CA, more the nucleation sites of Zn2+ are offered by the as-obtained CA@DF separator, which leads to an uniform deposition of Zn2+ of preferred (0 0 2) crystallographic orientation. Furthermore, as-obtained CA@DF separator demonstrate not only high tensile strength of 23.08 MPa, which is 51 times of the GF separator but also improved Zn2+ migration number (τ) (0.58 for CA@DF vs. 0.31 for GF). Moreover, the CA@DF separator has cost with only 1/221 cost of GF separator. Impressively, the symmetric cell equipped with the CA@DF separator displays an ultralong lifespan of over 2000 h at 0.5 mA cm−2 and 1000 h at 3 mA cm−2. Specifically, the CA@DF separator also improves the cycling stability of the Zn//V 2 O 5 cell with a reversible capacity of 78 mAh g−1 at 1A g−1 after 1000 cycles. This simple, reliable, and low-cost separator provides new insights into the design and industrial production of electrochemical energy storage device separators. [ABSTRACT FROM AUTHOR]

The side-wall pressure distribution in static silos is an important and open problem related to storage safety of granular materials. Referring to Lvin's theory [Powder Technology 4, 280 (1971)] and Rodolfo's 2D numerical result [Phys. Rev. E 97.1(2018)], a new theoretical model of side-wall pressure is established by assuming the friction coefficient as well as the ratio of horizontal to vertical stress changing with depth position in granular columns. Furthermore, the transition of stress state between hydrostatic-like and Janssen-like in a cylindrical granular container with flat bottom is systematically investigated by our model and experiment, and finally an empirical expression describing this transition is proposed. Unlabelled Image • A theoretical model of side-wall pressure distribution for silos is established. • The mechanism of peak pressure value is found to be the transition of stress state. • An empirical expression describing the transition of stress state is proposed. • The experimental result is in good agreement with the theoretical calculation. [ABSTRACT FROM AUTHOR]

Metal‐halide perovskite semiconductors have garnered great attention in optoelectronic devices due to their remarkable properties and processing capabilities. Among them, tin (Sn2+) perovskites stand out as promising candidates for use as channel layers in high‐performance p‐channel thin‐film transistors (TFTs) owing to their excellent hole transport property. In this study, a multi A‐cation approach is applied to pure Sn2+ perovskite, incorporating a small amount (7 mol%) of bulky PEA+ cation. This addition greatly improved the crystallinity and orientation of 3D FA0.9Cs0.1SnI3 perovskite, leading to optimized p‐channel Sn2+‐perovskite TFT with a hole mobility of ≈18 cm2 V−1 s−1, a high on/off current ratio of 108, and a small subthreshold swing of 0.5 V dec−1. These TFTs also exhibit a low contact resistance of 87 Ω·cm, attributed to the improved electrode/perovskite channel interface. Furthermore, the TFTs are utilized as an electrical characterization platform to study the charge transport properties and interfacial defects using the low‐frequency noise method, providing insights into the interface properties of perovskite electronic devices. [ABSTRACT FROM AUTHOR]

Developing artificial protective layers is an effective strategy to address the issue of dendrites for aqueous Zn‐metal batteries (ZMBS). However, drawbacks such as rough microscopic morphology, excessive thickness, and single functionality remain, limiting the attainment of a stable zinc anode. Herein, a novel multifunctional organic–inorganic hybrid artificial protective layer is produced by splicing inorganic fragments onto organic materials in situ using a chemical sewing. The protective layer is well‐compatible and also retains the function of organic and inorganic materials, which not only inhibits dendrite production but also alleviates Zn corrosion. The Si─OH bond of the zincophilic group enables planar Zn deposition while forming hydrogen bonds with water, suppressing water activity near the anode and reducing the hydrogen evolution reaction. As expected, the Zn||Zn symmetric cell with a protective layer provides high cycling stability of more than 1960 h at 1 mA cm−2, which is about 28 times higher than that of the symmetric cell assembled without the protective layer. More importantly, a Zn||V2O5 full cell with an ultra‐long lifetime has been achieved with an artificial protective layer. This work provides a potential viable path to achieve long‐lived ZMBS. [ABSTRACT FROM AUTHOR]

Molecular aggregation and crystallization during film coating play a crucial role in the realization of high‐performing organic photovoltaics. Strong intermolecular interactions and high solid‐state crystallinity are beneficial for charge transport. However, fast crystallization during thin‐film drying often limits the formation of the finely phase‐separated morphology required for efficient charge generation. Herein, the authors show that twisted acceptor‐donor‐acceptor (A‐D‐A) type compounds, containing an indacenodithiophene (IDT) electron‐rich core and two naphthalenediimide (NDI) electron‐poor units, leads to formation of mostly amorphous phases in the as‐cast film, which can be readily converted into more crystalline domains by means of thermal annealing. This design strategy solves the aforementioned conundrum, leading to an optimal morphology in terms of reduced donor/acceptor domain‐separation sizes (ca. 13 nm) and increased packing order. Solar cells based on these acceptors with a PBDB‐T polymer donor show a power conversion efficiency over 10% and stable morphology, which results from the combined properties of desirable excited‐state dynamics, high charge mobility, and optimal aggregation/crystallization characteristics. These results demonstrate that the twisted A‐D‐A motif featuring thermally‐induced crystallization behavior is indeed a promising alternative design approach toward more morphologically robust materials for efficient organic photovoltaics. [ABSTRACT FROM AUTHOR]