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The trigonal planar unit possesses significant hyperpolarizability and polarizability anisotropy, which makes it useful for optimizing nonlinear optical (NLO) materials, however, chalcogenide with this unit has seldom been reported. In this work, a novel approach is introduced by integrating the unprecedented trigonal planar MS₃ (M = Cd/In, Hg/In) motifs into the nearly optically isotropic tetrahedral units, resulting in two novel chalcogenides CsM₂In₂S₆ (M = Cd/In, 1; Hg/In, 2). Notably, structures 1 and 2 feature nearly planar triangular units at the center, encircled by three trimers, further interconnecting each other to create 3D frameworks. Importantly, phases 1 and 2 display phase-matching (PM) capabilities, primarily attributed to incorporating trigonal planar MS₃ units that additionally enhance polarizability anisotropy. Furthermore, compounds 1 and 2 demonstrate moderate second-harmonic generation (SHG) signals (0.70 and 0.84 × AgGaS2@1.7 µm). This study pioneers an efficient strategy for the design of infrared NLO crystals with PM capabilities.

Zinc-ion capacitors (ZICs) have attracted great attention due to a series of advantages. However, the cathode materials are still the bottleneck for high-performance ZICs to be achieved. Therefore, ZIF-8-derived porous carbons are one of the most promising candidates but ZIF-8 nanoparticles with different sizes exhibited various electrochemical performances in ZICs. Herein, a series of monodispersed ZIF-8 nanoparticles are first prepared by a temperature-controlled process to fabricate the corresponding ZIF-8-based porous carbon nanoparticles with pre-designed sizes. The as-prepared materials have been tested as cathode materials in ZICs. Thus, their size effect allowed us to disclose its correlation with other factors such as ion transport/storage and capacitance. The results reveal that the optimal-sized porous carbon particles can effectively shorten the ion transport distance and accelerate the ion diffusion rate, resulting in lower electrical resistance, larger ion diffusion coefficients, and faster electron transport. The presented findings can facilitate the design of new advanced cathode materials paving the way for the development of high-performance cathode materials for ZICs in the future.

As active materials for large-radius Na⁺ storage, metal sulfide (MS) anodes still face several challenges, including poor intrinsic electric conductivity, severe volume change along with the shuttle and dissolution effects of discharge-produced polysulfides. In this work, the mixed nickel-manganese sulfides (NiMnS) in the morphology of uniform 2D ultrathin nanosheets are derived from layered metal-organic frameworks (MOFs), where the NiS-MnS heterojunction are accommodated in carbon matrix with S dopant (NiMnS/SC). Through experiments and density functional theory (DFT) simulations, it is revealed that the carbon matrix with S dopant has multifunctional effects on active NiMnS during the charge/discharge process, including conductive intermediary, electrochemical active site, physical barrier, and chemical adsorption. This work may promote the design of MS-based electrodes in SIBs and extend the application of carbon material with S dopant in Na-S batteries.

The presence of dense collagen fibers is a typical characteristic of triple-negative breast cancer (TNBC). Although these fibers hinder drug penetration and reduce treatment efficacy, the depletion of the collagen matrix is associated with tumor metastasis. To address this issue, epigallocatechin-3-gallate (EGCG) is first exploited for disrupting the dense collagenous stroma and alleviate fibrosis by specifically blocking the TGF-β/Smad pathway in fibroblasts and tumor cells when intraperitoneally administrated in TNBC tumor-bearing mice. A methotrexate (MTX)-loaded dual phosphate- and pH-responsive nanodrug (pHA@MOF-Au/MTX) is next engineered by integrating Fe-based metal-organic frameworks and gold nanoparticles for improved chemo/chemodynamic therapy of TNBC. Surface modification with pH (low)-insertion peptide substantially enhanced the binding of the nanodrug to 4T1 cells owing to tumor stroma remodeling by EGCG. High-concentration EGCG inhibited glutathione peroxidase by regulating mitochondrial glutamine metabolism, thus facilitating tumor cell ferroptosis. Furthermore, sequential EGCG and pHA@MOF-Au/MTX treatment showed remarkable anti-tumor effects in a mouse model of TNBC, with a tumor growth inhibition rate of 79.9%, and a pulmonary metastasis rate of 96.8%. Altogether, the combination strategy developed in this study can improve the efficacy of chemo/chemodynamic therapy in TNBC and represents an innovative application of EGCG.

The preparation of ethylene (C₂H₄) by electrochemical CO₂ reduction (ECO₂R) has dramatically progressed in recent years. However, the slow kinetics of carbon-carbon (C-C) coupling remains a significant challenge. A generalized facet reconstruction strategy is reported to prepare a 3-phase mixed pre-catalyst (Cu₃N-300) of Cu₃N, Cu₂O, and CuO by controlling the calcination temperature and to obtain the derived Cu catalyst (A-Cu₃N-300-0.5) enriched with Cu(111)/Cu(200) grain boundaries (GBs) by subsequent constant potential reduction. Its Faraday efficiency (FE) toward C₂H₄ at a low reaction potential of -1.07 V (vs reversible hydrogen electrode (RHE)) is 46.03%, which is much higher than the other 3 derived Cu catalysts containing single Cu(111) facets (24.89% and 24.52%) and Cu(111)/Cu(111) GBs (28.66%). Combining in situ experimental and theoretical computational studies, abundant Cu(111)/Cu(200) GBs is found to enhance CO₂ activation and significantly promote the formation and adsorption of *CO intermediates, thereby lowering the activation energy barrier of C-C coupling and increasing the FE of C₂H₄.

The unique properties of confined water molecules within polymer networks have garnered extensive research interest in energy storage, catalysis, and sensing. Confined water molecules exhibit higher thermodynamic stability compared to free water, which reduces decomposition and evaporation of water in hydrogel electrolyte system. Herein, a facile strategy is developed to limit active water molecules in a hydrogel network via hydrogen bonding within a topological network. The design of this gel enhances hydrogen bonding between the gel network and water molecules, thereby improving stability by constructing interpenetrating networks. Using this design, the topological network gel is selected as the electrolyte for batteries, demonstrating an extended electrochemical window from 2.37 V with polyvinyl alcohol gel to 2.96 V, indicating superior confinement of water molecules by hydrogen bonds in the topological network. Additionally, batteries and capacitors assembled with the topological gel exhibit high-capacity retention rates of 94.25% after 20 000 cycles at a current density of 1.0 A g^-1 and 87.63% after 10 000 cycles at a current density of 0.5 A g^-1, respectively. This study demonstrates the feasibility of using a topological gel design to enhance gel electrolyte stability, offering a promising avenue for future research in regulating topological networks within gels for various applications.

The development of novel nano-single-atom-site catalysts with optimized electron configurations and active water adsorption (^*H₂O) to release hydrogen protons (^*H) is paramount for photocatalytic hydrogen evolution (PHE), a multi-step reaction process involving two electrons. In this study, an atom-confinement and thermal reduction strategy is introduced to achieve synergistic Ag single-atoms (Ag₁) and nanoparticles (Ag_NPs) confined within carbon nitride nanotubes (Ag_1+NPs-CN) for enhanced photocatalytic hydrogen evolution. Mechanistic investigations reveal that H₂O adsorption/dissociation predominantly occurs at Ag₁ sites, while Ag_NPs sites notably facilitate H₂ release, indicating the synergistic effect between Ag₁ and Ag_NPs in the H₂ evolution reaction. Furthermore, the effective confining of Ag species is beneficial for trapping electrons in highly active reaction regions, while the "electronic metal-support interactions" (EMSIs) of Ag_NPs and Ag₁-C₂N sites regulate the d-band centers and effectively optimize the adsorption/desorption of intermediates in photocatalytic hydrogen evolution, leading to enhanced H₂ production performance. This work demonstrates the potential of the construction of synergistic photocatalysts for efficient energy conversion and storage; Hydrogen production; Nanoparticles; Photocatalysis; Single atom; and Synergistic effect.

The rise in global temperatures and environmental contamination resulting from traditional fossil fuel usage has prompted a search for alternative energy sources. Utilizing solar energy to drive the direct splitting of water for hydrogen production has emerged as a promising solution to these challenges. Covalent organic frameworks (COFs) are ordered, crystalline materials made up of organic molecules linked by covalent bonds, featuring permanent porosity and a wide range of structural topologies. COFs serve as suitable platforms for solar-driven water splitting to produce hydrogen, as their building blocks can be tailored to possess adjustable band gaps, charge separation capabilities, porosity, wettability, and chemical stability. Here, the impact of the interface in the context of the photocatalytic reaction is focused and propose strategies to enhance the hydrogen production performance of COFs photocatalysis. In particular, how hybrid photocatalytic interfaces affect photocatalytic performance is focused.

Silicon (Si) is a promising anode material for next-generation lithium-ion batteries (LIBs) due to its high specific capacity and abundance. However, challenges such as significant volume expansion during cycling and poor electrical conductivity hinder its large-scale application. In this study, the multifunction of sodium polyacrylate (PAAS) utilized to develop a hierarchical porous silicon-carbon anode (Si/SiO_x@C) through a simple and efficient method. The hierarchical porous structure successively consists of nano-silicon cores, SiO_x encapsulating layers, surrounding space, and phenolic resin-derived carbon shells with carbon chains connecting the SiO_x layers and carbon shells in the space. The SiO_x nanolayers promote Li⁺ transport, while excess PAAS, removed by washing, generates space for volume expansion, improving cycling performance. Residual carbon chains of PAAS and carbon shells form a conducting carbon network, enhancing electron transport and rate performance. As an anode for LIBs, the composite delivers a high reversible capacity of 685.3 mAh g⁻¹ after 1000 cycles at 1 C with a capacity retention rate of 54.7%. Full cells with the Si/SiO_x@C anode and LiNi_0.8Co_0.1Mn_0.1O₂ cathode exhibit an excellent capacity retention rate of 96.8% after 200 cycles at 1 C. This work provides a novel approach for the rational design and engineering of advanced LIBs.

The escalating demand for high-power and compact-size advanced electronic devices and power systems necessitates polymers to exhibit superior electrical properties even under harsh environments. However, reconciling the seemingly contradictory attributes of excellent electrical properties and thermal stability poses a formidable challenge for current epoxy polymer (EP) materials and their applications. To meet the need, here two classes of bi-aryl diamine curing agents are described that enable polymers to exhibit well-balanced thermal and dielectric properties with functional bridging groups. A weak conjugation system in highly thermally stable polymers with an aromatic backbone is constructed, using electron-modulating bridging groups to immobilize intramolecular free carriers by tailoring trap sites, and bulky bridging groups to prevent molecular stacking to inhibit intermolecular charge transport. The resultant polymer exhibits a volume resistance of 7.45 × 10¹² Ω m and a direct current breakdown strength of 368.74 kV mm^-1 at 120 °C, which are 2.2 and 2.4 times higher than that of commercial anhydride-cured EP, respectively. It is demonstrated to be due to the inhibition of charge injection and transport. The proposed aromatic amine multimolecule approach, combined with diverse functional bridging groups, is a promising direction for exploring next-generation EP insulation materials suitable for extreme conditions.