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The thermal anisotropy of materials holds significant theoretical and practical implications in the domains of thermal transport and thermoelectricity. Black phosphorene, a novel two-dimensional (2D) semiconductor, is notable for its exceptional chemical and physical properties, attracting substantial attention for its thermal transport characteristics. Similar to other 2D materials, black phosphorene exhibits pronounced in-plane thermal anisotropy. Given its expanding applications in nanoelectronics, optoelectronics, and thermoelectrics, there is a growing need to manipulate its anisotropic thermal transport. Current methods for adjusting anisotropy or isotropy typically involve structural engineering or materials processing, which are often costly, time-consuming, and irreversible. In contrast, little progress has been made with methods that are intact, robust, and reversible. Driven by the intrinsic relationship between interatomic interaction-mediated phonon transport and electronic charges, we conduct a comprehensive investigation into the impact of an external electric field on the thermal transport properties of 2D black phosphorene using first-principles calculations and the phonon Boltzmann transport equation. Our findings reveal that applying an electric field in the Zigzag direction reduces the lattice thermal conductivity of black phosphorene, with the Zigzag direction being more responsive to the electric field than the Armchair direction. By adjusting the electric field to a maximum of E(f_xx) = 0.2 V Å−1, the anisotropic thermal conductivity of black phosphorene decreases by more than 28%, demonstrating effective manipulation of anisotropy. This significant transition in anisotropic thermal transport arises from the substantial reduction in thermal conductivity along the Zigzag direction at moderate electric field strengths. The underlying cause of this variation in anisotropy can be attributed to changes in group velocity, with the phonon lifetime serving as a scaling factor for reducing anisotropy. Analysis of the electronic structures shows that stronger electric fields induce more charges, enhancing the screening effect. The electric field significantly alters thermal conductivity by affecting bond ionicity and anharmonicity. Our study introduces a robust approach for tuning the anisotropy of phonon transport in materials using an external electric field, without altering the atomic structure, thus offering considerable advantages for applications in nanoelectronics and thermoelectric energy conversion. [ABSTRACT FROM AUTHOR]

Second harmonic generation is a non-linear optical phenomenon in which coherent radiation with frequency ω interacts with a non-centrosymmetric material and produces coherent radiation at frequency 2ω. Owing to the exciting physical phenomena that take place during the non-linear optical excitation at the nanoscale, there is currently extensive research in the non-linear optical responses of nanomaterials, particularly in low-dimensional materials. Here, we review recent advancements in the polarization-resolved second harmonic generation propertied from atomically thin two-dimensional (2D) crystals and present a unified theoretical framework to account for their nonlinear optical response. Two major classes of 2D materials are particularly investigated, namely metal chalcogenides and perovskites. The first attempts to tune and control the second harmonic generation properties of such materials via the application of specific nanophotonic schemes are additionally demonstrated and discussed. Besides presenting recent advances in the field, this work also delineates existing limitations and highlights emerging possibilities and future prospects in this field. [ABSTRACT FROM AUTHOR]

The advancement of economical and readily available electrocatalysts for the oxygen reduction reaction (ORR) holds paramount importance in the advancement of fuel cells and metal‐air batteries. Recently, 2D non‐metallic materials have obtained substantial attention as viable alternatives for ORR catalysts due to their manifold advantages, encompassing low cost, ample availability, substantial surface‐to‐volume ratio, high conductivity, exceptional durability, and competitive activity. The augmented ORR performances observed in metal‐free 2D materials typically arise from heteroatom doping, defects, or the formation of heterostructures. Here, the authors delve into the realm of electrocatalysts for the ORR, pivoting around metal‐free 2D materials. Initially, the merits of metal‐free 2D materials are explored and the reaction mechanism of the ORR is dissected. Subsequently, a comprehensive survey of diverse metal‐free 2D materials is presented, tracing their evolutionary journey from fundamental concepts to pragmatic applications in the context of ORR. Substantial importance is given on the exploration of various strategies for enhancing metal‐free 2D materials and assessing their impact on inherent material performance, including electronic properties. Finally, the challenges and future prospects that lie ahead for metal‐free 2D materials are underscored, as they aspire to serve as efficient ORR electrocatalysts. [ABSTRACT FROM AUTHOR]

III-V lasers based on self-assembled quantum dots (QDs) have attracted widespread interest due to their unique characteristics, including low threshold current density (Jth), low sensitivity to backreflections, and resistance to threading dislocations. While most work to date has focused on 1.3 μm InAs/GaAs QDs, InP QDs have also aroused interest in lasers emitting at visible wavelengths. Molecular beam epitaxy (MBE) enables the growth of high-density InP/AlGaInP QDs on exact (001)-oriented GaAs substrates but requires a relatively low substrate temperature of <500 °C. The low substrate temperature used for phosphide growth in MBE leads to degraded optical properties and makes post-growth annealing a crucial step to improve the optical quality. Here, we report the exceptional thermal stability of InP/AlGaInP QDs grown using MBE, with up to 50× improvement in room temperature photoluminescence intensity with the optimization of annealing temperature and time. We also demonstrate the room temperature pulsed operation of InP multiple quantum dot (MQD) lasers on GaAs (001) emitting close to 735 nm with Jth values of 499 A/cm2 after annealing, a factor of 6 lower than their as-grown counterparts and comparable to such devices grown by MOCVD. In0.6Ga0.4P single quantum well (SQW) lasers on GaAs (001) also exhibit a substantial reduction in Jth from 340 A/cm2 as-grown to 200 A/cm2 after annealing, emitting at 680 nm under pulsed operation conditions. This work shows that post-growth annealing is essential for realizing record-performance phosphide lasers on GaAs grown by MBE for applications in visible photonics. [ABSTRACT FROM AUTHOR]

Protein phosphorylation is one of the most common mechanisms regulating cellular signaling pathways, and many kinases and phosphatases are proven drug targets. Upon phosphorylation, protein functions can be further regulated by the distinct isomerase Pin1 through cis-trans isomerization. Numerous protein targets and many important roles have now been elucidated for Pin1. However, no tools are available to detect or target cis and trans conformation events in cells. The development of Pin1 inhibitors and stereo- and phospho-specific antibodies has revealed that cis and trans conformations have distinct and often opposing cellular functions. Aberrant conformational changes due to the dysregulation of Pin1 can drive pathogenesis but can be effectively targeted in age-related diseases, including cancers and neurodegenerative disorders. Here, we review advances in understanding the roles of Pin1 signaling in health and disease and highlight conformational regulation as a distinct signal transduction checkpoint in disease development and treatment. [ABSTRACT FROM AUTHOR]

Time-zero is of considerable significance for determining both deformational and mechanical properties of high-performance concrete from very early ages. In this paper, four methods for determining the time-zero are investigated comparably, including stress evolution measurement, autogenous strain method, ultrasonic testing, and temperature rate method. A critical review of the theoretical basis behind each method is presented, with emphasis on the applicability and limitations of each method. Based on a case study, the practical capabilities of all four methods for determining the time-zero of high-performance concrete with a water-binder ratio (w/b) of 0.25 are experimentally assessed. It is found that the ultrasonic testing and temperature rate methods are better suited due to their simplicity and availability compared to the other two methods. Besides, the temperature of cement-based composites at very early ages can affect the determined values of time-zero, which needs further research. [ABSTRACT FROM AUTHOR]

After the discovery of graphene in 2004, the field of atomically thin crystals has exploded with the discovery of thousands of 2-dimensional materials (2DMs) with unique electronic and optical properties, by making them very attractive for a broad range of applications, from electronics to energy storage and harvesting, and from sensing to biomedical applications. In order to integrate 2DMs into practical applications, it is crucial to develop mass scalable techniques providing crystals of high quality and in large yield. Electrochemical exfoliation is one of the most promising methods for producing 2DMs, as it enables quick and large-scale production of solution processable nanosheets with a thickness well below 10 layers and lateral size above 1 μm. Originally, this technique was developed for the production of graphene; however, in the last few years, this approach has been successfully extended to other 2DMs, such as transition metal dichalcogenides, black phosphorous, hexagonal boron nitride, MXenes and many other emerging 2D materials. This review first provides an introduction to the fundamentals of electrochemical exfoliation and then it discusses the production of each class of 2DMs, by introducing their properties and giving examples of applications. Finally, a summary and perspective are given to address some of the challenges in this research area. [ABSTRACT FROM AUTHOR]

In recent years, anisotropic 2D materials (black phosphorus, ReS2, WTe2, etc.) have garnered significant attention due to their orientation‐dependent physical and chemical properties, along with their potential applications in micro‐nano device development, such as crystal‐based diodes, polarized light photodetectors, and directional heat transfer. As a practical, quick, and nondestructive characterization tool, Raman spectroscopy, with its unique and unmatched advantages in studying anisotropic materials, plays a crucial role. It enables lattice orientation identification, investigation of structural phase transitions, and examination of anisotropic lattice vibrations, among other aspects. Here, a comprehensive review of recent developments in Raman spectroscopy research on anisotropic materials is provided. To begin, this study introduces the classification of anisotropic materials before delving into the polarized Raman spectroscopy principle. Various research directions of Raman spectroscopy in anisotropic materials are explored, including lattice orientation identification, temperature dependence, interlayer coupling, electron–phonon interaction, thickness dependence, and high‐pressure phase transition. Finally, potential future directions in the field of Raman spectroscopy for anisotropic materials are discussed, and the potential challenges that may arise are addressed. [ABSTRACT FROM AUTHOR]

Marked differences in survival from melanoma are noted between men and women that cannot be accounted for by behavioral differences. We and others have provided evidence that this difference may be due to increased expression of immune-related genes from the second X chromosome because of failure of X inactivation. In the present review, we have examined evidence for the contrary view that survival differences are due to weaker immune responses in males. One reason for this may be the loss of Y chromosomes (LOY), particularly in older males. The genes involved may have direct roles in immune responses or be noncoding RNAs that regulate both sex and autosomal genes involved in immune responses or tumor growth. Loss of the KDM6C and KDM5D demethylases appeared to common genes involved. The second factor appears to be the activation of androgen receptors (AR) on melanoma cells that increase their invasiveness and growth. Induction of T-cell exhaustion by AR that limits immune responses against melanoma appeared a common finding. The development of treatments to overcome effects related to gene loss on Y poses challenges, but several avenues related to AR signaling appear worthy of further study in the treatment of metastatic disease., (© 2024 The Author(s). Pigment Cell & Melanoma Research published by John Wiley & Sons Ltd.)

The past decades have witnessed significant advancements in the growth of two-dimensional (2D) materials, offering a wide range of potential applications in the fields of electronics, optoelectronics, energy storage, sensors, catalysis, and biomedical treatments. Epitaxial heterostructures based on 2D materials, including vertical heterostructures, lateral structures, and superlattices, have emerged as novel material systems to manipulate the intrinsic properties and unlock new functionalities. Therefore, the development of controllable preparation methods for tailored epitaxial heterostructures serves as a fundamental basis for extensive property investigation and further application exploration. However, this pursuit presents formidable challenges due to the incomplete understanding of growth mechanisms and limited designable strategies. Chemical vapor deposition (CVD) is deemed as a promising and versatile platform for the controlled synthesis of 2D materials, especially with regard to achieving lattice matching, a critical factor in epitaxial growth. Consequently, CVD holds potential to overcome these hurdles. In this Feature Article, we present our recent breakthroughs in the controllable preparation of 2D epitaxial heterostructures using CVD. Our focus revolves around the processes of morphology engineering, interface engineering, size and density engineering, and striking the delicate balance between growth and etching. Using molten metals or alloys as primary catalysts, we have achieved remarkable control over the fabrication of graphene/hexagonal boron nitride (hBN) super-ordered arrays, enabled multistage etching of graphene/hBN heterostructures, and successfully realized the construction of graphene/MXene heterostructures. Furthermore, our research endeavors encompass both bottom-up and top-down fabrication methods, offering a novel perspective on the synthesis of 2D epitaxial heterostructures. The resulting products hold immense potential for enhancing the efficiency of critical reactions such as oxygen reduction, CO2 reduction, and hydrogen evolution reactions. By presenting our methodologies for obtaining 2D epitaxial heterostructures through CVD, we aspire to inspire fellow researchers in this field to devise more feasible and controllable fabrication techniques while also fostering the exploration of diverse heterostructure configurations. Together, these advancements will undoubtedly pave the way for further breakthroughs in atomic manufacturing and novel applications. [ABSTRACT FROM AUTHOR]

Lightweight mortars are indicated for services that require low specific mass composites. There are several lightweight aggregates available on the market. Waste rubber from tires is a low-density waste option that can be used as lightweight aggregate. The rubber waste when used in mortar reduces its density, in addition to bringing benefits from an environmental point of view. In this research, the mechanical behavior, and physical properties of mortars in which the natural fine aggregate contents were replaced by mixtures in different proportions of rubber, expanded vermiculite, and expanded clay were investigated. For the analysis of the properties of the composites, they were submitted to tests of dynamic modulus of elasticity, damping, compressive strength, flexural strength, coefficient of capillarity, density, and determination of ultrasonic wave transmission velocity. All tested mortars met the requirements of the Brazilian standard, being indicated for laying and covering walls and ceilings, in addition to having excellent acoustic and damping performance. [ABSTRACT FROM AUTHOR]

The polymorphism of phosphorus-based materials has garnered much research interest, and the variable chemical bonding structures give rise to a variety of micro and nanostructures. Among the different types of materials containing phosphorus, elemental phosphorus materials (EPMs) constitute the foundation for the synthesis of related compounds. EPMs are experiencing a renaissance in the post-graphene era, thanks to recent advancements in the scaling-down of black phosphorus, amorphous red phosphorus, violet phosphorus, and fibrous phosphorus and consequently, diverse classes of low-dimensional sheets, ribbons, and dots of EPMs with intriguing properties have been produced. The nanostructured EPMs featuring tunable bandgaps, moderate carrier mobility, and excellent optical absorption have shown great potential in energy conversion, energy storage, and environmental remediation. It is thus important to have a good understanding of the differences and interrelationships among diverse EPMs, their intrinsic physical and chemical properties, the synthesis of specific structures, and the selection of suitable nanostructures of EPMs for particular applications. In this comprehensive review, we aim to provide an in-depth analysis and discussion of the fundamental physicochemical properties, synthesis, and applications of EPMs in the areas of energy conversion, energy storage, and environmental remediation. Our evaluations are based on recent literature on well-established phosphorus allotropes and theoretical predictions of new EPMs. The objective of this review is to enhance our comprehension of the characteristics of EPMs, keep abreast of recent advances, and provide guidance for future research of EPMs in the fields of chemistry and materials science. [ABSTRACT FROM AUTHOR]

Single- or few-layer forms of black phosphorus, so called phosphorene, were isolated by exfoliation in 2014 as 2D layered materials holding great promise in electronic and optoelectronic fields. In this perspective, we highlight recent developments in black phosphorus research, in particular, we will focus on the mechanical properties of its 2D form. Its unique puckered structure is responsible for strong anisotropy in mechanical and transport properties, different from graphene and transition-metal dichalcogenide 2D materials. This peculiar mechanical anisotropy can be exploited for applications such as nanomechanical resonators, thermoelectric devices, and motion sensors with tunable functions inaccessible by isotropic materials. Current bottlenecks hindering further progress in devices applications involve first surface degradation in environmental conditions which, in turn, can be exploited in surface friction mechanics to achieve superlubricity. In this framework, the investigation of mechanical properties of phosphorene will be pivotal for facile fabrication, transfer, and resolution of technical hurdles as well the discovery of novel applications. As research directions in next foreseeable future, we will discuss the challenge of crosstalk between mechanical and transport properties, in particular, how the stress–strain stimulations can be used to tune optoelectronic and thermoelectric performance. [ABSTRACT FROM AUTHOR]

2D thin films, possessing atomically thin thickness, are emerging as promising candidates for next-generation electronic devices, due to their novel properties and high performance. In the early years, a wide variety of 2D materials are prepared using several methods (mechanical/liquid exfoliation, chemical vapor deposition, etc.). However, the limited size of 2D flakes hinders their fundamental research and device applications, and hence the effective large-scale preparation of 2D films is still challenging. Recently, pulsed laser deposition (PLD) has appeared to be an impactful method for wafer-scale growth of 2D films, owing to target-maintained stoichiometry, high growth rate, and efficiency. In this review, the recent advances on the PLD preparation of 2D films are summarized, including the growth mechanisms, strategies, and materials classification. First, efficacious strategies of PLD growth are highlighted. Then, the growth, characterization, and device applications of various 2D films are presented, such as graphene, h-BN, MoS 2 , BP, oxide, perovskite, semi-metal, etc. Finally, the potential challenges and further research directions of PLD technique is envisioned., (© 2023 The Authors. Small Methods published by Wiley‐VCH GmbH.)

Low-symmetry 2D materials—such as ReS 2 and ReSe 2 monolayers, black phosphorus monolayers, group-IV monochalcogenide monolayers, borophene, among others—have more complex atomistic structures than the honeycomb lattices of graphene, hexagonal boron nitride, and transition metal dichalcogenides. The reduced symmetries of these emerging materials give rise to inhomogeneous electron, optical, valley, and spin responses, as well as entirely new properties such as ferroelasticity, ferroelectricity, magnetism, spin-wave phenomena, large nonlinear optical properties, photogalvanic effects, and superconductivity. Novel electronic topological properties, nonlinear elastic properties, and structural phase transformations can also take place due to low symmetry. The "Beyond Graphene: Low-Symmetry and Anisotropic 2D Materials" Special Topic was assembled to highlight recent experimental and theoretical research on these emerging materials. [ABSTRACT FROM AUTHOR]

Monolayer group-IV monochalcogenides (MX, M = Ge , Sn, Pb; X = S , Se, Te) are a family of novel two-dimensional (2D) materials that have atomic structures closely related to that of the staggered black phosphorus lattice. The structure of most monolayer MX materials exhibits a broken inversion symmetry and many of them exhibit ferroelectricity with a reversible in-plane electric polarization. A further consequence of the noncentrosymmetric structure is that when coupled with strong spin–orbit coupling, many MX materials are promising for the future applications in non-linear optics, photovoltaics, spintronics, and valleytronics. Nevertheless, because of the relatively large exfoliation energy, the creation of monolayer MX materials is not easy, which hinders the integration of these materials into the fast-developing field of 2D material heterostructures. In this Perspective, we review recent developments in experimental routes to the creation of the monolayer MX, including molecular beam epitaxy and two-step etching methods. Other approaches that could be used to prepare the monolayer MX are also discussed, such as liquid phase exfoliation and solution-phase synthesis. A quantitative comparison between these different methods is also presented. [ABSTRACT FROM AUTHOR]

Tuning ferroelectricity in two-dimensional (2D) ferroelectric materials is important for future applications. Using first-principles calculations, we show that charge doping is an effective way of tuning the ferroelectricity of group IV monochalcogenides MX (M = Ge, Sn; X = S, Se). Our calculations show that hole doping can decrease and even turn off ferroelectricity in SnSe. This can be explained by the change in strengths of in-plane bonds and out-of-plane bonds in this material. In addition, we find that charge doping can effectively change the lattice constants of MX. This indicates that these materials may be good substrates for constructing van der Waals heterojunctions with other 2D materials, in which the moiré pattern can be effectively tuned by doping electrons and holes. [ABSTRACT FROM AUTHOR]

2D materials (2DMs), due to spin‐valley locking degree of freedom, exhibit strongly bound exciton and chiral optical selection rules and become promising material candidates for optoelectronic and spin/valleytronic devices. Over the last decade, the manifesting of 2D materials by circularly polarized lights expedites tremendous fascinating phenomena, such as valley/exciton Hall effect, Moiré exciton, optical Stark effect, circular dichroism, circularly polarized photoluminescence, and spintronic property. In this review, recent advance in the interaction of circularly polarized light with 2D materials covering from graphene, black phosphorous, transition metal dichalcogenides, van der Waals heterostructures as well as small proportion of quasi‐2D perovskites and topological materials, is overviewed. The confronted challenges and theoretical and experimental opportunities are also discussed, attempting to accelerate the prosperity of chiral light‐2DMs interactions. [ABSTRACT FROM AUTHOR]

Phosphorene nanoribbons (PNRs) combine the flexibility of one-dimensional (1D) nanomaterials with the large specific surface area and the edge and electron confinement effects of two-dimensional (2D) nanomaterials. In spite of the substantial advances in bulk black phosphorus (BP) manufacturing, achieving PNRs without degradation is still a big challenge. In this work, we present a strategy for the space-confined chemical vapor transport synthesis of quasi-one-dimensional surface-passivated monocrystalline PNRs on a silicon substrate. The growth mechanism of the PNRs is proposed by combining experimental results and DFT calculations, indicating that the P4 molecules can break, restructure, and epitaxially nucleate on the surface of the Au3SnP7 catalyst, and finally prefer to grow along the zigzag (ZZ) direction to form PNRs. The low gas flow rate and an appropriate phosphorus molecule concentration allow the growth of PNRs with structural integrity, which can be regulated by the amount of red phosphorus and the confined space. [ABSTRACT FROM AUTHOR]

Recent advances in atomically thin two dimensional (2D) anisotropic group IVA‐VI metal monochalcogenides (MMCs) and their fascinating intrinsic properties and potential applications are hampered due to an ongoing challenge of monolayer isolation. Among the most promising MMCs, tin (II) sulfide (SnS) is an earth‐abundant layered material with tunable bandgap and anisotropic physical properties, which render it extraordinary for electronics and optoelectronics. To date, however, the successful isolation of atomically thin SnS single layers at large quantities has been challenging due to the presence of strong interlayer interactions, attributed to the lone‐pair electrons of sulfur. Here, a novel liquid phase exfoliation approach is reported, which enables the overcome of such strong interlayer binding energy. Specifically, it demonstrates that the synergistic action of external thermal energy with the ultrasound energy‐induced hydrodynamic force in solution gives rise to the systematic isolation of highly crystalline SnS monolayers (1L‐SnS). It is shown that the exfoliated 1L‐SnS crystals exhibit high carrier mobility and deep‐UV spectral photodetection, featuring a fast carrier response time of 400 ms. At the same time, monolayer‐based SnS transistor devices fabricated from solution present a high on/off ratio, complemented with a responsivity of 6.7 × 10−3 A W−1 and remarkable stability upon prolonged operation in ambient conditions. This study opens a new avenue for large‐scale isolation of highly crystalline SnS and other MMC manolayers for a wide range of applications, including extended area nanoelectronic devices, printed from solution. [ABSTRACT FROM AUTHOR]

MXenes, an exceptional class of 2D materials, possess high conductivity, adaptable surface chemistry, mechanical strength, and tunable bandgaps, making them attractive for diverse applications. Unlocking the potential of MXenes requires precise control over synthesis methods and surface functionality. Conventionally, fluorine-based etchants are used in MXenes synthesis, posing both environmental concerns and alterations to surface properties, along with the introduction of certain defects. This prompts the exploration of innovative fluorine-free strategies for MXenes synthesis. This review focuses on environmentally friendly, fluorine-free techniques for MXene synthesis, emphasizing mechanisms and recent breakthroughs in alternative etching strategies. The comprehensive coverage includes electrochemical etching, Lewis acid-driven molten salt etching, alkaline/hydrothermal techniques, chemical vapor deposition (CVD), and recent innovative methods. Fluorine-free MXenes synthesis yields terminations such as ─O, ─OH, ─Cl, etc., influencing surface chemistry and improving their properties. The presence of ─OH groups in NaOH etched MXenes boosts their energy storage, while ─Cl functionality from Lewis acidic salts optimizes electrochemical performance. Fluorine-free methods mitigate adverse effects of ─F terminations on MXene conductivity, improving electronic properties and broadening their applications. In addition to traditional approaches, this review delves into novel fluorine-free methods for tailoring MXenes properties. It comprehensively addresses challenges, opportunities, and future perspectives in fluorine-free MXenes., (© 2023 Wiley‐VCH GmbH.)

Futuristic wearable electronics desperately need power sources with similar flexibility and durability. In this regard, the authors, therefore, propose a scalable PAN-PMMA blend-derived electrospinning protocol to fabricate free-standing electrodes comprised of cobalt hexacyanoferrate nanocube cathode and tin metal organic framework-derived nanosphere anode, respectively, for flexible sodium-ion batteries. The resulting unique inter-networked nanofiber mesh offers several advantages such as robust structural stability towards repeated bending and twisting stresses along with appreciable electronic/ionic conductivity retention without any additional post-synthesis processing. The fabricated flexible sodium ion full cells deliver a high working voltage of 3.0 V, an energy density of 273 Wh·kg -1 , and a power density of 2.36 kW·kg -1 . The full cells retain up to 86.73% of the initial capacity after 1000 cycles at a 1.0 C rate. After intensive flexibility tests, the full cells also retain 78.26% and 90.78% of the initial capacity after 1000 bending and twisting cycles (5 mm radius bending and 40 o axial twisting), respectively. This work proves that the proposed approach can also be employed to construct similar robust, free-standing nanofiber mesh-based electrodes for mass-producible, ultra-flexible, and durable sodium ion full cells with commercial viability., (© 2023 Wiley-VCH GmbH.)

Tissue engineering combines materials engineering, cells and biochemical factors to improve, restore or replace various types of biological tissues. A nearly limitless combination of these strategies can be combined, providing a means to augment the function of a number of biological tissues such as skin tissue, neural tissue, bones, and cartilage. Compounds such as small molecule therapeutics, proteins, and even living cells have been incorporated into tissue engineering constructs to influence biological processes at the site of implantation. Peptides have been conjugated to tissue engineering constructs to circumvent limitations associated with conjugation of proteins or incorporation of cells. This review highlights various contemporary examples in which peptide conjugation is used to overcome the disadvantages associated with the inclusion of other bioactive compounds. This review covers several peptides that are commonly used in the literature as well as those that do not appear as frequently to provide a broad scope of the utility of the peptide conjugation technique for designing constructs capable of influencing the repair and regeneration of various bodily tissues. Additionally, a brief description of the construct fabrication techniques encountered in the covered examples and their advantages in various tissue engineering applications is provided. [ABSTRACT FROM AUTHOR]

Summary: Concrete‐filled stainless steel tube (CFSST) members combine the advantages of stainless steel materials and concrete‐filled steel tube (CFST) members. Therefore, it has a broad range of applications than CFST members in the marine environment and other scenarios requiring great durability and corrosion resistance. However, there are limited researches on the large‐sized CFSST members. In this paper, 30 circular CFSST members with varying steel ratios (3.7% ≤ α ≤ 10.3%), diameters (500 mm ≤ D ≤ 900 mm), and strength of concrete (fcu = 40 MPa, 50 MPa) are studied on the size effect under axial compression. For peak axial stress, peak axial strain, and composite elastic modulus, size effects are investigated. According to the results, the peak axial stress and peak axial strain of the members increase with the increase in diameter. The modulus of composite elasticity essentially stays constant as the diameter increases, showing that there is no obvious size effect on the composite elastic modulus. The size effect of peak axial stress and peak axial strain is influenced by the steel ratio. Increasing the steel ratio tended to decrease the size effect. According to the generated data, it was found that the current codes of Chinese and European underestimate the ultimate bearing capacity of CFSST short columns significantly. To this end, the resistances of the large‐sized austenitic CFSST columns with a low steel ratio are well predicted by the proposed design model after being modified, based on GB 50936‐2014 and EN 1994‐1‐1 design codes. [ABSTRACT FROM AUTHOR]

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Signal transducers and activators of transcription 5 (Stat5) is known to engage in regulating the differentiation and effector function of various subsets of T helper cells. However, how Stat5 regulates the antitumor activity of tumor-infiltrating CD4+ T cells is largely unknown. Here, we showed that mice with specific deletion of Stat5 in CD4+ T cells were less susceptible to developing subcutaneous and lung metastatic B16 melanoma with CD4+ tumor-infiltrating lymphocytes (TILs) remolding. Especially, we confirmed that Stat5-deficient CD4+ naïve T cells were prone to polarization of two subtypes of Th17 cells: IFN-γ+ and IFN-γ− Th17 cells, which exhibited increased anti-melanoma activity through enhanced activation of Notch1 pathway compared with wild type Th17 cells. Our study therefore revealed a novel function of Stat5 in regulating tumor-specific Th17 cell differentiation and function in melanoma. This study also provided a new possibility for targeting Stat5 and other Th17-associated pathways to develop novel immunotherapies for melanoma patients. [ABSTRACT FROM AUTHOR]

Extensive experimental and theoretical studies of large rupture strain (LRS) fiber-reinforced polymer (FRP)-confined concrete columns have been conducted based on small-scale columns, mostly with a diameter of 150 mm. This paper presents the first-ever study on the axial performance of LRS polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) FRP-confined large-scale concrete columns. Twenty PET FRP-confined circular concrete columns and 20 PEN FRP-confined square concrete columns were loaded concentrically. The cross-sectional diameter or side length ranged from 100 to 400 mm. The effects of specimen size and FRP volume ratio on the failure mode, axial stress–strain relationship, and dilation behavior were investigated. The load-carrying capacity and ductility of LRS FRP-confined concrete increased with an increase of the FRP volume ratio. As the specimen size increased, the confinement efficiency of the FRP decreased, resulting in a lower strength enhancement. The accuracy of existing size-dependent strength models was also evaluated using the residual error. Furthermore, a modified size-dependent model for LRS FRP-confined circular/square concrete columns was developed, which was shown to have a more satisfactory performance than the existing models. The proposed model can serve as a basic model for the seismic analysis of strengthened reinforced concrete (RC) columns with LRS FRP, with the possible size effect duly accounted. [ABSTRACT FROM AUTHOR]

Herein, linear photogalvanic effect (PGE) phenomena in the BC2P monolayer without and with P‐, B‐, C‐vacancies, and P‐doping, respectively, is investigated, based on density functional theory (DFT) within the nonequilibrium Green's function (NEGF) formalism. It is found that a robust linear PGE at the visible light range is produced in both zigzag and armchair directions for the BC2P photodetector, and photoresponse in the armchair direction is greater by three orders of magnitude than that in the zigzag direction, forming a strong anisotropy on PGE. Moreover, the BC2P armchair photodetector possesses relatively high extinction ratio corresponding to a more sensitive polarization detection. However, except for C‐vacancy case, B‐vacancy, P‐vacancy, P‐doping(B), and P‐doping(C) could not enhance the PGE of armchair photodetector. This work demonstrates further application of the BC2P monolayer for novel electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Combinations of phosphorus with main group III, IV, and V elements are theoretically predicted to generate 2D binary phosphides with extraordinary properties and promising applications. However, experimental synthesis is significantly lacking. Here, a general approach for preparing 2D binary phosphides is reported using single crystalline surfaces containing the constituent element of target 2D materials as the substrate. To validate this, SnP 3 and BiP, representing typical 2D binary phosphides, are successfully synthesized on Cu 2 Sn and bismuthene, respectively. Scanning tunneling microscopy imaging reveals a hexagonal pattern of SnP 3 on Cu 2 Sn, while α-BiP can be epitaxially grown on the α-bismuthene domain on Cu 2 Sb. First-principles calculations reveal that the formation of SnP 3 on Cu 2 Sn is associated with strong interface bonding and significant charge transfer, while α-BiP interacts weakly with α-bismuthene so that its semiconducting property is preserved. The study demonstrates an attractive avenue for the atomic-scale growth of binary 2D materials via substrate phase engineering., (© 2024 Wiley-VCH GmbH.)

Photocatalytic nitrogen fixation using solar illumination under ambient conditions is a promising strategy for production of the indispensable chemical NH 3 . However, due to the catalyst's limitations in solar energy utilization, loss of hot electrons during transfer, and low nitrogen adsorption and activation capacity, the unsatisfactory solar-to-chemical conversion (SCC) efficiencies of most photocatalysts limit their practical applications. Herein, cerium oxide nanosheets with abundant strain-V O defects were anchored on Au hollow nanomushroom through atomically sharp interfaces to construct a novel semiconductor/plasmonic metal hollow nanomushroom-like heterostructure (denoted cerium oxide-AD/Au). Plasmonic Au extended the absorption of light from the visible to the second near-infrared region. The superior interface greatly enhanced the transfer efficiency of hot electrons. Abundant strain-V O defects induced by interfacial compressive strain promoted adsorption and in situ activation of nitrogen, and such synergistic promotion of strain and V O defects was further confirmed by density functional theory calculations. The judicious structural and defect engineering co-promoted the efficient nitrogen photofixation of the cerium oxide-AD/Au heterostructures with a SCC efficiency of 0.1 % under simulated AM 1.5G solar illumination, which is comparable to the average solar-to-biomass conversion efficiency of natural photosynthesis by typical plants, thus exhibiting significant potential as a new candidate for artificial photosynthesis., (© 2023 Wiley-VCH GmbH.)

With the continuous advancement of nanofabrication techniques, development of novel materials, and discovery of useful manipulation mechanisms in high-performance applications, especially photodetectors, the morphology of junction devices and the way junction devices are used are fundamentally revolutionized. Simultaneously, new types of photodetectors that do not rely on any junction, providing a high signal-to-noise ratio and multidimensional modulation, have also emerged. This review outlines a unique category of material systems supporting novel junction devices for high-performance detection, namely, the van der Waals materials, and systematically discusses new trends in the development of various types of devices beyond junctions. This field is far from mature and there are numerous methods to measure and evaluate photodetectors. Therefore, it is also aimed to provide a solution from the perspective of applications in this review. Finally, based on the insight into the unique properties of the material systems and the underlying microscopic mechanisms, emerging trends in junction devices are discussed, a new morphology of photodetectors is proposed, and some potential innovative directions in the subject area are suggested., (© 2023 Wiley-VCH GmbH.)

MXenes are a class of 2D materials that include layered transition metal carbides, nitrides, and carbonitrides. Since their inception in 2011, they have garnered significant attention due to their diverse compositions, unique structures, and extraordinary properties, such as high specific surface areas and excellent electrical conductivity. This versatility has opened up immense potential in various fields, catalyzing a surge in MXene research and leading to note worthy advancements. This review offers an in-depth overview of the evolution of MXenes over the past 5 years, with an emphasis on synthetic strategies, structure-property relationships, and technological prospects. A classification scheme for MXene structures based on entropy is presented and an updated summary of the elemental constituents of the MXene family is provided, as documented in recent literature. Delving into the microscopic structure and synthesis routes, the intricate structure-property relationships are explored at the nano/micro level that dictate the macroscopic applications of MXenes. Through an extensive review of the latest representative works, the utilization of MXenes in energy, environmental, electronic, and biomedical fields is showcased, offering a glimpse into the current technological bottlenecks, such asstability, scalability, and device integration. Moreover, potential pathways for advancing MXenes toward next-generation technologies are highlighted., (© 2023 Wiley-VCH GmbH.)

2D materials with atomic-scale thickness and mechanical robustness are required for flexible devices. The superior optoelectronic properties and high-Z atoms in metal halide perovskites render them desirable for X-ray detection, but the intrinsic brittleness is an obstacle hampering the applications in flexible detectors. Herein, an interfacial engineering strategy is demonstrated for the epitaxial growth of methylammonium lead bromide (MAPbBr 3 ) on black phosphorus (BP) for flexible X-ray detectors. The mechanically robust, high-quality heterostructure consisting of a Pb transition layer is synthesized for the two-way bridging of BP and MAPbBr 3 . Excellent optoelectronic properties such as a high X-ray sensitivity of 1,609 ± 122 µC Gy -1  cm -2 (80 times higher than that of the commercial amorphous Se), a fast response time of 40 ± 5 ms, as well as a low detection limit of 3 µGys -1 (about a fifteenth of the medical chest X-ray dose rate) are achieved from the simple and planar direct X-ray detector fabricated on an organic filter membrane. More importantly, these flat and simple devices are bendable and mechanically durable by exhibiting only 10% photocurrent degradation after 200 bending cycles. The novel heterostructure has great potential in large-area, flexible, and sensitive X-ray detection applications., (© 2023 Wiley-VCH GmbH.)

Layered SnSe is an emerging class of black phosphorus, which is non‐toxic, eco‐friendly, and chemically stable. Recently, SnSe nanostructures have triggered more research interest and enabled broad applications beyond demonstrating their great performances on thermoelectricity. However, there are also a great many significant studies of SnSe nanostructures beyond thermoelectricity. SnSe quantum dots, nanosheets, nanowires, and thin films with diverse morphologies have been synthesized using various chemical and physical preparation approaches. SnSe is a multi‐phase semiconductor, and its nanostructures endow unique properties, including small electron effective mass, ultralow thermal conductivity, huge anisotropy, and the largest 2D piezoelectric coefficient ever predicted. The versatility of SnSe nanostructures can enable potential applications ranging from ultrafast photonics, logic devices, photodetectors, solar cells, photocatalysis, energy storage, and biology to more cutting‐edge interdisciplinary subjects. In this review, the recent advances made in SnSe nanostructures are summarized, covering basics, synthesis, properties, and applications, just giving a passing comment on thermoelectricity. An in‐depth perspective on the challenges and prospects of SnSe nanostructures toward broad and practical applications is also given. [ABSTRACT FROM AUTHOR]

The emerging bandgap-tunable black phosphorous (BP) is a promising material for a compact spectrometer. Here, we report a BP based single-detector monolithic spectrometer operated at broadband mid-infrared. We found that, compared to the spectrally tunable photoresponses of a dual-gate BP transistor, its first deviate to the electric field is more electrostatic-displacement sensitive. This photocurrent deviates as a function of the wavenumber, and electrical gating presents a neat diagonal matrix form, which enables reconstructing the light spectrum with unprecedented spectral and temporal resolutions of ∼2 cm−1 and 2 ms, respectively. We accordingly demonstrated a dynamic on-chip molecular fingerprint analysis. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) tin(II) sulfide (SnS) crystals belong to a class of orthorhombic semiconducting materials with remarkable properties, such as in‐plane anisotropic optical and electronic response, and multiferroic nature. The 2D SnS crystals exhibit anisotropic response along the in‐plane armchair (AC) and zigzag (ZZ) crystallographic directions, offering an additional degree of freedom in manipulating their behavior. Here, advantage of the lack of inversion symmetry of the 2D SnS crystal, that produces second harmonic generation (SHG), is taken to perform polarization‐resolved SHG (P‐SHG) nonlinear imaging of the in‐plane anisotropy. The P‐SHG experimental data are fitted with a nonlinear optics model, allowing to calculate the AC/ZZ orientation from every point of the 2D crystal and to map with high resolution the AC/ZZ direction of several 2D SnS flakes belonging in the same field of view. It is found that the P‐SHG intensity polar patterns are associated with the crystallographic axes of the flakes and with the relative strength of the second‐order nonlinear susceptibility tensor in different directions. Therefore, the method provides quantitative information of the optical in‐plane anisotropy of orthorhombic 2D crystals, offering great promise for performance characterization during device operation in the emerging optoelectronic applications of such crystals. [ABSTRACT FROM AUTHOR]

Thermal‐oxidative stabilization of the polyacrylonitrile (PAN) precursor was performed employing a multi‐step heat treatment strategy in an air circulating furnace. In this approach, the applied temperature was gradually increased from 200°C to 250°C employing several stages for different stabilization durations. Fifteen percent guanidine carbonate (GC) was found as optimum to incorporate with the PAN precursor fibers to accelerate the thermal‐oxidative stabilization process. Characterization techniques, including X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FT‐IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), tensile strength, volume density, linear density, fiber thickness, and burning test have been performed to monitor the changes in PAN structure. Test results of the stabilized samples were compared with the reference sample results to demonstrate the accelerating effect of GC integration. Findings showed that GC pretreatment enhanced and accelerated the cyclization of nitrile groups in the PAN polymer structure and allowed the quicker formation of a thermally stable structure. The analysis of the experimental results revealed that GC integration and employing the multi‐step heat treatment strategy helps greatly to cut the overall PAN‐based carbon fiber production cost. [ABSTRACT FROM AUTHOR]

Low‐dimensional nanomaterials have attracted attention due to their excellent electrical and optical properties. The development of nonvolatile memory device based on low‐dimensional nanomaterials is important for establishing high‐performance computers. In this work, black phosphorus quantum dots (BPQDs) are physically blended with the fullerene derivative [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM), and then polyvinylpyrrolidone (PVP) is added to enhance the film‐forming properties of the material. The resulting composite thin film is sandwiched between aluminum and indium‐tin oxide (ITO) electrodes to form an Al/BPQDs/PCBM/PVP/ITO device. The device exhibits stable nonvolatile rewritable memory behavior, with on and off threshold voltages of −2.4 and +3.25 V, respectively, and an on/off ratio exceeding 103. In addition, the device exhibits a lower threshold voltage and higher conductivity upon increasing the light intensity under laser irradiation at 450 nm. Light‐induced electron paramagnetic resonance and fluorescence spectroscopy show that the existence of electric field‐induced charge transfer and light‐induced charge transfer in the composite thin film are responsible for the device's photoelectric dual‐response resistive characteristics. [ABSTRACT FROM AUTHOR]

Thickness‐dependent chemical and physical properties have gained tremendous interest since the emergence of two‐dimensional (2D) materials. Despite attractive prospects, the thickness‐controlled synthesis of ultrathin nanosheets remains an outstanding challenge. Here, a chemical vapor deposition (CVD) route is reported to controllably synthesize high‐quality PtSe2 nanosheets with tunable thickness and explore their thickness‐dependent electronic and magnetotransport properties. Raman spectroscopic studies demonstrate all Eg, A1g, A2u, and Eu modes are red shift in thicker nanosheets. Electrical measurements demonstrate the 1.7 nm thick nanosheet is a semiconductor with room temperature field‐effect mobility of 66 cm2 V−1 s−1 and on/off ratio of 106. The 2.3–3.8 nm thick nanosheets show slightly gated modulation with high field‐effect mobility up to 324 cm2 V−1 s−1 at room‐temperature. When the thickness is over 3.8 nm, the nanosheets show metallic behavior with conductivity and breakdown current density up to 6.8 × 105 S m–1 and 6.9 × 107 A cm−2, respectively. Interestingly, magnetoresistance (MR) studies reveal magnetic orders exist in this intrinsically non‐magnetic material system, as manifested by the thickness‐dependent Kondo effect, where both metal to insulator transition and negative MR appear upon cooling. Together, these studies suggest that PtSe2 is an intriguing system for both developing novel functional electronics and conducting fundamental 2D magnetism study. [ABSTRACT FROM AUTHOR]