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The multiphoton excitation pathways of plasmonic nanorod assemblies are described. By using dolmen structures formed from the directed assembly of three gold nanorods, plasmon-mediated three-photon excitation is resolved. These high-order multiphoton excitation channels were accessed by resonantly exciting a hybrid mode of the dolmen structure that was resonant with the 800-nm carrier wavelength of an ultrafast laser system. Rotation of the exciting field polarization to a non-resonant configuration did not generate third-order responses. Hence, the multiphoton excitation and resultant non-equilibrium electron distributions were generated by structure- and mode-selective excitation. Correlation between high-order and resonant plasmon excitation was achieved through sub-cycle time-resolved interferometric detection of incoherent nonlinear emission signals. The results illustrate the advantages of nonlinear optical interferometry and Fourier analysis for distinguishing plasmon-mediated processes from those that do not require plasmon excitation. [ABSTRACT FROM AUTHOR]

We have used surface plasmon resonant metal gratings to induce and probe the dielectric response (i.e., electro-optic modulation) of ionic liquids (ILs) at electrode interfaces. Here, the cross-plane electric field at the electrode surface modulates the refractive index of the IL due to the Pockels effect. This is observed as a shift in the resonant angle of the grating (i.e., Δϕ), which can be related to the change in the local index of refraction of the electrolyte (i.e., Δnlocal). The reflection modulation of the IL is compared against a polar (D2O) and a non-polar solvent (benzene) to confirm the electro-optic origin of resonance shift. The electrostatic accumulation of ions from the IL induces local index changes to the gratings over the extent of electrical double layer (EDL) thickness. Finite difference time domain simulations are used to relate the observed shifts in the plasmon resonance and change in reflection to the change in the local index of refraction of the electrolyte and the thickness of the EDL. Simultaneously using the wavelength and intensity shift of the resonance enables us to determine both the effective thickness and Δn of the double layer. We believe that this technique can be used more broadly, allowing the dynamics associated with the potential-induced ordering and rearrangement of ionic species in electrode–solution interfaces. [ABSTRACT FROM AUTHOR]

Exploring the plasmon energy dissipation mechanism of bimetallic nanostructures after photoexcitation is of great significance for controlling energy transfer in plasmonic applications. The absorption, scattering, and extinction spectra of Ag@Cu, Ag@Pt, and Ag@Co core–shell nanostructures are calculated by finite element method, and the energy dissipation process is visualized by using particle trajectory and the absorbed power density distribution. The absorption/scattering ratio of the core–shell nanostructures, the shell absorptivity, the time-domain electric field as well as the extra-core electron arrangements of Ag, Cu, Pt, and Co atoms are analyzed for figuring out the energy dissipation mechanism. The results show that when a non-plasmonic metal is coated on the surface of a plasmonic metal, the plasmon energy dissipates preferentially in the shell, and the degree of dissipation depends on the imaginary part of the dielectric constant of the shell and the core. A larger dielectric constant of the shell can cause more energy to be transferred from the plasmonic metal to the shell region. This study provides the fundamental physical framework and design principles for plasmonic nanostructures. [ABSTRACT FROM AUTHOR]

Timely and effective interventions after tracheal mucosal injury are lack in clinical practices, which elevate the risks of airway infection, tracheal cartilage deterioration, and even asphyxiated death. Herein, we proposed a biomaterial-based strategy for the repair of injured tracheal mucosal based on a copper hydrogen phosphate nanosheets (CuHP NSs) functionalized commercial hydrogel (polyethylene glycol disuccinimidyl succinate-human serum albumin, PH). Such CuHP/PH hydrogel achieved favorable injectability, stable gelation, and excellent adhesiveness within the tracheal lumen. Moreover, CuHP NSs within the CuHP/PH hydrogel effectively stimulate the proliferation and migration of endothelial/epithelial cells, enhancing angiogenesis and demonstrating excellent tissue regenerative potential. Additionally, it exhibited significant inhibitory effects on both bacteria and bacterial biofilms. More importantly, when injected injured site of tracheal mucosa under fiberoptic bronchoscopy guidance, our results demonstrated CuHP/PH hydrogel adhered tightly to the tracheal mucosa. The therapeutic effects of the CuHP/PH hydrogel were further confirmed, which significantly improved survival rates, vascular and mucosal regeneration, reduced occurrences of intraluminal infections, tracheal stenosis, and cartilage damage complications. This research presents an initial proposition outlining a strategy employing biomaterials to mitigate tracheal mucosal injury, offering novel perspectives on the treatment of mucosal injuries and other tracheal diseases.

Bacterial nanocellulose (BNC) is a durable, flexible, and dynamic biomaterial capable of serving a wide variety of fields, sectors, and applications within biotechnology, healthcare, electronics, agriculture, fashion, and others. BNC is produced spontaneously in carbohydrate-rich bacterial culture media, forming a cellulosic pellicle via a nanonetwork of fibrils extruded from certain genera. Herein, we demonstrate engineering BNC-based scaffolds with tunable physical and mechanical properties through postprocessing. Human skeletal muscle myoblasts (HSMMs) were cultured on these scaffolds, and in vitro electrical stimulation was applied to promote cellular function for tissue engineering applications. We compared physiologic maturation markers of human skeletal muscle myoblast development using a 2.5-dimensional culture paradigm in fabricated BNC scaffolds, compared to two-dimensional (2D) controls. We demonstrate that the culture of human skeletal muscle myoblasts on BNC scaffolds developed under electrical stimulation produced highly aligned, physiologic morphology of human skeletal muscle myofibers compared to unstimulated BNC and standard 2D culture. Furthermore, we compared an array of metrics to assess the BNC scaffold in a rigorous head-to-head study with commercially available, clinically approved matrices, Kerecis Omega3 Wound Matrix (Marigen) and Phoenix as well as a gelatin methacryloyl (GelMA) hydrogel. The BNC scaffold outcompeted industry standard matrices as well as a 20% GelMA hydrogel in durability and sustained the support of human skeletal muscle myoblasts in vitro. This work offers a robust demonstration of BNC scaffold cytocompatibility with human skeletal muscle cells and sets the basis for future work in healthcare, bioengineering, and medical implant technological development.

Recent discoveries in biology have highlighted the importance of protein and RNA-based condensates as an alternative to classical membrane-bound organelles. Here, we demonstrate the design of pure RNA condensates from nanostructured, star-shaped RNA motifs. We generate condensates using two different RNA nanostar architectures: multi-stranded nanostars whose binding interactions are programmed via linear overhangs, and single-stranded nanostars whose interactions are programmed via kissing loops. Through systematic sequence design, we demonstrate that both architectures can produce orthogonal (distinct and immiscible) condensates, which can be individually tracked via fluorogenic aptamers. We also show that aptamers make it possible to recruit peptides and proteins to the condensates with high specificity. Successful co-transcriptional formation of condensates from single-stranded nanostars suggests that they may be genetically encoded and produced in living cells. We provide a library of orthogonal RNA condensates that can be modularly customized and offer a route toward creating systems of functional artificial organelles for the task of compartmentalizing molecules and biochemical reactions.

Diabetic foot ulcers (DFU) are chronic, refractory wounds caused by diabetic neuropathy, vascular disease, and bacterial infection, and have become one of the most serious and persistent complications of diabetes mellitus because of their high incidence and difficulty in healing. Its malignancy results from a complex microenvironment that includes a series of unfriendly physiological states secondary to hyperglycemia, such as recurrent infections, excessive oxidative stress, persistent inflammation, and ischemia and hypoxia. However, current common clinical treatments, such as antibiotic therapy, insulin therapy, surgical debridement, and conventional wound dressings all have drawbacks, and suboptimal outcomes exacerbate the financial and physical burdens of diabetic patients. Therefore, development of new, effective and affordable treatments for DFU represents a top priority to improve the quality of life of diabetic patients. In recent years, nanozymes-based diabetic wound therapy systems have been attracting extensive interest by integrating the unique advantages of nanomaterials and natural enzymes. Compared with natural enzymes, nanozymes possess more stable catalytic activity, lower production cost and greater maneuverability. Remarkably, many nanozymes possess multienzyme activities that can cascade multiple enzyme-catalyzed reactions simultaneously throughout the recovery process of DFU. Additionally, their favorable photothermal-acoustic properties can be exploited for further enhancement of the therapeutic effects. In this review we first describe the characteristic pathological microenvironment of DFU, then discuss the therapeutic mechanisms and applications of nanozymes in DFU healing, and finally, highlight the challenges and perspectives of nanozyme development for DFU treatment.

Dental implant therapy, established as standard-of-care nearly three decades ago with the advent of microrough titanium surfaces, revolutionized clinical outcomes through enhanced osseointegration. However, despite this pivotal advancement, challenges persist, including prolonged healing times, restricted clinical indications, plateauing success rates, and a notable incidence of peri-implantitis. This review explores the biological merits and constraints of microrough surfaces and evaluates the current landscape of nanofeatured dental implant surfaces, aiming to illuminate strategies for addressing existing impediments in implant therapy. Currently available nanofeatured dental implants incorporated nano-structures onto their predecessor microrough surfaces. While nanofeature integration into microrough surfaces demonstrates potential for enhancing early-stage osseointegration, it falls short of surpassing its predecessors in terms of osseointegration capacity. This discrepancy may be attributed, in part, to the inherent dichotomy kinetics of osteoblasts, wherein increased surface roughness by nanofeatures enhances osteoblast differentiation but concomitantly impedes cell attachment and proliferation. We also showcase a controllable, hybrid micro-nano titanium model surface and contrast it with commercially-available nanofeatured surfaces. Unlike the commercial nanofeatured surfaces, the controllable micro-nano hybrid surface exhibits superior potential for enhancing both cell differentiation and proliferation. Hence, present nanofeatured dental implants represent an evolutionary step from conventional microrough implants, yet they presently lack transformative capacity to surmount existing limitations. Further research and development endeavors are imperative to devise optimized surfaces rooted in fundamental science, thereby propelling technological progress in the field.

Tobacco mild green mosaic virus (TMGMV)-like nanocarriers were designed for gene delivery to plant cells. High aspect ratio TMGMVs were coated with a polycationic biopolymer, poly(allylamine) hydrochloride (PAH), to generate highly charged nanomaterials (TMGMV-PAH; 56.20 ± 4.7 mV) that efficiently load (1:6 TMGMV:DNA mass ratio) and deliver single-stranded and plasmid DNA to plant cells. The TMGMV-PAH were taken up through energy-independent mechanisms in Arabidopsis protoplasts. TMGMV-PAH delivered a plasmid DNA encoding a green fluorescent protein (GFP) to the protoplast nucleus (70% viability), as evidenced by GFP expression using confocal microscopy and Western blot analysis. TMGMV-PAH were inactivated (iTMGMV-PAH) using UV cross-linking to prevent systemic infection in intact plants. Inactivated iTMGMV-PAH-mediated pDNA delivery and gene expression of GFP in vivo was determined using confocal microscopy and RT-qPCR. Virus-like nanocarrier-mediated gene delivery can act as a facile and biocompatible tool for advancing genetic engineering in plants.

The effects of isothermal annealing on the self-assembled nanostructures of spinel manganese oxide ZnMnGaO4 were investigated using transmission electron microscopy and x-ray diffraction. The checkerboard nanostructures and zigzag nanostructures (named "Sierra" nanostructures) coexisted owing to the chemical phase separation of Mn3+ and Ga3+ ions by isothermal annealing at 575 °C. It was observed that the checkerboard nanostructures were dominant in short-time annealing and that the volume fraction of the Sierra nanostructures became more prominent as the annealing period increase. The interdiffusion of Mn3+ and Ga3+ is indicated to play an important role in gaining the total energy of the system by the reduction in the local strain caused by the formation of nanostructures. These results provide further insights into the fabrication of distinct types of nanostructures in complex transition-metal compounds. [ABSTRACT FROM AUTHOR]

The effects of isothermal annealing on the self-assembled nanostructures of spinel manganese oxide ZnMnGaO4 were investigated using transmission electron microscopy and x-ray diffraction. The checkerboard nanostructures and zigzag nanostructures (named "Sierra" nanostructures) coexisted owing to the chemical phase separation of Mn3+ and Ga3+ ions by isothermal annealing at 575 °C. It was observed that the checkerboard nanostructures were dominant in short-time annealing and that the volume fraction of the Sierra nanostructures became more prominent as the annealing period increase. The interdiffusion of Mn3+ and Ga3+ is indicated to play an important role in gaining the total energy of the system by the reduction in the local strain caused by the formation of nanostructures. These results provide further insights into the fabrication of distinct types of nanostructures in complex transition-metal compounds. [ABSTRACT FROM AUTHOR]

Circular dichroism (CD) spectra for pseudo-two-dimensional chiral nanomaterials were systematically investigated and analyzed in relation to the rotational symmetry of the nanomaterials. Theoretically, an ideal two-dimensional chiral matter is CD inactive for light incident normal to the plane if it possesses threefold or higher rotational symmetry. If the matter has two- or onefold rotational symmetry, it should exhibit CD activity, and the CD signal measured from the back side of the matter is expected to be inverted from that measured from the front side. For pseudo-two-dimensional chiral gold nanostructures fabricated on glass substrates using electron beam lithography, matter with fourfold rotational symmetry is found to be CD active, even when special care is taken to ensure that the optical environments for the front and back sides of the sample are equivalent. In this case, the CD signal measured from the back side is found to be almost exactly the same as that measured from the front side. It is revealed that the observed chiro-optical behavior arises from three-dimensional chiral characteristics due to differences in the surface shape between the front and back sides of the structures. For matter that is two- or onefold rotationally symmetric, the CD signal measured from the back side is not coincident with that from the front side. For certain wavelength regions, the CD signals measured from the front side and back side are observed to be similar, while at other wavelengths, the inverted component of the CD signals is found to dominate. The observed CD spectral behavior for reciprocal optical measurement configurations is considered to be determined by a balance between the in-plane isotropic and anisotropic components of the chiral permittivity. [ABSTRACT FROM AUTHOR]

Many experimental and computational efforts have sought to understand DNA origami folding, but the time and length scales of this process pose significant challenges. Here, we present a mesoscopic model that uses a switchable force field to capture the behavior of single- and double-stranded DNA motifs and transitions between them, allowing us to simulate the folding of DNA origami up to several kilobases in size. Brownian dynamics simulations of small structures reveal a hierarchical folding process involving zipping into a partially folded precursor followed by crystallization into the final structure. We elucidate the effects of various design choices on folding order and kinetics. Larger structures are found to exhibit heterogeneous staple incorporation kinetics and frequent trapping in metastable states, as opposed to more accessible structures which exhibit first-order kinetics and virtually defect-free folding. This model opens an avenue to better understand and design DNA nanostructures for improved yield and folding performance.

A wooden house frame consists of many different lumber pieces, but because of the regularity of these building blocks, the structure can be designed using straightforward geometrical principles. The design of multicomponent protein assemblies, in comparison, has been much more complex, largely owing to the irregular shapes of protein structures1. Here we describe extendable linear, curved and angled protein building blocks, as well as inter-block interactions, that conform to specified geometric standards; assemblies designed using these blocks inherit their extendability and regular interaction surfaces, enabling them to be expanded or contracted by varying the number of modules, and reinforced with secondary struts. Using X-ray crystallography and electron microscopy, we validate nanomaterial designs ranging from simple polygonal and circular oligomers that can be concentrically nested, up to large polyhedral nanocages and unbounded straight 'train track' assemblies with reconfigurable sizes and geometries that can be readily blueprinted. Because of the complexity of protein structures and sequence-structure relationships, it has not previously been possible to build up large protein assemblies by deliberate placement of protein backbones onto a blank three-dimensional canvas; the simplicity and geometric regularity of our design platform now enables construction of protein nanomaterials according to 'back of an envelope' architectural blueprints.

The design of protein-protein interfaces using physics-based design methods such as Rosetta requires substantial computational resources and manual refinement by expert structural biologists. Deep learning methods promise to simplify protein-protein interface design and enable its application to a wide variety of problems by researchers from various scientific disciplines. Here, we test the ability of a deep learning method for protein sequence design, ProteinMPNN, to design two-component tetrahedral protein nanomaterials and benchmark its performance against Rosetta. ProteinMPNN had a similar success rate to Rosetta, yielding 13 new experimentally confirmed assemblies, but required orders of magnitude less computation and no manual refinement. The interfaces designed by ProteinMPNN were substantially more polar than those designed by Rosetta, which facilitated in vitro assembly of the designed nanomaterials from independently purified components. Crystal structures of several of the assemblies confirmed the accuracy of the design method at high resolution. Our results showcase the potential of deep learning-based methods to unlock the widespread application of designed protein-protein interfaces and self-assembling protein nanomaterials in biotechnology.

The semiconducting behavior of two-dimensional (2D) metal nanostructures has recently attracted much interest for their possible applications in optoelectronics and others. In particular, tuning the bandgap of such nanostructures can open up a new avenue for fabricating functional nano-devices. In the present article, we report the synthesis of 2D metallic Zn nanosheets at room temperature using a ball mill, which is capable of producing large-scale materials in a single run. Initially, nanoplates were formed for ball milling the octahedral-shaped Zn nanoparticles for the time of milling of 6 h. Subsequent ball milling for another 6 h leads these nanoplates to nearly uniform nanosheets. The thickness of these 2D nanostructures was found to decrease with an increase in the time of milling. Visible photoluminescence (PL) emissions centered at ∼3, ∼2.9, and ∼2.75 eV were observed from all the Zn particles showing semiconductor behavior. The origin of such semiconductor behavior was explained based on the radiative transition of electrons from the sp band to the upper states of the 3d band. This argument was confirmed through the studies of photoelectron spectroscopy and the first principle calculations employing density functional theory (DFT). Furthermore, excitation-dependent PL studies indicated that the bandgap of the 2D Zn nanostructures decreased with the increase in the ball milling time. Therefore, a redshift in the bandgap was observed with the increase in the ball milling time. Such changes in the bandgap with the thickness of 2D Zn nanostructures were also verified from the studies of DFT. Thus, the present study demonstrated that the bandgap of 2D metallic Zn nanostructures could be effectively tuned by reducing the thickness. [ABSTRACT FROM AUTHOR]

The present investigation involves the in situ growth of Ag nanostructures (NSs) onto a rough Cu surface, accomplished through a cost-effective and straightforward fabrication process. The inherent characteristics of the Cu surface contribute to a certain degree of a surface-enhanced Raman spectroscopy (SERS) signal. Upon integration with Ag NSs, the Cu surface serves as an exceptionally sensitive and consistently uniform substrate for surface-enhanced Raman spectroscopy. Notably, a singular substrate accommodates the simultaneous detection of four distinct probe molecules. Subsequent SERS analyses of Ag NSs on Cu were executed under varying laser power conditions. Intriguingly, despite the escalation in laser power, no substantial shifts were discerned in the peak positions corresponding to the probe molecules. Consequently, it can be inferred that, for investigations where peak position shifts hold significance, the utilization of a thermally conductive material in fabricating SERS-active substrates could confer notable advantages. [ABSTRACT FROM AUTHOR]

From the perspective of a bond-order-length-strength correlation, we put forward an analytical solution to describe the size, shape, and wall thickness dependency of melting temperature, entropy, and enthalpy for metallic nanostructures. Theoretical reproduction of measurements clarified that (i) when the crystal size reduces, the atomic coordination number lowers, the atomic cohesive energy decreases, and the surface-to-volume ratio increases; (ii) at the same equivalent radius, with the decrease in the number of sides for polyhedral nanoparticles and polygonal nanowires or nanotubes, the melting temperature, entropy, and enthalpy depress; and (iii) the melting temperature, entropy, and enthalpy of nanotubes are always lower than those of nanowires with the same cross-sectional radius. The present formulation is accurate and convenient, which not only shows deeper insight into the physical origins of a melting thermodynamic property response to perturbations but also provides guidance for the design and optimization of electronic nanodevices. [ABSTRACT FROM AUTHOR]

There have been major advances in the science to predict the likely environmental concentrations of nanomaterials, which is a key component of exposure and subsequent risk assessment. Considerable progress has been since the first Material Flow Analyses (MFAs) in 2008, which were based on very limited information, to more refined current tools that take into account engineered nanoparticle (ENP) size distribution, form, dynamic release, and better-informed release factors. These MFAs provide input for all environmental fate models (EFMs), that generate estimates of particle flows and concentrations in various environmental compartments. While MFA models provide valuable information on the magnitude of ENP release, they do not account for fate processes, such as homo- and heteroaggregation, transformations, dissolution, or corona formation. EFMs account for these processes in differing degrees. EFMs can be divided into multimedia compartment models (e.g., atmosphere, waterbodies and their sediments, soils in various landuses), of which there are currently a handful with varying degrees of complexity and process representation, and spatially-resolved watershed models which focus on the water and sediment compartments. Multimedia models have particular applications for considering predicted environmental concentrations (PECs) in particular regions, or for developing generic "fate factors" (i.e., overall persistence in a given compartment) for life-cycle assessment. Watershed models can track transport and eventual fate of emissions into a flowing river, from multiple sources along the waterway course, providing spatially and temporally resolved PECs. Both types of EFMs can be run with either continuous sources of emissions and environmental conditions, or with dynamic emissions (e.g., temporally varying for example as a new nanomaterial is introduced to the market, or with seasonal applications), to better understand the situations that may lead to peak PECs that are more likely to result in exceedance of a toxicological threshold. In addition, bioaccumulation models have been developed to predict the internal concentrations that may accumulate in exposed organisms, based on the PECs from EFMs. The main challenge for MFA and EFMs is a full validation against observed data. To date there have been no field studies that can provide the kind of dataset(s) needed for a true validation of the PECs. While EFMs have been evaluated against a few observations in a small number of locations, with results that indicate they are in the right order of magnitude, there is a great need for field data. Another major challenge is the input data for the MFAs, which depend on market data to estimate the production of ENPs. The current information has major gaps and large uncertainties. There is also a lack of robust analytical techniques for quantifying ENP properties in complex matrices; machine learning may be able to fill this gap. Nevertheless, there has been major progress in the tools for generating PECs. With the emergence of nano- and microplastics as a leading environmental concern, some EFMs have been adapted to these materials. However, caution is needed, since most nano- and microplastics are not engineered, therefore their characteristics are difficult to generalize, and there are new fate and transport processes to consider.

The photocatalytic activity of photocatalysts can be enhanced by cation doping, and the dopant concentration plays a key role in achieving high efficiency. This study explores the impact of copper (Cu) doping at concentrations ranging from 0% to 10% on the microstructural, optical, electronic, and photocatalytic properties of zinc oxide (ZnO) nanostructures. The x-ray diffraction analysis shows a non-linear alteration in the lattice parameters with increasing the Cu content and the formation of CuO as a secondary phase at the Cu concentration of >3%. Density functional theory calculations provide insights into the change in the electronic structures of ZnO induced by Cu doping, leading to the formation of localized d electronic levels above the valence band maximum. The modulation of the electronic structure of ZnO by Cu doping facilitates the visible light absorption via O 2p → Cu 3d and Cu 3d → Zn 2p transitions. Photoluminescence spectroscopy reveals a quenching of the defect-related emission peak at approximately 570 nm for all Cu-doped ZnO nanostructures, indicating a reduction in the structural and other defects. The photocatalytic activity tests confirm that the ZnO nanostructures doped with 3% Cu exhibit the highest efficiency compared to other samples due to the suitable band-edge position and visible light absorption. [ABSTRACT FROM AUTHOR]

Over the past few decades, chemical vapor deposition (CVD) of [2.2]paracyclophanes has captured significant attention as an emergent technology, producing conformal, chemically pure, and pinhole‐free coatings for biomedical and industrial applications. Compelling examples range from functional CVD polymers to tailored nanostructures. In this work, the unique functional properties of polymers derived from [2.2]paracyclophanes are connected with emergent applications. Special attention is given to the function‐property relationships in the areas of electronic materials, biomaterials, and separation materials. A particular focus is to highlight the versatility of CVD polymerization to process these polymers. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) Y 2 Zr 2 O 7 :Er/Yb tube-in-tube nanostructures were prepared via a simple electrospinning technique with a single nozzle. The diameter of the outer tube of the Y 2 Zr 2 O 7 :Er/Yb tube-in-tube nanostructures is 190–170 nm, the thickness of the outer wall is 22–20 nm, the diameter of the inner tube is 120–100 nm, and the wall thickness of the inner tube is 17–14 nm. The optical properties of the Y 2 Zr 2 O 7 :Er/Yb tube-in-tube nanostructures, including the up-conversion and downshifting luminescence spectra, temperature sensitivity, and thermochromic properties, were studied in detail. Under 980 nm excitation, two weak green emissions at 528 nm and 550 nm, as well as a strong red emission at 650 nm of Er ions, are presented. When excited at 378 nm, the Er ions exhibit strong green emission at 545 nm, two weak red emission peaks at 650 and 680 nm, and near-infrared emission peaks at 1400–1600 nm. With increasing environmental temperature, the luminescence color of the 1D Y 2 Zr 2 O 7 :Er/Yb tube-in-tube nanostructures exhibited a transition from "orange→yellow→ green" when excited at 980 nm. For the 1D Y 2 Zr 2 O 7 :xEr/yYb tube-in-tube nanostructures (x = 0.01, 0.02, 0.03; y = 0.05, 0.10, 0.15), the maximum values of S r are 2.3 % K−1 under 980 nm excitation and 2.1%K−1 under 378 nm excitation within the temperature range of 303–723 K. This work develops integrated multifunctional optical materials and provides an alternative approach for the fabrication of nanoscale smart platforms, advanced displays, and applications in information security. [ABSTRACT FROM AUTHOR]

The photocatalytic hydrolysis reaction primarily unfolds on the material's surface, making the material's morphology and microstructure critical for the catalytic efficiency of photocatalysts. In this paper, a formic acid-assisted melamine hydrothermal self-assembly method is explored to prepare g-C 3 N 4 photocatalysts with a unique morphology. The impact of sintering temperature on the morphology of the g-C 3 N 4 photocatalysts are explored and the effect of formic acid concentration on the XRD and FTIR was analyzed. Findings reveal that the g-C 3 N 4 nanostructures photocatalyst possesses fibrous tubular and nanosheet structures, boasting a heightened specific surface area (32.9 m2/g) and a more refined graphite-like crystalline framework. When synthesized with a 0.15 M concentration of formic acid, the g- C 3 N 4 nanostructured photocatalyst achieved a hydrogen production rate (1289.4 μmol h−1 g−1), which is approximately 4.8 times greater than that of bulk g-C 3 N 4 (264.7 μmol h−1 g−1). This work provides a simple method for preparing high-performance g-C 3 N 4 based photocatalysts for visible light hydrolysis hydrogen production. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Carbohelicenes have garnered considerable attention for their inherent chirality and structural flexibility. Increasing multi‐helicity and incorporating non‐six‐membered rings to substitute benzenoid rings within helicenes are effective strategies for introducing unique photoelectric properties. Despite the disclosure of numerous helicenes, the inaccessible precursors and the lack of synthetic routes pose a challenge in achieving desired helicene structures fused with non‐benzenoid rings. Herein, we report the synthesis of multiple non‐benzenoid carbohelicenes fused with fluorene unit(s) through intramolecular cyclodehydrogenation of 9,10‐di(naphthalen‐1‐ yl)anthracene on Au(111) surface. Two potential cyclodehydrogenation manners between naphthyl and anthracene lead to the formation of fluorene‐fused [5]helicene and [4]helicene moiety. Consequently, a total of four stable products were observed. The atomic topographies of products are characterized by bond‐resolving scanning tunneling microscopy. The chiral helicity of targeted products can be switched by tip manipulation. Density‐functional‐theory calculations unveils the reaction pathway of four products. The comparative analysis of their respective energy barriers exhibits a correlation with the experimentally determined yields. Furthermore, we synthesize the polymer chains incorporating non‐benzenoid carbohelicenes via the Ullmann reaction of 2,6‐dibromo‐9,10‐di(1‐naphthyl)anthracene precursors. Our work proposes a synthetic methodology for several novel helicene‐like structures fused with fluorene units and the polymer bearing helicene subunits, thus highlighting the immense potential of these compounds in the application fields of luminescent electronic devices. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Graphene nanoribbons (GNRs), which can be considered as a special type of conjugated polymers, are quasi‐one‐dimensional graphene cutouts with an opened band gap, revealing great potential as functional materials in optoelectronic, spintronic, and energy‐related applications. An effective strategy to modulate the properties of GNRs is doping heteroatoms into the π‐skeleton. Thanks to the bottom‐up synthetic approach, a number of heteroatom‐doped GNRs with precise structures have been reported, exhibiting intriguing properties. Nevertheless, a comprehensive summary of the progress of this field has remained elusive. In this review, we summarize the history and advances in bottom‐up synthesized heteroatom‐doped GNRs, including their synthetic routes, electronic properties, and promising applications. We hope to establish the reliable structure–property relationship, and provide guidance for the molecular design of heteroatom‐doped GNRs in the future. [ABSTRACT FROM AUTHOR]

In this study, modification of regular masks using composite nanofibers containing porous nanostructures has been considered in order to increase their efficiency in dealing with new threats. For this purpose, polystyrene was used as a low-cost polymer to prepare nanofibers and modify the surface of the respirator mask. ZIF-8 nanostructures with different sizes (14, 23, 65,144, and 265 nm) and zinc oxide nanoparticles, with an approximate size of 36 nm, were added to polymer nanofibers.2-methyl imidazole and Zn(NO3)2 were used to synthesize nanostructures. Two different methods (injection and stabilization) were used to incorporate nanostructures into fibers. The percentage of ZIF-8 and ZnO nanostructures were 0.5 and 2 wt% respects to polystyrene, respectively. Synthesis reactions and preparation of fibrous filters were carried out at ambient temperature. FESEM, FTIR, EDAX, TGA, and XRD techniques were used to identify the prepared nanoparticles and fibers. To evaluate the performance of the modified filters, their efficiency in removing suspended particles below 2.5 microns as well as CO2, SO2 and NO2 gases was surveyed. The results showed that ZIF nanoparticles with arbitrary sizes have been synthesized and successfully stabilized on the surface of nanofibers. Modifying the surface of the commercial mask by electrospinning method resulted in forming a fibrous layer with an approximate diameter of 700 nm and the presence of stabilized nanostructures in both methods was confirmed using FESEM images. Adding the nanofibers to the surface of the filter significantly increased their efficiency in removing suspended particles and toxic gases. The optimized modified filter contained ZIF-8 with14nm dimension and could remove sub-micron particles, CO2, NO2, and SO2 gases by 99, 91, 87, and 86%, respectively, making it as effective as commercially available N-95 masks. Moreover, it was observed that the incorporation of nanostructures by the stabilization method was more effective in improving the filtering efficiency of the fibrous mask. [ABSTRACT FROM AUTHOR]

In this study, a novel nanocomposite material consisting of Bi 2 O 3 and Bi 2 MoO 6 , named as Bi 2 O 3 @Bi 2 MoO 6 , was successfully fabricated by co-precipitation method in ethylene glycol solvent. Morphological analysis of the heat-treated sample at 400 °C for 12 h in Ar atmosphere (Bi 2 O 3 @Bi 2 MoO 6 _400 °C) showed that it contained nano-sized particles of Bi 2 O 3 and Bi 2 MoO 6 ; in addition, an amorphous phase along with a crystalline structure was also observed. When used as an anode for Li-ion batteries (LIBs), Bi 2 O 3 @Bi 2 MoO 6 _400 °C anode exhibits excellent electrochemical properties such as high Coulombic efficiency, high specific capacity, excellent capacity retention, and outstanding rate capacity. Specifically, the Bi 2 O 3 @Bi 2 MoO 6 _400 °C anode presented a reversible capacity of 786 mAh g−1 at the beginning cycle at 0.1 A g−1 and retained about 90 % of the charging capacity value after 80 cycles. The advanced electrochemical properties of the nanocomposite anode are related to the combination of many aspects such as nanostructure, existence of amorphous phase, and pseudo-behaviour of metal-based components. The structural stability and electrochemical performance of the anode material, therefore, are improved. These results demonstrate Bi 2 O 3 @Bi 2 MoO 6 _400 °C as a promising material for establishing high-performance LIB anodes. [Display omitted] • Bi 2 O 3 @Bi 2 MoO 6 powders are prepared by a facile method. • Bi 2 O 3 @Bi 2 MoO 6 powders contain amorphous and crystalline phases. • Bi 2 O 3 @Bi 2 MoO 6 materials possess nanostructures (from 20 nm to 50 nm). • Bi 2 O 3 @Bi 2 MoO 6 _400 °C anode displays high initial coulombic efficiency (>80 %). • Bi 2 O 3 @Bi 2 MoO 6 _400 °C anode shows a reversible capacity of 701 mAh g−1 after 80 cycles. [ABSTRACT FROM AUTHOR]

The widespread problem of water pollution is jeopardizing our health. Elimination of dye pollution from the solvent phase by adsorption is a necessary aspect of research. In this research, CuMn2O4/CuMnO nanocomposites were prepared via the co-precipitation method and used to remove dye pollution from an aqueous solution. These nanocomposites were synthesized for the first time in this work. The techniques including XRD, SEM, EDS, VSM, FT-IR, and UV–Vis were used to identify the nanocomposites. The nanocomposites showed a ferromagnetic behavior (coercivity ~ 1082.55 Oe) in low fields and an antiferromagnetic behavior in high fields. Also, their photocatalytic properties for eriochrome black T degradation were studied under visible light irradiation, for the first time. The experiments were repeated in the presence of sucrose as a capping agent. The structure, morphology, and photocatalytic properties of two samples prepared in the presence and absence of a capping agent for eriochrome black T degradation were investigated and compared. The results showed that the sample prepared in the absence of a capping agent has better morphology and photocatalytic activity for the removal of eriochrome black T from an aqueous solution. The photodegradation amount of eriochrome black T solution with 10 ppm concentration by 0.03 g nanocomposite was obtained 76%. The eriochrome black T degradation at acidic pH occurred at a higher rate (80.45% after 90 min) than that at other pHs. [ABSTRACT FROM AUTHOR]

Crystallization fouling, a process where mineral scales form on surfaces, is of broad importance in nature and technology, negatively impacting water treatment and electricity production. However, a rational methodology for designing materials with intrinsic resistance to scaling and scale adhesion remains elusive. Here, guided by nucleation physics, this work investigates the effect of coating composition and surface structure on the nucleation and growth mechanism of scale on metallic heat transfer surfaces nanoengineered by large‐area techniques. This work observes that on hydrophilic nanostructured copper, despite its significantly enlarged surface area compared to smooth surfaces, scale formation is substantially suppressed leading to sustained, efficient cooling performance. This work reveals the mechanism through thermofluidic modeling coupled with in situ optical characterization and show that surface bubble formation through degassing is responsible for generating local hot spots enhancing supersaturation. This work then demonstrates a scalephobic nanostructured surface which reduces the accumulated surface scale mass 3.5× and maintains an 82% higher heat transfer coefficient compared to superhydrophobic surfaces with corresponding energy conversion savings. This work not only advances the understanding of fouling mechanisms but also holds promise for practical applications in industries reliant on efficient heat transfer processes. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Graphene nanoribbons (GNRs), which can be considered as a special type of conjugated polymers, are quasi‐one‐dimensional graphene cutouts with an opened band gap, revealing great potential as functional materials in optoelectronic, spintronic, and energy‐related applications. An effective strategy to modulate the properties of GNRs is doping heteroatoms into the π‐skeleton. Thanks to the bottom‐up synthetic approach, a number of heteroatom‐doped GNRs with precise structures have been reported, exhibiting intriguing properties. Nevertheless, a comprehensive summary of the progress of this field has remained elusive. In this review, we summarize the history and advances in bottom‐up synthesized heteroatom‐doped GNRs, including their synthetic routes, electronic properties, and promising applications. We hope to establish the reliable structure–property relationship, and provide guidance for the molecular design of heteroatom‐doped GNRs in the future. [ABSTRACT FROM AUTHOR]

The development of low‐cost and high‐efficiency oxygen evolution reaction (OER) photoelectrocatalysts is a key requirement for H2 generation via solar‐assisted water splitting. In this study, we report on an amenable fabrication route to carbon cloth‐supported graphitic carbon nitride (gCN) nanoarchitectures, featuring a modular dispersion of NiO as co‐catalyst. The synergistic interaction between gCN and NiO, along with the tailoring of their size and spatial distribution, yield very attractive OER performances and durability in freshwater splitting, of great significance for practical end‐uses. The potential of gCN electrocatalysts containing ultra‐dispersed, i. e. "quasi‐atomic" NiO, exhibiting a higher activity than the ones containing nickel oxide nanoaggregates, is further highlighted by their activity even in real seawater. This work suggests that efficient OER catalysts can be designed through the construction of optimized interfaces between transition metal oxides and carbon nitride, yielding inexpensive and promising noble metal‐free systems for real‐world applications. [ABSTRACT FROM AUTHOR]

This essay presents the viewpoint of the author on the topic of chirality and optical activity in nanostructures. It particularly focuses on the interaction of chiral molecules with plasmonic and excitonic nanocrystals and on induction of circular dichroism in such achiral nanocrystals. It discusses recent developments in the shape symmetry breaking of achiral metal nanostructures using photochemical processes induced by asymmetric localized plasmonic hot spots excited through circularly polarized light illumination. Finally, it addresses symmetry breaking in intrinsically chiral inorganic nanocrystals using chiral ligands during their formation, leading to 100 % enantiomeric excess in the nanocrystals of TbPO4⋅H2O. These nanocrystals exhibit an interesting nucleation mechanism, which leads to very high chiral amplification (secondary nucleation). [ABSTRACT FROM AUTHOR]

Metallic nanostructures hold immense promise for radiative heating technology because of their distinctive capability to simultaneously achieve high mid‐infrared reflectance and generate vibrant colors through structural or plasmonic effects. However, fabricating metallic nanostructures remains challenging using traditional top–down techniques. Here, the solid‐state superionic stamping (S4) process is demonstrated as a scalable and economical tool to electrochemically imprint metallic grid nano‐patterns onto flexible substrates. With precise control over grid width and length at the nanoscale, the S4 approach enables the fabrication of nano‐patterned grid coatings exhibiting a spectrum of colors. These coatings also show high mid‐infrared reflectance exceeding 80% at 9.5 µm, leading to radiative heating effects of 5.9 and 3.1 °C compared to bare skin and cotton, respectively. This work introduces a viable strategy for creating colored infrared‐reflective patterns, paving the way for diverse thermal management applications. [ABSTRACT FROM AUTHOR]

Layered CoO2 is of great interest for its promising properties but is meta‐stable in its bulk form. CoO2 is synthesized by converting the quasi‐1D crystal structure of bulk Ca3Co2O6 via a hydrothermal treatment. The resulting nanostructures are predominantly nanoscrolls with very thin walls, which exhibit long‐term stability. A detailed structural investigation reveals that the CoO2 is found to crystallize in monoclinic form, similar to the related CaCoO2‐CoO2 misfit structure. Individual nanoscrolls are characterized electrically and show a p‐type semiconducting nature with a high current‐carrying capacity of 4·105 A cm−2 and an extremely high breakdown voltage of up to 270 kV cm−1. The results demonstrate the possibility to stabilize meta‐stable materials in low‐dimensional forms and a promising application of the nanoscrolls as interconnect in high‐voltage electronic circuitry. [ABSTRACT FROM AUTHOR]

Electrohydrodynamic (EHD) printing has critical merits in micro/nanoscale additive manufacturing because of its ultrahigh resolution and wide ink compatibility, making it an advantageous choice for electronics manufacturing, high-resolution prototyping, and biological component fabrication. However, EHD printing is currently limited by its rather low throughput due to the lack of high-frequency and high-density multi-nozzle printheads. This paper presents a novel EHD printhead with a protruding polymer-based nozzle design. An insulated, hydrophobic, and protruding polymer nozzle array with an appropriate geometric structure can effectively address key problems in multi-nozzle jetting, such as electrical crosstalk, electrical discharge, liquid flooding, and nonuniform jetting. By investigating the influence of the electrical and geometric characteristics of the nozzle arrays on the electrical crosstalk behavior and fabricating the optimized nozzle array via MEMS technology, we achieve an EHD printhead with a large scale (256), high density (127 dpi), and high jetting frequency (23 kHz), and addressable jetting can be realized by adding independently controllable extractors underneath the nozzle array. Many functional materials, such as quantum dots, perovskite, and nanosilver inks, can be ejected into high-resolution patterns through the optimized nozzle array, demonstrating the great prospects of our designed printhead in electronics manufacturing. This MEMS-compatible printhead design lays the foundation for high-throughput fabrication of micro/nanostructures and promotes practical applications of EHD printing in functional electronics and biomedical/energy devices. [ABSTRACT FROM AUTHOR]

Miniaturization of organic afterglow materials has shown promising application in biomedical and other areas. Current technologies, such as nanoprecipitation, mechanical treatment, and emulsion polymerization, lack the capability of facile control on the morphology and dimension of the miniaturized organic afterglow materials. Here we report the fabrication of organic afterglow nanostructures via block copolymer self‐assembly at room temperature. The fabrication is based on two‐component design strategy where hydrophobic luminescent emitters with small rate constants of phosphorescence decay or reverse intersystem crossing are designed as the first component. Amphiphilic block copolymers that can form spherical core‐shell micelles and worm‐like micelles with glassy hydrophobic cores are used as the second component. Upon addition of water into a dimethylformamide solution that contains the two components, the amphiphilic block copolymers self‐assemble into well‐defined nanostructures and accommodate the hydrophobic luminescent emitters in nanostructure's hydrophobic cores. After switching to pure water by dialysis, room‐temperature afterglow nanostructures have been obtained because of the excellent protection of organic triplets by the glassy hydrophobic cores. The afterglow nanostructures exhibit intriguing afterglow mechanism modulated by the types of luminescent emitters, controlled dimensions and morphologies by the structural parameters of the block copolymers. [ABSTRACT FROM AUTHOR]

In the design of optical devices and components, geometric structures and optical properties of materials, such as absorption, refraction, reflection, diffraction, scattering, and trapping, have been utilized. Finding the ideal material with certain optical and geometric characteristics is essential for a customized application. Herein, unoxidizable achromatic copper films (ACFs) are fabricated on Al2O3 substrates utilizing an atomic sputtering epitaxy apparatus. ACFs are made up of two regions vertically: a comparatively flat layer region and a 3D porous nanostructured region on top of the flat region. The measured specular reflectance displays low‐pass filter behavior with a sharp cutoff frequency in the infrared spectrum. Furthermore, the measured diffusive reflectance spectra show light‐trapping behavior in the spectral region above the cutoff frequency, where there are no known absorption mechanisms, such as phonons and interband transitions. A focused ion beam scanning electron microscope is utilized to study the thin film's nanostructured region through 3D tomographic analysis in order to comprehend the phenomena that are observed. This work will shed fresh light on the design and optimization of optical filters and light‐trapping employing porous nanostructured metallic thin films. [ABSTRACT FROM AUTHOR]

3D nanolithography based on two‐photon polymerization (TPP) allows for the high‐precision fabrication of nearly arbitrary 3D micro/nanostructures, finding extensive applications in areas such as micro‐optics, micro‐mechanics, and biomedicine. However, the large size, complexity of optical systems, and high costs have significantly constrained the widespread adoption of 3D nanolithography technology in both scientific research and industry. In this study, a metasurface is introduced, for the first time, into 3D nanolithography resulting in the construction of a miniaturized and simplified TPP system that achieved efficient multi‐focus parallel processing with high uniformity. A microlens array is fabricated, showcasing the system's application capacity to generate an array of devices with high consistency and quality. It is believed that the utilization of metasurface devices will provide a novel TPP operating platform, enabling richer and more flexible printing functionalities while maintaining system miniaturization and low cost. [ABSTRACT FROM AUTHOR]

Water-in-oil microemulsions, as stable colloidal dispersions from quasi-ternary mixtures, have been used in diverse applications, including nanoreactors for confined chemical processes. Their use as soft templates not only includes nanomaterial synthesis but also the interfacial assembly of nanoparticles in hybrid nanostructures. Especially the hierarchical arrangement of different types of nanoparticles over a surface in filament networks constitutes an interesting bottom-up strategy for facile and tunable film coating. Herein, we demonstrate the versatility of this surface assembly from microemulsion dispersions. Transmission and Scanning Electron Microscopy, in addition to UV–Vis Transmittance Spectroscopy, proved the assembly tunability after solvent evaporation under different conditions: the nanostructured films can be formed over different surfaces, using different compositions of liquid phases, as well as with the incorporation of different nanoparticle materials while keeping equivalent surface functionalization. This offers the possibility of adapting different components and conditions for coating tuning on a larger scale with simple procedures. [ABSTRACT FROM AUTHOR]

This Special Issue on "Current Advances in Nanoelectronics, Nanosensors, and Devices" collects cutting-edge research and comprehensive reviews in the rapidly evolving field of nanotechnology. This collection aims to highlight key breakthroughs in nanostructures, 2D materials, and their applications in nanoelectronics, nanosensors, and emerging device technologies. [ABSTRACT FROM AUTHOR]

Innovative methods for substrate patterning provide intriguing possibilities for the development of devices based on ordered arrays of semiconductor nanowires. Control over the nanostructures' morphology in situ can be obtained via extensive theoretical studies of their formation. In this paper, we carry out an investigation of the ordered nanowires' formation kinetics depending on the growth mask geometry. Diffusion equations for the growth species on both substrate and nanowire sidewalls depending on the spacing arrangement of the nanostructures and deposition rate are considered. The value of the pitch corresponding to the maximum diffusion flux from the substrate is obtained. The latter is assumed to be the optimum in terms of the nanowire elongation rate. Further study of the adatom kinetics demonstrates that the temporal dependence of a nanowire's length is strongly affected by the ratio of the adatom's diffusion length on the substrate and sidewalls, providing insights into the proper choice of a growth wafer. The developed model allows for customization of the growth protocols and estimation of the important diffusion parameters of the growth species. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS) is a powerful tool and an up-to-date method of analytical chemistry due to its high sensitivity and fingerprint recognition capabilities. Nowadays SERS due to its label-free detection capabilities is being actively developed in medical fields, for example in the analysis of biologically important substances in different matrixes, for potential on-site detection of toxic substances, food safety, and so on. To get the SERS signal, it is necessary the presence of plasmonic nanostructures in the SERS substrates. Electrospun nanofibers have been an attractive alternative to SERS-platforms due to the diversity of advantages, including ease of preparation, structure flexibility, and others. In this review, we summarized the methods of plasmonic nanostructures incorporating substrate based on electrospun nanofibers. Also, the analytical application of SERS-active electrospun nanofibers with embedded nanostructures focused on biologically significant molecules is observed in detail. Finally, the future outlook in the application of these substrates in bioanalysis as the most promising area in analytical chemistry is presented. [ABSTRACT FROM AUTHOR]

Introduction: In this study, the effects of adding titanium dioxide nanotubes (TiO2) to 3D‐printed denture base resin on the mechanical and physical properties of denture bases were examined for the first time. Methods: The specimens were digitally created using 3D builder software from Microsoft Corporation through computer‐aided design. In accordance with the test specifications for transverse strength, impact strength, hardness, surface roughness, and color stability, specimens were designed and printed with certain dimensions following relevant standards. TiO2 nanotubes (diameter: 15–30 nm and length: 2–3 μm) were added to the 3D‐printed denture base resin (DentaBase, Asiga, Australia) at 1.0% and 1.5% by weight. Flexural strength, impact strength (Charpy impact), hardness, surface roughness, and color stability were evaluated, and the collected data were analyzed with ANOVA followed by Tukey's post hoc test (α = 0.05). Field emission scanning electron microscopy (FESEM) and energy dispersive x‐ray spectroscopy (EDX) mapping were used to evaluate the dispersion of the nanotubes. Results: Compared with those of the control group (0.0 wt.% TiO2 nanotubes), the average flexural, impact, and hardness values of the 1.0 and 1.5 wt.% TiO2 nanotube reinforcement groups increased significantly. Both nanocomposite groups showed significant color changes compared to that of the pure resin, and there was a considerable reduction in the surface roughness of the nanocomposites compared to that of the control group. Conclusion: Adding TiO2 nanotubes to 3D‐printed denture base materials at 1.0 and 1.5 wt.% could enhance the mechanical and physical properties of the material, leading to better clinical performance. Clinical Significance: In terms of clinical applications, 3D‐printed denture base material has been shown to be a viable substitute for traditional heat‐cured materials. By combining this with nanotechnology, existing dentures could be significantly enhanced, promoting extended service life and patient satisfaction while addressing the shortcomings of the current standard materials. [ABSTRACT FROM AUTHOR]

Functional triblock copolymers (BCPs), i.e., poly(glycidyl methacrylate/methyl methacrylate)-b-poly(lauryl methacrylate)-b-poly(glycidyl methacrylate/methyl methacrylate) triblock copolymers [(P(GMA/MMA)-b-PLMA-b-P(GMA/MMA)], were investigated as toughening modifiers for all-methacrylate polymer blends. Methyl methacrylate (MMA) was copolymerized with methacrylic acid (MAA) in the presence of the BCPs. Without MAA in the polymethacrylate matrices, the BCP blends formed micron-scale phase structures by polymerization-induced phase separation. In matrices copolymerized with MAA, self-assembled nanostructures, such as curved lamellae, worm-like cylindrical micelles, or spherical micelles were formed. The BCP blends with worm-like cylindrical nano-micelles achieved much higher fracture toughness than those with spherical nano-micelles. The toughening mechanisms were elucidated by transmission electron microscopy. Cavitation was initiated in worm-like cylindrical nano-micelles, and the aligned cavitation formed craze-like deformation with increased loads. This relieves hydrostatic tensile stress in front of the crack tip, forming a large shear yield zone within the craze-like deformation region, contributing to high toughness. [ABSTRACT FROM AUTHOR]

We propose an in situ gas etching-thermal assembly strategy to simultaneously create mesopore-dominated carbon cores with ultrathin carbon-layer shells fully decorated with highly dispersed Mn-N 4 single-atom sites, which was used as a highly active and stable ORR catalyst in zinc-air batteries. [Display omitted] Applications of zinc-air batteries are partially limited by the slow kinetics of oxygen reduction reaction (ORR); Thus, developing effective strategies to address the compatibility issue between performance and stability is crucial, yet it remains a significant challenge. Here, we propose an in situ gas etching-thermal assembly strategy with an in situ -grown graphene-like shell that will favor Mn anchoring. Gas etching allows for the simultaneous creation of mesopore-dominated carbon cores and ultrathin carbon layer shells adorned entirely with highly dispersed Mn-N 4 single-atom sites. This approach effectively resolves the compatibility issue between activity and stability in a single step. The unique core–shell structure allows for the full exposure of active sites and effectively prevents the agglomerations and dissolution of Mn-N 4 sites in cores. The corresponding half-wave potential for ORR is up to 0.875 V (vs. reversible hydrogen electrode (RHE)) in 0.1 M KOH. The gained catalyst (Mn-N@Gra-L)-assembled zinc-air battery has a high peak power density (242 mW cm−2) and a durability of ∼ 115 h. Furthermore, replacing the zinc anode achieved a stable cyclic discharge platform of ∼ 20 h at varying current densities. Forming more fully exposed and stable existing Mn-N 4 sites is a governing factor for improving the electrocatalytic ORR activity, significantly cycling durability, and reversibility of zinc-air batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] The construction of binder-free electrodes with well-defined three-dimensional (3D) morphology and optimized electronic structure represents an efficient strategy for the design of high-performance electrocatalysts for the development of efficient green hydrogen technologies. Herein, Ru nanocrystals were modified on 3D interconnected porous FeOOH nanostructures with open network-like frameworks on NiFe foam (Ru/FeOOH@NFF), which were used as an efficient electrocatalyst. In this study, a 3D interconnected porous FeOOH with an open network structure was first electrodeposited on NiFe foam and served as the support for the in-situ modification of Ru nanocrystals. Subsequently, the Ru nanocrystals and abundant oxygen vacancies were simultaneously incorporated into the FeOOH matrix via the adsorption-reduction method, which involved NaBH 4 reduction. The Ru/FeOOH@NFF electrocatalyst shows a large specific surface area, abundant oxygen vacancies, and modulated electronic structure, which collectively result in a significant enhancement of catalytic properties with respect to the oxygen evolution reaction (OER) and urea oxidation reaction (UOR). The Ru/FeOOH@NFF catalyst exhibits an outstanding OER performance, requiring a low overpotential (360 mV) at 200 mA cm−2 with a small Tafel slope (58 mV dec-1). Meanwhile, the Ru/FeOOH@NFF catalyst demonstrates more efficient UOR activity for achieving 200 mA cm−2 at a lower overpotential of 272 mV. Furthermore, an overall urea electrolysis cell using the Ru/FeOOH@NFF as the anode and Pt as the cathode (Ru/FeOOH@NFF||Pt) reveals a cell voltage of 1.478 V at 10 mA cm−2 and a prominent durability (120 h at 50 mA cm−2). This work will provide a valuable understanding of the construction of high-performance electrocatalysts with 3D microstructure for promoting urea-assisted water electrolysis. [ABSTRACT FROM AUTHOR]

The technological requirements of low-power and high-fidelity color displays have been instrumental in driving research into advanced coloration technologies. At the forefront of these developments is the implementation of dye-free approaches, which overcome previous constraints related to color resolution and fading. Resonant dielectric nanostructures have emerged as a promising paradigm, showing great potential for high efficiency, high color saturation, wide gamut palette, and image reproduction. However, they still face limitations related to color accuracy, purity, and simultaneous brightness tunability. Here, we demonstrate an all-dielectric metasurface empowered by photonic bound states in the continuum (BICs), which supports sharp resonances throughout the visible spectral range, ideally suited for producing a wide range of structural colors. The metasurface design consists of TiO2 ellipses with carefully controlled sizes and geometrical asymmetry, allowing versatile and on-demand variation of the brightness and hue of the output colors, respectively. [ABSTRACT FROM AUTHOR]

The intricate nanostructured surface of black silicon (BSi) has advanced photodetector technology by enhancing light absorption. Herein, we delve into the latest advancements in BSi surface modification techniques, specifically focusing on their profound impact on light trapping and resultant photodetector performance improvement. Established methods such as metal-assisted chemical etching, electrochemical etching, reactive ion etching, plasma etching, and laser ablation are comprehensively analyzed, delving into their mechanisms and highlighting their respective advantages and limitations. We also explore the impact of BSi on the emerging applications in silicon (Si)-based photodetectors, showcasing their potential for pushing the boundaries of light-trapping efficiency. Throughout this review, we critically evaluate the trade-offs between fabrication complexity and performance enhancement, providing valuable insights for future development in this rapidly evolving field. This knowledge on the BSi surface modification and its applications in photodetectors can play a crucial role in future implementations to substantially boost light trapping and the performance of Si-based optical detection devices consequently. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting is an environmentally friendly hydrogen production method that uses abundant renewable resources such as water and sunlight. While Titanium dioxide (TiO2) photocatalyst exhibits excellent properties, its high band gap limits absorption to ultraviolet (UV) irradiation, resulting in low photo conversion efficiency. This review explores various modification techniques aimed at enhancing the efficiency of TiO2 under visible light irradiation. Factors influencing the photocatalytic water splitting reaction, such as catalyst structure, morphology, band gap, sacrificial reagents, light intensity, temperature, and potential of Hydrogen (pH) are examined. This review also summarizes different catalyst synthesis methods, and types of photocatalytic reactors, and provides insights into quantum yield. Finally, the review addresses the challenges and future outlook of photocatalytic water splitting. [ABSTRACT FROM AUTHOR]