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The branched metal‐organic frameworks (MOFs) are the first superstructures of this kind, and the growth mechanism may explain crystal shapes of other materials. The mechanism of the formation of fascinating structures having a hedrite, sheaf or spherulite appearance are detailed. The branching can be controlled, resulting in crystals that either exhibit multiple generations of branching or a single generation. These structures might result from an increasing number of defects on fast‐grown rods. As the basal facets become less reactive, material is added to the prism facets, leading to secondary nucleation and triangular branches. These triangular structures are connected to the rod surface, growing longer than the central rod. Electron diffraction analyses show that the sheafs are polycrystalline structures with their fantails consisting of single‐crystalline nanorods deviating gradually from each other in their orientation. The crystallographic structure consists of channels with opposite handedness. The accessibility of the nanochannels and the porosity of the superstructures are demonstrated by chromophore diffusion into the channels. The confinement and alignment of the chromophores inside the channels resulted in polarized‐light dependent coloration of the crystals; the polycrystallinity generated areas having different optical properties. [ABSTRACT FROM AUTHOR]

Copyright of Implantologie is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

3D superstructures (3DSs) have attracted increasing interest because of the collective synergistic effects of individual building units, but their customization relies on tedious multistep strategy or high‐end nanofabrication technology. Herein, for the first time, a facile block copolymer micelle‐mediated anisotropic growth approach is reported to fabricate gold 3DSs consisting of tunable and intersecting lamellae with sawtooth‐like edges. The preparation of the 3DSs depends on the mediation of reduction kinetics of gold precursors and adsorption of block copolymer micelles on gold crystal surfaces using disulfiram as ligands. The thickness of lamellae in the 3DSs is controllable from ≈21 to 102 nm by adjusting the weight fraction of the micellar hydrophobicity blocks and the composed lamellar number is regulated from ≈3 to ≈30. Additional morphologies, such as a dendritic mesoporous structure and meatball‐like shapes, are obtained through controlling the extent of micelle swelling. Finite‐difference time‐domain simulations demonstrate that the unique 3DSs of gold lamellae with sawtooth‐like edges form abundant hotspots giving rise to surface‐enhanced Raman scattering (SERS). The 3DSs exhibit strong electromagnetic field enhancement and excellent performance as SERS substrates for detecting 4‐mercaptobenzoic acid. [ABSTRACT FROM AUTHOR]

The self‐assembly of inorganic nanocrystals offers an efficient way for the fabrication of functional materials. However, it is still challenging for the construction of multidimensional nanostructures with controllable shapes, compositions and functions. Here, a series of heterostructures in different dimensions by surface modification of polyoxometalate (POM) clusters is developed. Three kinds of POM clusters (phosphomolybdic acid (PMA), phosphotungstic acid (PTA) and silicotungstic acid (STA) and five kinds of metal oxides (TiO2, VOx, La2O3, In2O3 and Gd2O3) can be used as building blocks, and a class of 1D, 2D and 3D heterostructures can be achieved by the control of surface ligand coverage. Compared with individual building blocks and other cluster‐based superstructures, TiO2‐PMA superstructures exhibit enhanced catalytic activity toward thioether oxidations, which is attributed to the electron transfer between TiO2 and POM clusters. [ABSTRACT FROM AUTHOR]

The common neighbor analysis (CNA) for binary systems is a powerful method used to identify chemical ordering in intermetallics by unique indices. The capability of binary CNA, however, is largely restricted by the availability of indices for various ordered phases. In this study, CNA indices of 11 ordered phases derived from a face-centered cubic structure were introduced on a case-by-case basis. These phases, common in intermetallics containing platinum-group metals, include C11b, MoPt2, C6, B11, AgZr, A2B2[111], A2B2[113], Pt3Tc, A3B[011], A3B[111], and A3B[113]. The chemical order in static chemical perturbation, dynamic phase competition, and experimentally reconstructed nanophase alloys were identified using binary CNA. The results indicated that the proposed version of binary CNA exhibited significantly higher accuracy and robustness compared to the short-range order, polyhedral template matching, and the original binary CNA method. Benchmarked against available methods, the formation, decomposition, and competition of specifically ordered phases in bulks and nanoalloys were well reflected by present CNA, highlighting its potential as a robust and widely adopted tool for deciphering chemical ordering at the atomic level. [ABSTRACT FROM AUTHOR]

The coupling electrosynthesis involving CO2 upgrade conversion is of great significance for the sustainable development of the environment and energy but is challenging. Herein, we exquisitely constructed the self‐supported bimetallic array superstructures from the Cu(OH)2 array architecture precursor, which can enable high‐performance coupling electrosynthesis of formate and adipate at the anode and the cathode, respectively. Concretely, the faradaic efficiencies (FEs) of CO2‐to‐formate and cyclohexanone‐to‐adipate conversion simultaneously exceed 90% at both electrodes with excellent stabilities. Such high‐performance coupling electrosynthesis is highly correlated with the porous nanosheet array superstructure of CuBi alloy as the cathode and the nanosheet‐on‐nanowire array superstructure of CuNi hydroxide as the anode. Moreover, compared to the conventional electrolysis process, the cell voltage is substantially reduced while maintaining the electrocatalytic performance for coupling electrosynthesis in the two‐electrode electrolyzer with the maximal FEformate and FEadipate up to 94.2% and 93.1%, respectively. The experimental results further demonstrate that the bimetal composition modulates the local electronic structures, promoting the reactions toward the target products. Prospectively, our work proposes an instructive strategy for constructing adaptive self‐supported superstructures to achieve efficient coupling electrosynthesis. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Science & Engineering (1673-2812) is the property of Journal of Materials Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim of the study is to analyse the mechanical problems of implant restorations: the precise passive fit, the fracture resistance-aging, the micro fractures, the change in colour and the design of both infrastructure and superstructure. Material and methods We evaluate the same full arch restoration with the five most used material combinations and a mechanical failure test and numeric design simulations of forces at bone level. Results: Generally, two extensions failed faster than the single extension. Conclusions The patients’ expectations on the success of the implant and the predictability are high compared to their reluctance towards treatment costs and duration; it is particularly important to clarify this aspect from the beginning of the treatment.

Abstract The coupling electrosynthesis involving CO2 upgrade conversion is of great significance for the sustainable development of the environment and energy but is challenging. Herein, we exquisitely constructed the self‐supported bimetallic array superstructures from the Cu(OH)2 array architecture precursor, which can enable high‐performance coupling electrosynthesis of formate and adipate at the anode and the cathode, respectively. Concretely, the faradaic efficiencies (FEs) of CO2‐to‐formate and cyclohexanone‐to‐adipate conversion simultaneously exceed 90% at both electrodes with excellent stabilities. Such high‐performance coupling electrosynthesis is highly correlated with the porous nanosheet array superstructure of CuBi alloy as the cathode and the nanosheet‐on‐nanowire array superstructure of CuNi hydroxide as the anode. Moreover, compared to the conventional electrolysis process, the cell voltage is substantially reduced while maintaining the electrocatalytic performance for coupling electrosynthesis in the two‐electrode electrolyzer with the maximal FEformate and FEadipate up to 94.2% and 93.1%, respectively. The experimental results further demonstrate that the bimetal composition modulates the local electronic structures, promoting the reactions toward the target products. Prospectively, our work proposes an instructive strategy for constructing adaptive self‐supported superstructures to achieve efficient coupling electrosynthesis.

Controlling interactions among nanoparticles is paramount to achieving assemblies vital to technologies seeking to exploit their cutting-edge collective properties. Although various techniques have been advanced, robust ones are necessary for upscaling nanoparticle assembly and crystallization. Here, we show that by grafting gold nanoparticles (AuNPs) with charge-end-group-thiolated poly-(ethylene glycol), we control the charge of each AuNP. Such control facilitates the formation of various two-dimensional structures of oppositely charged binary constituents at vapor/liquid interfaces. Using surface-sensitive synchrotron X-ray diffraction techniques, we established the formation of distinct checkerboard square lattice structures at a range of pH values and molar ratios of the constituents. By regulating pH, the superlattices can transform from a square to a hexagonal lattice, or vice versa, and to a single-component superstructure at the interface. Our recipe for the control of charges and their consequent interactions among nanoparticles can be readily exploited in the assembly of photonics and plasmonics devices in two and three dimensions. [ABSTRACT FROM AUTHOR]

The helical twisting tendency of liquid crystals (LCs) is generally governed by the inherent configuration of the chiral emitter. Here, we introduce the multistage inversion of supramolecular chirality as well as circularly polarized luminescence (CPL) by manipulating the ratio of single enantiomeric emitters (R‐PCP) to LC monomers (5CB). Increasing the content of R‐PCP from 1 wt % to 3 wt % inverted the helix of LCs from left‐handed to right‐handed, accompanying a CPL sign changed from positive to negative. The biaxiality of chiral emitters, as well as the steric effect of chiral‐chiral and chiral‐achiral interaction, were identified as the reasons for helical sense inversion. Due to the strong helical twisting power, 4 wt % R‐PCP drove the photonic band gap (PBG) of chiral LCs to match up with their emission range, leading to an inversion of the CPL again with a high dissymmetry factor (≈1.2). Directly adjusting the PBG using chiral emitters is seldom achieved in cholesteric LCs. On this basis, an achiral sensitizer PtTPBP was assembled into the helical superstructure. The generation of triplet‐triplet annihilation‐induced upconverted CPL from R‐PCP and the downshifting CPL from PtTPBP with opposite rotation was achieved in a single chiral LC system by tuning the position of the PBG. [ABSTRACT FROM AUTHOR]

Defect and interface engineering, which can facilitate exceptional electrochemical stability and activity, are some of the most important strategies in devising electrode materials. However, the complex nanoscale chemistry and structure characteristics make the origin of electrochemical mechanism extremely difficult to understand. To eliminate this issue, the delicately designed 1D tungsten bronze superstructure anode, guided by defect and interface engineering, is successfully prepared for sodium storage to gain insight into the endogenous structure‐property relationships. It can realize the intensely enhanced Na+‐storage performance with a safe operating potential of ≈0.5 V, a high specific capacity of 228 mAh g−1 at 0.1 C and superior rate performance, which is attributed to the rapid electron and ion transfer process induced by abundant heterointerfaces. More importantly, it can convey an ultra‐stable long‐term cycling performance, with the capacity retention close to 90% after 4500 cycles at 5 C and 10000 cycles at 10 C, which can be explained by the inherently zero‐strain characteristic of a novel vacancy‐ordered superstructure in tungsten bronze Ba3.4Nb10O28.4 (BNO). This study reveals the structural origins of defect and interface engineering responsible for electrochemical mechanism, providing critical insight into the design of superior electrode materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Monolayer supertubes composed of carbon-armored platinum (Pt) nanocrystals were obtained by self-assembly. • The Pt utilization of the supertubes was 1.5 times higher than that of conventional Pt/C catalysts. • Such Pt supertubes exhibited remarkable electrocatalytic performances for ORR in acidic media. • Its superior catalytic durability was verified by using identical-location transmission electron microscopy. Self-assembled superstructures composed of nanocrystals (NCs) have shown immense potential for enhancing the performance in electrocatalytic applications. However, there has been limited research on the self-assembly of platinum (Pt) into low-dimensional superstructures as efficient electrocatalysts for oxygen reduction reaction (ORR). In this study, we designed a unique tubular superstructure composed of monolayer or sub-monolayer carbon-armored platinum nanocrystals (Pt NCs) using a template-assisted epitaxial assembly approach. The organic ligands on the surface of Pt NCs were in situ carbonized, resulting in few-layer graphitic carbon shells that encapsulate Pt NCs. Due to their monolayer assembly and tubular geometry, the Pt utilization of the supertubes was 1.5 times higher than that of conventional carbon-supported Pt NCs. As a result, such Pt supertubes exhibit remarkable electrocatalytic performance for the ORR in acidic media, with a high half-wave potential of 0.918 V and a high mass activity of 181 A g-1 Pt at 0.9 V, which are comparable to commercial carbon-supported Pt (Pt/C) catalysts. Furthermore, the Pt supertubes demonstrate robust catalytic stability, as confirmed by long-term accelerated durability tests and identical-location transmission electron microscopy. This study presents a new approach to designing Pt superstructures for highly efficient and stable electrocatalysis. [ABSTRACT FROM AUTHOR]

This article, published in the Romanian Journal of Oral Rehabilitation, provides a comprehensive analysis of mechanical problems associated with full arch implant superstructures in implantology. The study examines factors such as precise fit, fracture resistance, micro fractures, color changes, and design of infrastructure and superstructure. The results indicate that single extensions outperformed two extensions in terms of failure rates. The article emphasizes the importance of managing patient expectations and predicting implant success at the beginning of treatment. It also discusses the impact of occlusal forces, bruxism, and crown materials on implant prostheses. The text presents empirical data, statistical analysis, and regression models to explore the relationships between variables. It highlights the significance of material selection and patient-specific factors in dental restorations. The conclusions suggest the best-performing materials and call for further research and clinical follow-up. The text compiles various research studies and statistical data on dental implants and prosthetic materials, covering topics such as shock absorption capacity, occlusal concepts, bruxism, and monolithic zirconia crowns. The findings indicate that certain materials and occlusal concepts may impact the performance and longevity of dental implants. [Extracted from the article]

ObjectiveTo tackle the problem of the longitudinal strength of composite superstructures, the finite element analysis method is used to study their longitudinal bending characteristics and design requirements. MethodFirst, an analysis is made of the longitudinal strain distribution along the height direction of a simplified hull model with different lengths and the equivalent elastic moduli of superstructure materials, and the quadratic function is used to perform nonlinear fitting. Second, the design requirements of composite superstructures are proposed based on the fitting results and explained in terms of both structural size and material properties. Finally, based on the concept of bending moment effectiveness and national military standards, a superstructure method with different elastic moduli and lengths is proposed that fully participates in longitudinal bending determination. ResultsThe results show that glass fiber and carbon fiber reinforced plastic reach the longitudinal strength requirements of superstructures, and composite superstructures longer than 0.3 times the length of the hull should be included in section stiffness checks. ConclusionThe results of this study can provide references for the future design of naval ships with composite materials.

Self‐assembled chiral superstructures represent an emerging class of chiral materials that can possess unique and collective chiroptical properties superior to their building blocks. However, facile construction of such chiral assemblies, especially those with circularly polarized light emission (CPLE), is still challenging. Here, a simple solution‐based self‐assembly of colloidal chiral superstructures from copper‐penicillamine nanosheets is reported. These chiral copper superstructures feature flower‐like morphology, and exhibit CPLE that is significantly stronger than their unassembled counterparts. In addition, the handedness and the morphology complexity of the superstructures can be independently manipulated by the chirality of penicillamine enantiomers and self‐assembly process, respectively. Besides the structural manipulation, CPLE property can be tuned by doping with other metal ions such as silver. The unique chiroptical and colloidal properties of the chiral copper superstructures as well as the simplicity of the self‐assembly enable rational design of CPLE materials with hierarchical chirality and may advance the applications in chiral sensing, asymmetric catalysis, and novel optoelectronics. [ABSTRACT FROM AUTHOR]

In turbulent boundary layers, streamwise elongated regions of high- and low-momentum in the log-law layer that can extent up to several boundary layer thicknesses are often referred to as turbulent superstructures. These structures contain a relatively large portion of the layer's turbulent kinetic energy and have been shown to interact with the near-wall flow structures. In the last few decades extensive research on zero-pressure gradient (ZPG) turbulent boundary layers has been done, however by comparison, the structural characteristics for adverse pressure gradient turbulent (APG) boundary layer flows are much less studied despite their strong significance aero-hydrodynamic vehicle design. Therefore, the three-dimensional dynamics of turbulent superstructures in a turbulent boundary layer flow are investigated in the Atmospheric Wind Tunnel Munich (AWM) using a multi-camera 3D time-resolved Lagrangian particle tracking approach. In this study, Lagrangian and Eulerian statistics will be used to characterize the dynamics and interaction of turbulent superstructures within a zero pressure gradient (ZPG) turbulent boundary layer at Re τ = 5000 or Re θ = 14 000 that then flows over a curved plate subjected to a favorable (FPG) and strong adverse (APG) pressure gradient, which eventually separates. An Eulerian analysis, using multi-point correlations of 3D velocity fields, found that the average superstructure topology is modulated by decelerating flow in the APG region when compared to the ZPG region, however the basic shape and spanwise pattern is preserved. Looking into the behavior of individual trajectories, it was found that the dispersion of single particles along trajectories in the log-law layer are capable of moving more than the average Eulerian superstructure spacing in the spanwise direction. Furthermore, the mean square of the single particle dispersion indicates that the maximum dispersion in the spanwise direction comes from particles released at the wall-normal location corresponding to the so-called "second-peak/plateau" region in the streamwise normal Reynolds stress. [ABSTRACT FROM AUTHOR]

A variable temperature single crystal X‐ray diffraction study of the ternary compound, Cu4TiTe4 is reported between 200–400 K. The temperature dependent study indicates the compound undergoes an order‐disorder phase transition at ∼320 K. Below the transition temperature, the phase that crystallizes in the primitive cubic space group P4‾ ${\bar{4}}$ 3 m with lattice parameter of a≈5.9 Å, transforms into the two‐fold superstructure. It is modeled as a fourfold twinned rhombohedral structure. The transition is reversible. To relate the phases, a group‐subgroup symmetry relations are established. Upon decreasing temperature, the atomic ordering is noticed in the occupationally disordered Cu‐sites of Cu4TiTe4. This characteristic structural rearrangement may have a significant impact on the electronic structure of Cu4TiTe4. Hence, the detailed structural characterization is supposed to be useful for further understanding of thermoelectric transport properties in the Cu4TiTe4. [ABSTRACT FROM AUTHOR]

A variable temperature single crystal X‐ray diffraction study of the ternary compound, Cu4TiTe4 is reported between 200–400 K. The temperature dependent study indicates the compound undergoes an order‐disorder phase transition at ∼320 K. Below the transition temperature, the phase that crystallizes in the primitive cubic space group P4‾ ${\bar{4}}$ 3 m with lattice parameter of a≈5.9 Å, transforms into the two‐fold superstructure. It is modeled as a fourfold twinned rhombohedral structure. The transition is reversible. To relate the phases, a group‐subgroup symmetry relations are established. Upon decreasing temperature, the atomic ordering is noticed in the occupationally disordered Cu‐sites of Cu4TiTe4. This characteristic structural rearrangement may have a significant impact on the electronic structure of Cu4TiTe4. Hence, the detailed structural characterization is supposed to be useful for further understanding of thermoelectric transport properties in the Cu4TiTe4. [ABSTRACT FROM AUTHOR]

Polychalcogenides REX2‐δ (X=S, Se, Te; 0≤δ≤0.2) of trivalent rare earth metals RE have been investigated in recent years to shed light on the structural diversity as a function of compositional, metric, thermodynamic, and electronic situation. Whereas the former aspects have comparable influence on the structures of all polychalcogenides REX2‐δ, the bonding situation was assumed different for tellurides due to tellurium's higher tendency to delocalize electrons. The crystal structures generally contain puckered [REX] double slabs and planar [X] layers, the latter hosting different distortions from a square‐like arrangement. The distortion patterns of sulfides and selenides can be understood by a Zintl‐type approach; they are dominated by localization of valence electrons in mono‐ (X2−) or dinuclear (X22−) anions only. This review discusses crystal structures of some rare‐earth metal polytellurides RETe2‐δ (0≤δ≤0.2) and bonding features in the chalcogenide layers and relates them to their sulfide and selenide counterparts. [ABSTRACT FROM AUTHOR]

The structural chemistry of Laves phases, especially with respect to their superstructures induced by coloring and distortions is discussed. Starting from the three classical Laves phases MgCu2, MgZn2 and MgNi2, the more complex Komura phases are derived. Different possibilities of their description are summarized. In the second part, the superstructures are discussed based on their respective prototypes. The crystal chemical relationships are illustrated based on group‐subgroup descriptions using the Bärnighausen formalism. [ABSTRACT FROM AUTHOR]

The common neighbor analysis (CNA) for binary systems is a powerful method used to identify chemical ordering in intermetallics by unique indices. The capability of binary CNA, however, is largely restricted by the availability of indices for various ordered phases. In this study, CNA indices of 11 ordered phases derived from a face-centered cubic structure were introduced on a case-by-case basis. These phases, common in intermetallics containing platinum-group metals, include C11b, MoPt2, C6, B11, AgZr, A2B2[111], A2B2[113], Pt3Tc, A3B[011], A3B[111], and A3B[113]. The chemical order in static chemical perturbation, dynamic phase competition, and experimentally reconstructed nanophase alloys were identified using binary CNA. The results indicated that the proposed version of binary CNA exhibited significantly higher accuracy and robustness compared to the short-range order, polyhedral template matching, and the original binary CNA method. Benchmarked against available methods, the formation, decomposition, and competition of specifically ordered phases in bulks and nanoalloys were well reflected by present CNA, highlighting its potential as a robust and widely adopted tool for deciphering chemical ordering at the atomic level.

Improving the intrinsic catalytic activity of electrocatalysts is considered to be the "gold standard" to inhibit the shuttle effect in Li–S batteries. The question of how to expose active sites for anchoring and catalytic conversion of the polysulfides represents the direction of this research. The assembly of 0D nanoparticles or 2D nanosheets into 3D spherical superstructure is one of the problems of materials synthesis. Here, a spherical superstructure hafnium diboride derived from metal‐organic framework (MOF) nanoparticles is synthesized by one‐step borification. Benefiting from its unique superstructure, the obtained HfB2 exhibits excellent catalytic activity for the conversion of polysulfide. Theoretical calculations indicate that the strong spin–orbital coupling property of electron configuration of 5d Hf induces p orbitals of nonmetallic atoms closer to the Fermi level, thus endowing the anions with redox activity and unconventional superconductivity. These merits enable the HfB2‐based sulfur cathode to deliver a high initial discharge capacity of 1433 mAh g−1 at 0.2 C and 580 mAh g−1 at 5 C. With sulfur loading of 12.8 mg cm−2 and electrolyte dosage of 4 µL mg−1, the areal capacity can reach 15.5 mAh cm−2. This work provides a new understanding for designing superstructure borides involving 5d metals in Li–S batteries. [ABSTRACT FROM AUTHOR]

Almost 25% of the environmental pollution, measured by the indicator of global greenhouse emissions, is emitted by transport. Changes in the mobility behavior of the population will be essential if the 17 UN Sustainable Development Goals (SDGs) and the goals of the EU Commission's Green Deal are to be attained. Accordingly, the existing infrastructure has to transform into a sustainable transport infrastructure through further optimizations in the future. Therefore, continuous optimizations and improvements of designs, materials, and processes are crucial to achieving long-term sustainability. This study investigates different superstructures with the method of life cycle assessment using the example of the emerging high-performance infrastructure at the Brenner Base Tunnel (BBT). The study analyzes all relevant life cycle stages (A1–C4) and validates different effects of service lifetimes of superstructure elements on the open track and in the tunnel. The results, which are presented in the form of GWP, AP, and NRCED, show that there is environmental reduction potential, especially in the stage of use. As more frequent modernization cycles and the associated remanufacturing of superstructure elements account for a significant proportion of the total environmental impact, lifetime extending optimization of products yields improvements in the ecological footprint. [ABSTRACT FROM AUTHOR]

The fabrication of hybrid assemblies into highly ordered functional materials remains a major challenge. Here, two carbazole derivatives equipped with an alkyl thiol and Br-substituted (CZBr) or unsubstituted (CZH) were designed. These molecules were hybridized with an SnS2 nanosheet, and an organic-induced multistep self-assembly approach was successfully applied in the CZBr and SnS2 systems. First, the CZBr was anchored on SnS2 nanosheets via the alkyl thiols' chemical bonding. Then, the strong π–π interaction of CZBr drove the hybrid nanosheets to stack as superstructures. The nanoflower morphology of SnS2 could thus be converted to a nanotube of the SnS2-CZBr hybrid material. Due to this unique structure, the as-prepared organic–inorganic hybrid materials exhibit excellent efficiency for the photocatalytic degradation of methyl orange (MO). The best degradation effect of SnS2-CZBr after 1 h of illumination was 93.48%; the value was 53.78% for SnS2. The photocatalysts described here are a class of organic-driven hierarchical self-assembly organic–inorganic hybrid semiconductor materials. [ABSTRACT FROM AUTHOR]

All inorganic CsPbBr3 superstructures (SSs) have attracted much research interest due to their unique photophysical properties, such as their large emission red-shifts and super-radiant burst emissions. These properties are of particular interest in displays, lasers and photodetectors. Currently, the best-performing perovskite optoelectronic devices incorporate organic cations (methylammonium (MA), formamidinium (FA)), however, hybrid organic–inorganic perovskite SSs have not yet been investigated. This work is the first to report on the synthesis and photophysical characterization of APbBr3 (A = MA, FA, Cs) perovskite SSs using a facile ligand-assisted reprecipitation method. At higher concentrations, the hybrid organic–inorganic MA/FAPbBr3 nanocrystals self-assemble into SSs and produce red-shifted ultrapure green emissions, meeting the requirement of Rec. 2020 displays. We hope that this work will be seminal in advancing the exploration of perovskite SSs using mixed cation groups to further improve their optoelectronic applications. [ABSTRACT FROM AUTHOR]

Intricate superstructures possess unusual structural features and promising applications. The preparation of superstructures with single‐crystalline nature are conducive to understanding the structure–property relationship, however, remains an intriguing challenge. Herein we put forward a new hierarchical assembly strategy towards rational and precise construction of intricate single‐crystal superstructures. Firstly, two unprecedented superclusters in Rubik's cube's form with a size of ≈2×2×2 nm3 are constructed by aggregation of eight {Pr4Sb12} oxohalide clusters as secondary building units (SBUs). Then, the Rubik's cubes further act as isolable tertiary building units (TBUs) to assemble diversified single‐crystal superstructures. Importantly, intermediate assembly states are captured, which helps illustrate the evolution of TBU‐based superstructures and thus provides a profound understanding of the assembly process of superstructures at the atomic level. [ABSTRACT FROM AUTHOR]

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The superstructure composed of various functional building units is promising nanostructure for lithium‐ion batteries (LIBs) anodes with extreme volume change and structure instability, such as silicon‐based materials. Here, a top‐down route to fabricate Si/SiO2@graphene superstructure is demonstrated through reducing silicalite‐1 with magnesium reduction and depositing carbon layers. The successful formation of superstructure lies on the strong 3D network formed by the bridged‐SiO2 matrix coated around silicon nanoparticles. Furthermore, the mesoporous Si/SiO2 with amorphous bridged SiO2 facilitates the deposition of graphene layers, resulting in excellent structural stability and high ion/electron transport rate. The optimized Si/SiO2@graphene superstructure anode delivers an outstanding cycling life for ≈1180 mAh g−1 at 2 A g−1 over 500 cycles, excellent rate capability for ≈908 mAh g−1 at 12 A g−1, great areal capacity for ≈7 mAh cm−2 at 0.5 mA cm−2, and extraordinary mechanical stability. A full cell test using LiFePO4 as the cathode manifests a high capacity of 134 mAh g−1 after 290 loops. More notably, a series of technologies disclose that the Si/SiO2@graphene superstructure electrode can effectively maintain the film between electrode and electrolyte in LIBs. This design of Si/SiO2@graphene superstructure elucidates a promising potential for commercial application in high‐performance LIBs. [ABSTRACT FROM AUTHOR]

The emergence of lamellar nanofluidic membranes offers feasible routes for developing highly efficient, mechanically robust, and large‐scale devices for osmotic energy harvesting. However, inferior ion permeability associated with their relatively long channels limits ionic flux and restricts their output performance. Herein, a superstructured graphene oxide membrane is developed to allow programmable topological variation in local geometry and contain laminar spaces inside. Such deliberate design offers excess specific area as well as nanofluidic channels to modulate transmembrane ionic transportation while concomitantly retaining similar nanoconfined environment in contrast to planar ones, leading to considerable enhancement of ionic permeability without compromising selectivity. This can be highly favorable in terms of osmotic energy harvesting, where the superstructured membranes offer a power output much higher than those of conventional planar ones. Besides, the superstructure design also endows the resulting membranes with benign biofouling resistance, which can be crucial to their long‐term usage in converting osmotic energy. This study highlights the importance of membrane topographies and presents a general design concept that could be extended to other nanoporous membranes to develop high‐performance nanofluidic devices. [ABSTRACT FROM AUTHOR]

Peptides show tremendous promise in synthesizing metal–peptide superstructures with tailored shapes and functions. However, bottom‐up control of the polymorphs of these superstructures using a single short peptide without molecular modification has not been mechanistically clarified. Therefore, an approach to constructing gold–peptide superstructures with unprecedented structural diversity using a tyrosine‐rich short peptide is developed, based on the assembling and mineralizing attributes of tyrosine. One‐step UV irradiation of peptide/gold‐salt systems enables on‐site mineralization of gold ions, permitting controlled solvent‐dependent fabrication of various superstructures. 0D colloids, 2D sheets, 3D superspheres, and 3D hollow capsules are produced via one‐pot reactions in a pH‐10 buffer, at the interface of a toluene–water biphasic system, in water, and in toluene‐in‐water emulsions, respectively, whereas 1D rod/fibril structures are produced using rapidly assembling peptides (A, F, I, L, N, V, Y, and D as X in YY‐X‐YY) in a two‐step process. Several peptide derivatives, which also exhibit assembling and biomineralizing abilities and form various superstructures, validate the functionality of the tyrosine‐rich peptide. This study sheds light on the design and development of diverse gold‐peptide superstructures for applications including catalysis, sensing, imaging, and photothermal therapy. [ABSTRACT FROM AUTHOR]

The self-assembly pattern of functionalized chitosan (CS), in various solvent mixtures, was discussed here. The previously synthesized amphiphilic thiobarbiturate-derived chitosan (CS-TBA) molecule (where the chitosan backbone was relatively more hydrophobic and the thiobarbiturate moiety was relatively more hydrophilic) was subjected to different solvent mixtures for this purpose. Then the morphological changes of the aggregates were studied and analyzed from the perspective of size and shape through various conventional techniques. One of the components of the solvent mixture was water, whereas another component was a different polar protic solvent i.e.; methanol and polar aprotic solvents such as tetrahydrofuran, acetonitrile and dioxane. The superstructures were characterized using field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), cryo transmission electron microscope (cryo-TEM) and differential light scattering (DLS) methodologies. Finally, the usability of the solvent-dependent morphologies was deliberated in this article. Through the detailed spectroscopic analysis, we observed various unique and magnificent morphologies in terms of size and shapes in different solvent mixtures (protic as well as aprotic and different in terms of polarity index). The astonishing superstructures also have fascinating dye encapsulation abilities (above 80% encapsulation for hydrophobic as well as a hydrophilic dye in case of methanol/water solvent mixture) in different solvent mixtures which could be applied in the field of self-assembly and dye removal industries. [ABSTRACT FROM AUTHOR]

This study employs aberration-corrected transmission electron microscopy to provide definitive evidence of cation ordering within the superstructure of LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523), a prominent Ni-rich ternary cathode material, characterized by wave vector q = 1/3(2 a * - b *). We show that this ordering can be enhanced through controlled heating. Comparative analysis of LiNi x Co y Mn z O 2 samples with different compositions revealed that Mn ions are crucial for superstructure formation. The battery performance test shows that the superstructure has no obvious effect on the voltage platform during the charge-discharge cycle, but has a negative effect on the cycle performance and structural stability. This study elucidates the origin and detrimental effects of superstructures, advancing the understanding of their impact on battery performance, which is vital for the future development of ternary cathode materials.

To endow non-antibacterial molecules with highly efficient bactericide activity is an important but challenging issue. Herein, a kind of cell-penetrating peptide octa-arginine (R8) is found to be effective in activating antibacterial ability when assembling with anionic surfactant sodium dodecyl sulfate (SDS), while individual R8 or SDS shows poor or no antibacterial ability. By combined electrostatic, hydrogen bond, and hydrophobic interactions, R8 and SDS associate into wormlike micelle and lamellar structure by forming supramolecular self-assembling units, depending on their charge ratio (CR). The lamellar aggregates show particularly high antibacterial activities against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). Interestingly, E. coli and S. aureus are killed by membrane-disrupting and membrane-penetrating mechanisms, respectively. Furthermore, in vivo experiments evidence that the R8/SDS lamellar aggregates accelerate the recovery of bacteria-infected wounds, wherein the reduced inflammation and promoted angiogenesis are clearly presented. This study proves that highly efficient bactericidal activity is triggered by the synergistic action of penetrating peptide and anionic amphiphiles, thus providing a new strategy to realize highly efficient and targetable antibacterial application., (© 2024 Wiley‐VCH GmbH.)

Layered manganese oxides adopting pre‐accommodated cations have drawn tremendous interest for the application as cathodes in aqueous zinc‐ion batteries (AZIBs) owing to their open 2D channels for fast ion‐diffusion and mild phase transition upon topochemical (de)intercalation processes. However, it is inevitable to see these "pillar" cations leaching from the hosts owing to the loose interaction with negatively charged Helmholtz planes within the hosts and shearing/bulking effects in 2D structures upon guest species (de)intercalation, which implies a limited modulation to prevent them from rapid performance decay. Herein, a new class of layered manganese oxides, Mg0.9Mn3O7·2.7H2O, is proposed for the first time, aims to achieve a robust cathode for high‐performance AZIBs. The cathode can deliver a high capacity of 312 mAh g−1 at 0.2 A g−1 and exceptional cycling stability with 92% capacity retention after 5 000 cycles at 5 A g−1. The comprehensive characterizations elucidate its peculiar motif of pined Mg‐□Mn‐Mg dumbbell configuration along with interstratified hydrogen bond responsible for less Mn migration/dissolution and quasi‐zero‐strain characters. The revealed new structure‐function insights can open up an avenue toward the rational design of superstructural cathodes for reversible AZIBs. [ABSTRACT FROM AUTHOR]

Anionic redox provides an effective way to overcome the capacity bottleneck of sodium‐ion batteries. A dominant role is played by the arrangement of alkali A and transition metal M in the NaxAyM1‐yO2 superstructure. Here, in situ X‐ray diffraction and ex situ 7Li nuclear magnetic resonance of P2 type Na0.6Li0.2Mn0.8O2 with ribbon‐ordered superstructure illustrate structural changes and explain the evolution of the electrochemical behavior of electrodes comprising this active mass, during cycling. Upon substitution of a small amount of manganese by iron, Na0.67Li0.2Mn0.73Fe0.07O2 is formed with a honeycomb‐ordered superstructure. Experimental characterizations and theoretical calculations elucidate the effect of iron on oxygen redox activity. The iron‐doped material considerably outperforms the undoped Na0.6Li0.2Mn0.8O2 as a cathode material for rechargeable Na‐ion batteries. This research reveals the effect of superstructure transformation on the electrochemical properties and offers a new perspective on element substitution in anionic redox active cathode materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • HMCSs can be used as nano-reactors to control the growth of nickel silicate nanoflakes. • The core-shell superstructures significantly enhance the structural stability and conductivity of the Ni 3 Si 2 O 5 (OH) 4 /C materials. • The S1 electrode shows a superior SAC of 28.7 mg g−1 with an initial NaCl concentration of 584 mg L−1 at 1.2 V. In this work, we propose a novel strategy to fabricate nickel silicate nanoflakes inside hollow mesoporous carbon spheres (Ni 3 Si 2 O 5 (OH) 4 /C). Hollow mesoporous carbon spheres (HMCSs) can well regulate and limit the growth of Ni 3 Si 2 O 5 (OH) 4 nanosheets, which obviously enhance the structural stability and conductivity of the composites. The core-shell Ni 3 Si 2 O 5 (OH) 4 /C superstructure has been proven to possess an extremely excellent electrosorption capacity of 28.7 mg g−1 at 1.2 V under a NaCl concentration of 584 mg L−1 for capacitive deionization (CDI). This outstanding property can be attributed to the core-shell superstructure with ultrathin Ni 3 Si 2 O 5 (OH) 4 nanosheets as the stable core and mesoporous carbon as the conductive shell. This work will provide a direction for the application of core-shell superstructure carbon-based nanomaterials as high-performance electrode materials for CDI. [ABSTRACT FROM AUTHOR]

Background: There is currently a lack of guidelines for clinicians regarding titanium hypersensitivity in implant dentistry. Diagnostic tests such as the epicutaneous test or the lymphocyte transformation test showed inconsistent results regarding reliability and validity and thus, evidence-based consensus recommendations regarding diagnostic and therapeutic options may be helpful in clinical decision-making. Therefore, the German S3 guideline on titanium hypersensitivity in implant dentistry was developed. Findings: In the objectives, procedure, voting method and venue were defined and the consensus participants were invited. A systematic literature research was performed, and the overall quality of the evidence was rated according to the GRADE working group. Eight recommendations were formulated within the framework of a structured consensus conference under independent moderation and could be voted on with strong consensus (> 95% agreement). The formulated statements and recommendations were developed in small groups according to the guidelines of the Association of the Scientific Medical Societies in Germany (AWMF) and were discussed and agreed upon in the plenum. Conclusions: For reasonable decision-making, a patient's clinical symptoms should be regarded as leading parameters, which are usually expressed by a local inflammatory reaction with subsequent disturbed osseous integration. Allergy tests, such as the epicutaneous test or the lymphocyte transformation test are not helpful in titanium intolerance assessments, since these tests indicate T cell-mediated allergies, which are not observed in titanium intolerance reactions. Other metals and impurities that might be present in superstructures or alloys also need to be considered as the cause of an intolerance reaction and a trigger for contact sensitization. In the case of a suspected titanium particle-related, local immunologically induced inflammatory reaction with subsequent impaired osseous integration, dental ceramic implants can be considered as a therapeutic option. [ABSTRACT FROM AUTHOR]

Modulating intermolecular charge‐transfer (ICT) interactions between specific donor and acceptor species in host–guest systems is a big challenge and full of research value in supramolecular chemistry and materials science. In this work, a strategy to modulate the supramolecular ICT interactions in the solid state is developed by compressing the binding cavity of a macrocyclic host named perethylated leaning pillar[6]arene (p‐EtLP6). The solid‐state ICT affinities of p‐EtLP6 toward multi‐types of electron‐deficient planar guests could be significantly enhanced by transforming the macrocyclic backbone from the original para‐bridged mode into a hybrid para‐ and meta‐bridged isomeric form (m‐EtLP6). X‐ray single‐crystal structural analyses incorporating theoretical calculation demonstrate that the improved ICT affinities are mainly attributed to the superior host–guest size fit arising from the compressed binding cavity in m‐EtLP6 as compared with p‐EtLP6. [ABSTRACT FROM AUTHOR]

[Display omitted] • Layer-by-layer stacked vertical CS mode BW-TENG was fabricated. • Multi-layered superstructures of TiO 2 /PVA were used as tribonegative layer. • The output power density of 5.66 W·m−2 was observed with a loading of 10 MΩ. • Humidity sensing characteristics due to layered MXene stacked structure. • BW-TENG showed biomechanical energy harvesting and self-powered sensing. Selecting distinct materials to design a tribopositive and tribonegative electrode pair for a triboelectric nanogenerator (TENG) device is a challenging task, as the interfacial electric field causes surface charges to diffuse into the air or within the material itself, leads to charge deterioration. To address these challenges, there is a strong demand for engineered materials and electrode designs that enable effective charge accumulation and trapping to regulate their performance optimally. Herein, we introduce a unique electrode design for a contact-separation (CS) mode triboelectric nanogenerator TENG featuring multilayered Ti 3 C 2 T x MXene/Kapton as tribonegative electrodes. For the tribopositive electrode, we developed an innovative synthesis strategy to create MXene-seeded layered TiO 2 superstructures/PVA-based tribopositive electrodes. After optimization of both triboelectric layers, the optimized TENG showed an open-circuit voltage (V oc) ∼ 120 V, short-circuit current (I sc) ∼ 25 μA, and power density of 5.66 W·m−2. The surface terminations groups in highly conductive black MXene nanosheets and the oxygen vacancies in TiO 2 -layered superstructures provide abundant charge accumulation and trapping sites due to organized multilayered structures at both ends. Moreover, the induced polarization in the tribopositive layer due to the hybrid film could further hinder the free electrons' drift to the bottom electrode, preventing charge recombination. The optimized TENG was tested as a pressure sensor to monitor different sensitive physiological movements of the human body. Further application of the designed TENG has been revealed by humidity sensing characteristics, powering LEDs, stopwatches, pedometers, and swiftly charging micro-capacitors by utilizing direct output power. By employing a controlled synthesis strategy, our approach leverages the unique properties of MXenes to function as both tribo-positive and tribonegative electrodes within the same device. This dual-function capability simplifies material selection and enhances overall device performance, presenting a transformative solution for next-generation TENG applications. [ABSTRACT FROM AUTHOR]

While it is known that the double-layer Bi 2 Sr 2 CaCu 2 O 8 + y (BSCCO) cuprate superconductor exhibits a one-dimensional (1D) incommensurate superlattice (IS), the effect of IS on the electronic structure remains elusive. Following the recent shift of interest from an underdoped phase to optimum and overdoped phases in BSCCO by increasing the hole doping x, controlled by the oxygen interstitials concentration y, here we focus on the multiple splitting of the density of states (DOS) peaks and emergence of higher order van Hove singularities (VHS) due to the 1D incommensurate superlattice. It is known that the 1D incommensurate wave vector q = ϵ b (where b is the reciprocal lattice vector of the orthorhombic lattice) is controlled by the misfit strain between different atomic layers in the range 0.209 – 0.215 in BSCCO and in the range 0.209 – 0.25 in Bi 2 Sr 2 Ca 1 − x Y x Cu 2 O 8 + y (BSCYCO). This work reports the theoretical calculation of a complex pattern of VHS due to the 1D incommensurate superlattice with large 1D quasi-commensurate supercells with the wave vector ϵ = 9 / η in the range 36 > η > 43 . The similarity of the complex VHS splitting and appearing of higher order VHS in a mismatched CuO 2 bilayer with VHS due to the moiré lattice in strained twisted bilayer graphene is discussed. This makes a mismatched CuO 2 bilayer quite promising for constructing quantum devices with tuned physical characteristics. [ABSTRACT FROM AUTHOR]

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Abstract Fullerene assembling with specific donor molecules would yield multifunctional metamaterials via the collective behavior, wherein linear acenes are widely used as donor molecules to construct the charge‐transfer heterojunction structure with fullerene. However, they are generally prepared by vacuum deposition due to the insoluble property of high‐performance linear acenes molecules in common solvents, which makes the construction of fullerene with insoluble donor molecules still be a big challenge in the solution‐processed method. To this end, chemical modification provides an effective solution‐processed strategy to construct donor and acceptor systems. Here, the C60‐pentacene is assembled into controllable flower‐like superstructures by the surface grafting method. It is found that the nanofeatures of the microflowers could be regulated by temperature, resulting in dense‐flakes morphology at room temperature and loose flakes at high temperatures. Furthermore, the dense‐flakes microflowers structures with less mass but better crystalline structure exhibit better optoelectronic properties. Our results reveal an effective control on the nanofeatures of the self‐assembled fullerenes complex superstructures and their role for the optoelectronic performance, which may promote the exploring of fullerene superstructures as photodetectors.