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Manganese dioxide with high theoretical capacity has drawn a great deal of attention for aqueous zinc‐ion batteries (ZIBs). Nevertheless, their sluggish diffusion kinetics, low electrical conductivity and limited active sites are still hindering the potential application in batteries. Herein, amorphous MnO2 nanosheets with abundant oxygen vacancies are facilely prepared by using carboxymethylcellulose sodium (CMC) as a capping agent. During the growth process, CMC can preferentially attach to the (003) facet of MnO2 to guide its crystal growth and morphology. The small nanosheets can expose abundant edge sites, along with the surface oxygen vacancies, to facilitate the insertion/extraction of H+ and Zn2+ in ZIBs. Moreover, the presence of CMC can stabilize the Mn3+ to inhibit the Jahn–Teller effect in the preparation process. As a result, CMC‐MnO2 based ZIB can provide a specific capacity of 324 mAh g−1 at 0.5 A g−1, and achieve 86.2% retention after a long cycle test of 1000 cycles. Furthermore, the energy storage mechanism may be attributed to the insertion/extraction of H+/Zn2+, dissolution/deposition of MnO2 and Zn4SO4(OH)6·nH2O, and irreversible transformation of vermiculite during long cycles. This work may open new perspectives for the development of MnO2‐based cathodes in ZIBs. [ABSTRACT FROM AUTHOR]

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Heterostructured materials show great potential to enhance the specific capacity, rate performance and cycling lifespan of lithium-ion batteries owing to their unique interfaces, robust architectures, and synergistic effects. Herein, a polypyrrole (PPy)-coated nanotube-like Mo3S4/CoMo2S4 heterostructure is prepared by the hydrothermal and subsequent in situ polymerization methods. The well-designed nanotube-like structure is beneficial to relieve the serious volume changes and facilitate the infiltration of electrolytes during the charge/discharge process. The Mo3S4/CoMo2S4 heterostructure could effectively enhance the electrical conductivity and Li+ transport kinetics owing to the refined energy band structure and the internal electric field at the heterostructure interface. Moreover, the conductive PPy-coated layer could inhibit the obvious volume expansion like a firm armor and further avoid the pulverization of the active material and aggregation of generated products. Benefiting from the synergistic effects of the well-designed heterostructure and PPy-coated nanotube-like architecture, the prepared Mo3S4/CoMo2S4 heterostructure delivers high reversible capacity (1251.3 mAh g−1 at 300 mA g−1), superior rate performance (340.3 mAh g−1 at 5.0 A g−1) and excellent cycling lifespan (744.1 mAh g−1 after 600 cycles at a current density of 2.0 A g−1). Such a design concept provides a promising strategy towards heterostructure materials to enhance their lithium storage performances and boost their practical applications. [ABSTRACT FROM AUTHOR]

The use of multi-pore nanostructured g-C 3 N 4 photocatalysts is an efficient approach to separate photogenerated charge carriers and increase visible light photocatalytic performance. Recent progress has yielded nanostructured material through hard templating, which limits potential applications. Integrating the 2D building block into multidimensional porous structures remains a significant challenge in scalable production. Herein, a novel technique based on P407 bubble clusters templating and fixation by freezing is described for the first time to fabricate a 3D opened-up macroporous g-C 3 N 4 nanostructures for photocatalytic H 2 evolution. Three-dimensional hierarchical nanostructures provide more contact active sites and synergistically promote the creation of heterogeneous catalytic interfaces. This feature is very useful for understanding the transfer path of photoinduced charges as well as the origins of the high charge separation efficiency in photocatalytic reactions, thus yielding a remarkable visible light-induced H 2 evolution rate of 4213.6 μmol h−1 g−1, which is nearly 5.6 times (716 μmol h−1 g−1) higher than that of lamellar bulk g-C 3 N 4. This newly developed approach offers a promising alternative to synthesize broad-spectral response 3D hierarchal g-C 3 N 4 nanostructures and can be extended to assemble other functional nanomaterials as building blocks into macroscopic configurations coupled with electronic modulation strategy simultaneously. [Display omitted] • Hierarchically 3DMCNs were synthesized by Poloxamer 407 bubble clusters as a porogen template. • 3DMCN nanostructures with unusual spatial electron transfer properties were systematically demonstrated. • Optical absorption and interfacial reaction active sites were discussed. • The origin of the much superior HER by unique 3DMCN was proposed. [ABSTRACT FROM AUTHOR]

Ultrasound induced cavitation effects can dramatically affect physicochemical performance in photocatalysis as a result of enhanced mass transfer and the formation of highly active radicals under localized high temperature and pressure. The use of ultrasound facilitates a systematic control of photo-generated carrier properties within a nanostructured framework. Considerable research efforts have been directed at developing methodologies for the design of nanostructures with a high degree of precision. We provide a comprehensive overview of rational strategies in the sonochemical synthesis of photocatalysts and address the viability of controlling catalyst structural features. Research progress in sono-photocatalysis and piezo-photocatalysis is assessed, focusing on the integration of cavitation phenomena and artificial nanostructures in terms of practical application. Moreover, we evaluate current technologies used in quantitative analysis as a means of understanding the underlying mechanisms and evaluating catalyst properties predictably and reproducibly. Finally, we provide some insight into the possibilities, limitations and perspectives in this field.

Featured Application: The obtained knowledge can be useful for understanding and optimizing various technologies of nanostructured materials when fast melting processes take place. Interfacial thermal conductance (ITC) affects heat transfer in many physical phenomena and is an important parameter for various technologies. The article considers the influence of various mesoscopic effects on the ITC, such as the heat transfer through the gas gap, near-field radiative heat transfer, and changes in the wetting behavior during melting. Various contributions to the ITC of the liquid-solid interfaces in the processes of fast pre-melting and melting of metal microparticles are studied. The effective distance between materials in contact is a key parameter for determining ITC. This distance changes significantly during phase transformations of materials. An unusual gradual change in ITC recently observed during pre-melting below the melting point of some metals is discussed. The pre-melting process does not occur on the surface but is a volumetric change in the microstructure of the materials. This change in the microstructure during the pre-melting determines the magnitude of the dispersion forces, the effective distance, and the near-field thermal conductance. The knowledge gained can be useful for understanding and optimizing various technological processes, such as laser additive manufacturing. [ABSTRACT FROM AUTHOR]

[Display omitted] Nanocarrier-based drug delivery systems have been designed into various structures that can effectively prevent cancer progression and improve the therapeutic cancer index. However, most of these delivery systems are designed to be simple nanostructures with several limitations, including low stability and burst drug release features. A nano-in-nano delivery technique is explored to address the aforementioned concerns. Accordingly, this study investigated the release behavior of a novel nanoparticles-in-nanofibers delivery system composed of capsaicin-loaded alginate nanoparticles embedded in polycaprolactone-chitosan nanofiber mats. First, alginate nanoparticles were prepared with different concentrations of cationic gemini surfactant and using nanoemulsion templates. The optimized formulation of alginate nanoparticles was utilized for loading capsaicin and exhibited a diameter of 19.42 ± 1.8 nm and encapsulation efficiency of 98.7 % ± 0.6 %. Likewise, blend polycaprolactone-chitosan nanofibers were prepared with different blend ratios of their solutions (i.e., 100:0, 80:20, 60:40) by electrospinning method. After the characterization of electrospun mats, the optimal nanofibers were employed for embedding capsaicin-loaded alginate nanoparticles. Our findings revealed that embedding capsaicin-loaded alginate nanoparticles in polycaprolactone-chitosan nanofibers, prolonged capsaicin release from 120 h to more than 500 h. Furthermore, the results of in vitro analysis demonstrated that the designed nanoplatform could effectively inhibit the proliferation of MCF-7 human breast cells while being nontoxic to human dermal fibroblasts (HDF). Collectively, the prepared nanocomposite drug delivery platform might be promising for the long-term and controlled release of capsaicin for the prevention and treatment of cancer. [ABSTRACT FROM AUTHOR]

Heterostructured materials show great potential to enhance the specific capacity, rate performance and cycling lifespan of lithium-ion batteries owing to their unique interfaces, robust architectures, and synergistic effects. Herein, a polypyrrole (PPy)-coated nanotube-like Mo3S4/CoMo2S4 heterostructure is prepared by the hydrothermal and subsequent in situ polymerization methods. The well-designed nanotube-like structure is beneficial to relieve the serious volume changes and facilitate the infiltration of electrolytes during the charge/discharge process. The Mo3S4/CoMo2S4 heterostructure could effectively enhance the electrical conductivity and Li+ transport kinetics owing to the refined energy band structure and the internal electric field at the heterostructure interface. Moreover, the conductive PPy-coated layer could inhibit the obvious volume expansion like a firm armor and further avoid the pulverization of the active material and aggregation of generated products. Benefiting from the synergistic effects of the well-designed heterostructure and PPy-coated nanotube-like architecture, the prepared Mo3S4/CoMo2S4 heterostructure delivers high reversible capacity (1251.3 mAh g−1 at 300 mA g−1), superior rate performance (340.3 mAh g−1 at 5.0 A g−1) and excellent cycling lifespan (744.1 mAh g−1 after 600 cycles at a current density of 2.0 A g−1). Such a design concept provides a promising strategy towards heterostructure materials to enhance their lithium storage performances and boost their practical applications.

Covalent-organic-framework (COF) materials with a designable periodic framework have been expected as a kind of promising anode material for potassium ion batteries (PIBs). However, these materials suffer seriously from low capacity, poor rate performance, and slow reaction kinetics during the K-storage process, significantly limiting their widespread applications. Herein, a three-dimensional (3D) COF material denoted as CN-COF with a high N content and defined configuration as well as a graphite-like layer stacking structure was developed as a promising anode to realize efficient 3D K-storage performance with enhanced interfacial stability and reaction kinetics via an electrolyte chemistry compatibility strategy. Particularly, a uniform and stable solid-electrolyte interphase (SEI) with rich inorganic components was controllably formed in the optimized high-concentration THF-based electrolyte (HTE), ensuring satisfactory cycling stability as well as rapid diffusion kinetics. As a result, the synthesized CN-COF material in this optimized electrolyte delivered a high reversible capacity of 385.8 mAh/g at 50 mA/g, and a well-maintained 95.3 mAh/g after 1500 cycles at 500 mA/g. This work provides innovative design and manipulation of the K-storage mechanism via the synergistic effect between nanostructure design and electrolyte chemistry for advanced K-storage materials.

PbSe, a promising Te-free thermoelectric material for medium-temperature applications, has garnered considerable attention due to its substantial thermoelectric potential and relatively low cost. However, the vast majority of research on polycrystalline PbSe thermoelectrics has focused primarily on improving its medium-temperature performance, often neglecting the enhancement of near-room-temperature performance and effective module design. Here, an n-type polycrystalline PbSe material (Cu 0.01 Pb 0.85 Ge 0.15 Se) is presented that exhibits a room-temperature zT of ≈0.6 and an average zT of 0.86 from 303 to 523 K. This superior performance is realized through the incorporation of a high-concentration Ge into n-type Cu 0.01 PbSe, which induces a novel pseudo-nanostructure and grain refinement, promoting electron-phonon decoupling. Based on this, seven-pair module devices are fabricated, achieving a record-high conversion efficiency of up to 5.1% at a temperature difference of only 228 K, and an unprecedented maximum cooling temperature difference of 47.2 K when the hot-side temperature is 350 K. The findings provide a strong foundation for advancing Te-free polycrystalline PbSe-based materials for thermoelectric cooling and low-temperature power generation., (© 2024 Wiley‐VCH GmbH.)

Owing to the abundant resources of potassium resources, potassium ion batteries (PIBs) hold great potential in various energy storage devices. However, the poor lifespan of PIBs anodes limit their merchant applications. The exploitation of anode materials with high performance is one of the critical factors to the development of PIBs. Metallic Sn‐, Sb‐, and Bi‐based materials, show promising future thanks to their high theoretical capacities and safe working voltage. However, the rapid capacity decay caused by the large K+ is still a pivotal challenge. In this review, recent progresses on alloying anodes were summarized. Schemes, such as ultra‐small nanoparticles, hetero‐element doping, and electrolyte optimization are effective strategies to improve their electrochemical properties. This review provides an outlook on the nanostructures and their synthesis methods for the alloying‐type materials, and will stimulate their intensive study for practical application in the near future. [ABSTRACT FROM AUTHOR]

Interfacial thermal conductance (ITC) affects heat transfer in many physical phenomena and is an important parameter for various technologies. The article considers the influence of various mesoscopic effects on the ITC, such as the heat transfer through the gas gap, near-field radiative heat transfer, and changes in the wetting behavior during melting. Various contributions to the ITC of the liquid-solid interfaces in the processes of fast pre-melting and melting of metal microparticles are studied. The effective distance between materials in contact is a key parameter for determining ITC. This distance changes significantly during phase transformations of materials. An unusual gradual change in ITC recently observed during pre-melting below the melting point of some metals is discussed. The pre-melting process does not occur on the surface but is a volumetric change in the microstructure of the materials. This change in the microstructure during the pre-melting determines the magnitude of the dispersion forces, the effective distance, and the near-field thermal conductance. The knowledge gained can be useful for understanding and optimizing various technological processes, such as laser additive manufacturing.

The smart temperature-adaptive superhydrophobic radiative cooling CFs were created through a nanoengineering design strategy by a simple and scalable layer-by-layer spraying method. These wearable materials can switch dynamically between white and colorful in response to temperature variations, modifying solar spectrum reflectance and absorptance to manage cooling and heating, achieving energy-efficient and intelligent temperature control for winter warming and summer cooling. [Display omitted] • Smart radiative cooling superhydrophobic CFs-based materials were fabricated. • The wearable materials contain a thermochromic layer and a radiative cooling layer. • The wearable materials inherit the favorable characteristics of collagen fibers. • The STSRC-CFs can switch dynamically between white and other colors. • This work attains smart temperature regulation for winter warming and summer cooling. As traditional biomaterials for wearables, collagen fibers (CFs)-based products are widely used in daily life due to their exceptional performance. However, developing CFs-derived products that exhibit seasonal self-adaptive temperature regulation to satisfy the thermal comfort for humans and prolong their service life remains a significant challenge in practical applications. Herein, the smart temperature-adaptive superhydrophobic radiative cooling CFs (STSRC-CFs) were created through a nanoengineering design strategy by a simple and scalable layer-by-layer spraying method. The STSRC-CFs inherit the outstanding properties of natural CFs and maintain high tensile strength (18.2 MPa), air permeability (38.2 mL/cm2∙h), and superhydrophobicity (CA of 161.1°, SA of 2.0°). Moreover, STSRC-CFs possessed a thermal emittance of 0.94, while the solar reflectance could be dynamically modulated in response to the ambient temperature change with a solar reflectance of 0.91 at high temperatures and 0.81 at low temperatures. The synergic effect enables STSRC-CFs to autonomously manage radiative cooling and solar heating, thereby achieving intelligent energy-saving temperature regulation for winter warming and summer cooling. Notably, the superhydrophobic self-cleaning effect of STSRC-CFs prevents from contamination, ensuring sustained spectral modulation and intelligent temperature regulation. Serving as a proof-of-concept for intelligent self-adaptive passive temperature regulation, the STSRC-CFs introduced in this study lay the groundwork for the development of advanced temperature-adaptive radiative cooling and solar heating functional materials. [ABSTRACT FROM AUTHOR]

Microwave absorbing material is a kind of material that can absorb microwave and electromagnetic (EM) energy and has less reflection and scattering. Qualified microwave absorbers can effectively prevent EM pollution and protect human health. This review briefly introduces the principles of microwave absorption (MA), more importantly, the research progress in the nanostructure design and composition regulation of carbon spheres (CSs) are reviewed. The nanostructure design is dominated by hollow and porous nature, and the composition regulation is based on conductive/dielectric, magnetic, as well as conductive/dielectric-magnetic components. Due to the synergistic effect among varieties of components and the clever nanostructure design, the CSs and their composites can achieve preferable MA performance than traditional carbon materials. At the same time, the challenges and prospects of the research on CSs are put forward, which provide new ideas for further study of microwave absorption based on CSs. This review mainly reports the structure design and composition regulation of carbon based absorbers with tunable absorbent performance. Structure design is given priority to with hollow and hollow porous structures, and the composition regulation is adjusted mainly by adding conductive, dielectric and magnetic materials. [Display omitted] [ABSTRACT FROM AUTHOR]

The fast-developing field of RNA nanotechnology requires the adoption and development of novel and faster computational approaches to modeling and characterization of RNA-based nano-objects. We report the first application of Elastic Network Modeling (ENM), a structure-based dynamics model, to RNA nanotechnology. With the use of an Anisotropic Network Model (ANM), a type of ENM, we characterize the dynamic behavior of non-compact, multi-stranded RNA-based nanocubes that can be used as nano-scale scaffolds carrying different functionalities. Modeling the nanocubes with our tool NanoTiler and exploring the dynamic characteristics of the models with ANM suggested relatively minor but important structural modifications that enhanced the assembly properties and thermodynamic stabilities. In silico and in vitro, we compared nanocubes having different numbers of base pairs per side, showing with both methods that the 10 bp-long helix design leads to more efficient assembly, as predicted computationally. We also explored the impact of different numbers of single-stranded nucleotide stretches at each of the cube corners and showed that cube flexibility simulations help explain the differences in the experimental assembly yields, as well as the measured nanomolecule sizes and melting temperatures. This original work paves the way for detailed computational analysis of the dynamic behavior of artificially designed multi-stranded RNA nanoparticles.

The successful development of post‐lithium technologies depends on two key elements: performance and economy. Because sodium‐ion batteries (SIBs) can potentially satisfy both requirements, they are widely considered the most promising replacement for lithium‐ion batteries (LIBs) due to the similarity between the electrochemical processes and the abundance of sodium‐based resources. Among various SIB anode materials, metal sulfides are most extensively studied as materials for high‐performance electrodes due to the versatility of their synthesis procedure, utilization potential, and high sodiation capacity. Herein, some of the most effective strategies aimed at effectively alleviating the performance shortcomings of these materials from the materials engineering/design perspective are summarized. In terms of facilitating ion transport in SIBs, which represents one of the most critical aspects of their performance, a specific family of strategies related to a particular operational mechanism is considered rather than categorizing based‐on individual sulfide materials. In the foreseeable future, the development of highly functional SIBs electrode materials and utilization of metal sulfides will become highly relevant due to their stability and performance characteristics. Therefore, it is anticipated that this review will guide further research and facilitate the realization of various applications of sulfide‐based high‐performance rechargeable batteries. [ABSTRACT FROM AUTHOR]

This review focuses on the advanced design and optimization of nanostructured zinc-air batteries (ZABs), with the aim of boosting their energy storage and conversion capabilities. The findings show that ZABs favor porous nanostructures owing to their large surface area, and this enhances the battery capacity, catalytic activity, and life cycle. In addition, the nanomaterials improve the electrical conductivity, ion transport, and overall battery stability, which crucially reduces dendrite growth on the zinc anodes and improves cycle life and energy efficiency. To obtain a superior performance, the importance of controlling the operational conditions and using custom nanostructural designs, optimal electrode materials, and carefully adjusted electrolytes is highlighted. In conclusion, porous nanostructures and nanoscale materials significantly boost the energy density, longevity, and efficiency of Zn-air batteries. It is suggested that future research should focus on the fundamental design principles of these materials to further enhance the battery performance and drive sustainable energy solutions., (© 2024 Wiley‐VCH GmbH.)

We present a new method based on Weierstrass factorization to optimize broadband perfect absorber (BPA) made of metal-dielectric-metal elements, which is an efficient and general approximation to calculate the absorption of these subwavelength structures. With the resonant wavelengths estimated by semi-analytical equations, we design a planar BPA tiling three subunits in one unit cell and a vertical tapered BPA stacking 20 pairs of metal-dielectric layers in one unit cell. Both BPAs shows almost over 90% and wide angle absorption in the concerned range. This method can be an alternative to the traditional full vector methods in initial design.

Nanostructure design and in situ transmission electron microscopy (TEM) are combined to demonstrate Sb‐based nanofibers composed of bunched yolk–shell building units as a significantly improved anode for potassium‐ion batteries (PIBs). Particularly, a metal–organic frameworks (MOFs)‐engaged electrospinning strategy coupled to a confined ion‐exchange followed by a subsequent thermal reduction is proposed to fabricate yolk–shell Sb@C nanoboxes embedded in carbon nanofibers (Sb@CNFs). In situ TEM analysis reveals that the inner Sb nanoparticles undergo a significant volume expansion/contraction during the alloying/dealloying processes, while the void space can effectively relieve the overall volume change, and the plastic carbon shell maintains the structural integrity of electrode material. This work provides an important reference for the application of advanced characterization techniques to guide the optimization of electrode material design. [ABSTRACT FROM AUTHOR]

• Three different morphologies of MnCo 2 O 4.5 spinel oxides prepared via structural regulation. • Various MnCo 2 O 4.5 structures optimize dielectric properties and impedance matching and introduce polarization processes. • The microcubic spheres structure of MnCo 2 O 4.5 achieved satisfactory EMW absorption performance in the X-band. • The MCO-MSs exhibit RL min of −51.52 dB at a thickness of 2.3 mm and EAB max of 5.36 GHz at a thickness of 2.2 mm. The cobalt-based spinel structure oxides with synergistic effect of magnetic loss and dielectric loss have important applications in electromagnetic wave absorption. And the excess 0.5 oxygen atoms in MnCo 2 O 4.5 provide more vacancies than traditional MnCo 2 O 4 spinel structure and improve the electrical conductivity. In the current study, MnCo 2 O 4.5 microsphere clusters, MnCo 2 O 4.5 microcubic spheres and MnCo 2 O 4.5 flowery spheres were prepared by solvothermal method and annealing process. Among the final samples with different morphologies, MnCo 2 O 4.5 microcubic spheres showed outstanding microwave absorption capabilities, with a minimum reflection loss (RL min) of -51.52 dB at 2.2 mm. When the thickness was further increased to 2.3 mm, the effective absorption bandwidth could be as wide as 5.36 GHz, covering most of the X-band. The excellent absorption performance of electromagnetic waves is related to the modulability of the complex dielectric parameters, the optimization of impedance matching, and the enhancement of the polarization relaxation process through the improvement of the morphologies. This work provides guidance and support for refining the electromagnetic wave absorption potential of cobalt-based spinel oxides and for designing highly efficient electromagnetic wave absorbers in the X-band. MnCo 2 O 4.5 with multiple morphologies was prepared to modulate the complex dielectric parameters of the materials and to optimize the impedance matching, further enhancing the polarization relaxation process. [Display omitted] [ABSTRACT FROM AUTHOR]

We present a new method based on Weierstrass factorization to optimize broadband perfect absorber (BPA) made of metal-dielectric-metal elements, which is an efficient and general approximation to calculate the absorption of these subwavelength structures. With the resonant wavelengths estimated by semi-analytical equations, we design a planar BPA tiling three subunits in one unit cell and a vertical tapered BPA stacking 20 pairs of metal-dielectric layers in one unit cell. Both BPAs shows almost over 90% and wide angle absorption in the concerned range. This method can be an alternative to the traditional full vector methods in initial design. [ABSTRACT FROM AUTHOR]

Rational design on microstructure of magnetic material provides new opportunity to enhance the electromagnetic absorption performance. Herein, we demonstrate the successful preparation of spindle-cone of Fe/Fe 2 O 3 and Fe 3 O 4 samples with an average size of ∼1.2 μm, using a facile two-steps method. The well-defined spindle-cone shaped α-Fe 2 O 3 was developed first by a solvothermal route and then reduced by H 2 or NaBH 4 , respectively. The morphologies, phase compositions and magnetization of these as-prepared samples are analyzed by Field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and X-ray photoelectron spectrum (XPS) and vibrating sample magnetometer (VSM). Meanwhile, the electromagnetic (EM) absorption performance of Fe/Fe 2 O 3 and Fe 3 O 4 spindle-cones-paraffin composites with various filling ratios are also studied. The results reveal that Fe/Fe 2 O 3 with a filling ratio of 50 wt% achieves the smallest reflection loss value of −26.2 dB at a thickness of 1.4 mm. At thinner thickness (1.0 mm), the bandwidth (RL < −10 dB) equals to 4.5 GHz (13.5–18 GHz). The excellent absorption mechanism was discussed in this work, which attributed to the unique nanostructure and moderate impedance matching and EM loss ability. • Spindle-cone shaped magnetic hybrid was prepared by a simple two-steps method. • Fe 3 O 4 and Fe/Fe 2 O 3 could be achieved using different reduction regent. • The effective absorption frequency of Fe/Fe 2 O 3 absorber was up to 4.5 GHz with a thickness of 1.4 mm. • Such a spindle-cone shape attributed to the performance. [ABSTRACT FROM AUTHOR]

Heterostructured materials show great potential to enhance the specific capacity, rate performance and cycling lifespan of lithium-ion batteries owing to their unique interfaces, robust architectures, and synergistic effects. Herein, a polypyrrole (PPy)-coated nanotube-like Mo 3 S 4 /CoMo 2 S 4 heterostructure is prepared by the hydrothermal and subsequent in situ polymerization methods. The well-designed nanotube-like structure is beneficial to relieve the serious volume changes and facilitate the infiltration of electrolytes during the charge/discharge process. The Mo 3 S 4 /CoMo 2 S 4 heterostructure could effectively enhance the electrical conductivity and Li + transport kinetics owing to the refined energy band structure and the internal electric field at the heterostructure interface. Moreover, the conductive PPy-coated layer could inhibit the obvious volume expansion like a firm armor and further avoid the pulverization of the active material and aggregation of generated products. Benefiting from the synergistic effects of the well-designed heterostructure and PPy-coated nanotube-like architecture, the prepared Mo 3 S 4 /CoMo 2 S 4 heterostructure delivers high reversible capacity (1251.3 mAh g -1 at 300 mA g -1 ), superior rate performance (340.3 mAh g -1 at 5.0 A g -1 ) and excellent cycling lifespan (744.1 mAh g -1 after 600 cycles at a current density of 2.0 A g -1 ). Such a design concept provides a promising strategy towards heterostructure materials to enhance their lithium storage performances and boost their practical applications.

Abstract: Sodium‐ion technology has the potential to become the next generation of low cost and environmentally friendly electrochemical energy storage system for grid‐level applications. The low cost and abundant raw materials employed in sodium cells have driven the recent increasing interest in sodium‐ion batteries (SIBs), which appear especially appealing, since manufacturers can use the already existing production technology of lithium‐ion batteries. However, SIBs are still an early stage technology, which requires several issues affecting cell performance to be addressed. Despite the accelerated development of cathode materials, anode materials still require further investigation and optimization to reach high energy density performance. In the pursuit of high capacity anode materials, several alloying‐, conversion‐, and combined conversion–alloying‐based electrodes have been investigated. This review offers a comprehensive overview on the recent progresses toward the realization of “beyond‐insertion” anode materials. The role of nanostructuration with the associated advantages and disadvantages is presented for each class of compounds, combined with the main strategies adopted to improve the electrochemical behavior. Finally, an overview of the challenges and perspectives associated with the development of the next generation of anode materials is presented with a particular focus on the role of the electrolyte solutions and solid/electrolyte interphase. [ABSTRACT FROM AUTHOR]

ABSTRACT: The modification of epoxy composites through the construction of nanostructures via the self‐organization of block copolymers in epoxy has become a hot topic. In this research, polystyrene‐b‐poly(ɛ‐caprolactone)‐b‐polydimethylsiloxane‐b‐poly(ɛ‐caprolactone)‐b‐polystyrene (PS‐PCL‐PDMS‐PCL‐PS) block copolymers with different lengths of PS subchains were synthesized and incorporated into epoxy thermoset. Due to the difference in the length of PS subchains, two different sizes of core‐shell nanostructures were obtained. When these two block copolymers were incorporated into epoxy, the tensile strength, elongation at break, damping temperature in range (tan δ > 0.2), and storage modulus of the epoxy thermoset below 105 °C were simultaneously improved. Meanwhile, the effects of the lengths of PS subchains on the size of nanostructures and the relationship between microstructure and macroscopic properties of epoxy composites were systematically investigated. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46362. [ABSTRACT FROM AUTHOR]

[Display omitted] • The relationships among cavitation mechanism, nanostructured design and performance improvement are considered. • Versatile preparing routes for photocatalysts with high activities are presented. • Engineering strategies for ultrasound-assisted and piezo-enhanced photocatalysis are reviewed. • Characterization for mechanism interpretation and parameters optimization are demonstrated. Ultrasound induced cavitation effects can dramatically affect physicochemical performance in photocatalysis as a result of enhanced mass transfer and the formation of highly active radicals under localized high temperature and pressure. The use of ultrasound facilitates a systematic control of photo-generated carrier properties within a nanostructured framework. Considerable research efforts have been directed at developing methodologies for the design of nanostructures with a high degree of precision. We provide a comprehensive overview of rational strategies in the sonochemical synthesis of photocatalysts and address the viability of controlling catalyst structural features. Research progress in sono-photocatalysis and piezo-photocatalysis is assessed, focusing on the integration of cavitation phenomena and artificial nanostructures in terms of practical application. Moreover, we evaluate current technologies used in quantitative analysis as a means of understanding the underlying mechanisms and evaluating catalyst properties predictably and reproducibly. Finally, we provide some insight into the possibilities, limitations and perspectives in this field. [ABSTRACT FROM AUTHOR]

This study investigated the impact of the nanostructure design of titanium nitride (TiN x) thin films on their optical, electrical and thermal properties. The growth designs of the films were tailored using conventional sputtering (series 1) and GLancing Angle Deposition (GLAD) geometries (series 2 and 3). The results showed the potential to modify the properties of thin films by adjusting their nanostructure design, rather than changing their composition. TiN x thin films prepared by GLAD, revealed wider and more significant variations in optical and electrical properties, while the thermal properties seemed to be more affected by the structural changes promoted by the N content in the films. GLAD geometries resulted in the reduction of the film's reflectivity, and colour coordinates, as well as an increase in the electrical resistivity. The thermal parameters of effusivity ratio and diffusivity were reduced as the N/Ti ratio increased. • Tailoring of thin films nanostructure design by GLancing Angle Deposition (GLAD). • Correlation between processing parameters and TiN thin films' characteristics. • Influence of roughness, pore density and grain size on the optical, electrical and thermal properties of TiN thin films. • Change thin films' responses by acting on their growing design and their morphological and structural features. • The possibility to extend thin films' responses beyond the conventional composition variation influence. [ABSTRACT FROM AUTHOR]

Despite its widespread use in signal collection, flexible sensors have been rarely used in human-machine interactions owing to its indistinguishable signal, poor reliability, and poor stability when inflicted with unavoidable scratches and/or mechanical cuts. A highly sensitive and self-healing sensor enabled by multiple hydrogen bonding network and nanostructured conductive network is demonstrated. The nanostructured supramolecular sensor displays extremely fast (ca. 15 s) and repeatable self-healing ability with high healing efficiency (93 % after the third healing process). It can precisely detect tiny human motions, demonstrating highly distinguishable and reliable signals even after cutting-healing and bending over 20 000 cycles. Furthermore, a human-machine interaction system is integrated to develop a facial expression control system and an electronic larynx, aiming to control the robot to assist the patient's daily life and help the mute to realize real-time speaking. [ABSTRACT FROM AUTHOR]

Introduction. The aim of the study was to assess the formation of biomimetic calcium hydroxyapatite (HAP) on the surface of different substrates. Material and Methods. Silica coated stainless steel tapes and thin polymer films (alginate, cellulose, poly lactide-co-glycolide - PLGA) deposited on hydroxyapatite scaffold were used as substrate. Supersaturated simulated body fluid (SBF) and SBF combined with Fetal Calf Serum (FCS) or Eagle’s Minimum Essential Medium (EMEM) were used as bioactive liquid medium where biomimetic nucleation of HAP occurred. Infrared spectroscopy with Fourier transformation was used to analyze the formed phases, while scanning electron microscopy indicated the morphology of nucleated phase. Results. The results of measuring the mass with volume adjustments done by the BET method showed that the thickness of the film of nucleated calcium hydroxyapatite depended on the time that samples spent soaked in SBF-in as well as the type of selected biomimetic medium. Conclusion. Biomimetic calcium hydroxyapatite is possible to produce by self nucleation on different substrates in the presence of simulating body fluid.

We report an enhancement in light emission of a GaN-based blue light-emitting diode (LED) with periodic indium tin oxide (ITO) nanodisc arrays. The periodic nanodisc arrays were elaborately designed by the Bragg diffraction and the maximum transmittance of a model of bilayer film on a GaN epitaxial layer. In the experiment, the periodic ITO nanodisc arrays have been fabricated by polystyrene nanosphere lithography. The electroluminescence intensity of the LEDs with periodic ITO nanodisc arrays is better than that of conventional planar GaN-based LED, and the greatest enhancement could increase the intensity by a factor of 2.08 at an operating current of 20 mA compared with the conventional planar GaN-based LED. The simulation results based on three-dimensional finite difference time-domain method showed that the LED with periodic ITO nanodisc arrays can improve the light-extraction efficiency of LED by enhancing the critical angle of light output. This method would be valuable for the fabrication of high-efficiency planar GaN-based LEDs. [ABSTRACT FROM PUBLISHER]

The development of competitive Na- and Mg-ion batteries (NIBs and MIBs) with performance comparable to Li-ion batteries is hindered by the major challenge of finding advanced electrode materials. In this work, nanostructured TiS 2 electrodes including nanosheets, nanoribbons and nanotubes are shown by first principles calculations to achieve improved Na and Mg ion diffusion as compared with the bulk phase. Comparative studies between Li, Na, and Mg reveal that the diffusion kinetics of Na ions would especially benefit from the nanostructure design of TiS 2 . More specifically, the Na ion diffusivity turns out to be considerably higher than Li ion diffusivity, which is opposite to that observed in bulk TiS 2 . However, in the case of Mg ions, fast diffusion is still beyond attainment since a relatively high degree of interaction is expected between Mg and the S atoms. Edge-induced modifications of diffusion properties appear in both Na and Mg ions, while the mobility of Li ions along the ribbon edges may not be as appealing. Effects of the curvature of nanotubes on the adsorption strength and ion conductivity are also explored. Our results highlight the nanostructure design as a rich playground for exploring electrodes in NIBs and MIBs. [ABSTRACT FROM AUTHOR]

The balance between degradability and drug release kinetics is a major challenge for the development of drug delivery systems. Here we develop hierarchically structured nanoparticles comprising multiple noncontact silica shells using an amorphous calcium carbonate template. The system could be degraded in a sequential fashion on account of the molecularly engineered multishelled structures. The hydrolysis rate of drug-containing cores is inversely correlated with the nanoparticle concentration due to the shielding effect of the hierarchical nanostructure and could be exploited to regulate the release kinetics. Specifically, multishelled nanospheres show a low drug release rate with high doses that increases steadily as the concentration decreases due to continuous degradation, thus stabilizing the local drug concentration for effective tumor therapy. Moreover, the nanoparticles could be eventually degraded completely, which may reduce their health risks. This kind of hierarchically structured silica-based nanoparticle could serve as a sustainable drug depot and provides a new avenue for tumor treatment.

Owing to their rich surface chemistry, high conductivity, tunable bandgap, and thermal stability, structured 2D transition-metal carbides, nitrides, and carbonitrides (MXenes) with modulated atomic environments have emerged as efficient electrochemical energy conversion systems in the past decade. Herein, the most recent advances in the engineering of tunable structured MXenes as a powerful new platform for electrocatalytic energy conversion are comprehensively summarized. First, the state-of-the-art synthetic and processing methods, tunable nanostructures, electronic properties, and modulation principles of engineering MXene-derived nanoarchitectures are focused on. The current breakthroughs in the design of catalytic centers, atomic environments, and the corresponding structure-performance correlations, including termination engineering, heteroatom doping, defect engineering, heterojunctions, and alloying, are discussed. Furthermore, representative electrocatalytic applications of structured MXenes in energy conversion systems are also summarized. Finally, the challenges in and prospects for constructing MXene-based electrocatalytic materials are also discussed. This review provides a leading-edge understanding of the engineering of various MXene-based electrocatalysts and offers theoretical and experimental guidance for prospective studies, thereby promoting the practical applications of tunable structured MXenes in electrocatalytic energy conversion systems., (© 2022 Wiley-VCH GmbH.)

A rational design and selection of electrocatalytic cathode host materials are significant to achieve sustainable, efficient and stable catalysis towards H 2 O 2 electroreduction. Herein, we described a facile synergetic strategy to generate a novel free-standing electrode (Pd-Co 3 O 4 /3D RGO@polyimide (PI) foam, PCRP) with well-developed porous and hollow structure, which derived from cobalt-based MOFs (ZIF-67) as an advanced Pd host, rooting on the 3D conductive graphene/PI foam to realize the significant promotion towards H 2 O 2 electroreduction. Such 3D hollow structure design not only offers a high specific area to develop a number of exposed catalytic activity sites but also restricts the aggregation of nanoparticle catalysts within catalysis. Utilizing the electrode structural advantages and reducing the particle diameter of noble metal catalysts to improve the catalytic performance was possible. When evaluated as a co-catalyst for H 2 O 2 electroreduction, the as-developed electrode displayed an optimized reduction current density of 962 mA·cm−2 at −0.8 V in alkaline due to the synergetic influence of Pd nanoparticles and Co 3 O 4 hollow cages. Notably, the loading of noble metal on the PCRP electrode was only close to 2.0 wt% in Pd-Co 3 O 4 hybrids. What's more, the obtained PCRP electrode also exhibited robust stability, low apparent activation energy (9.071 kJ·mol−1), good reproducibility and repeatability (903 mA·cm−2after 1000 cycles with a 0.0058% current density decay per cycle at −0.8 V) superior to that of single Co 3 O 4 nanoparticles or Co 3 O 4 /3D RGO hybrids with simple configuration, implying its great promise for novel energy transformation systems. [Display omitted] • A Pd-Co 3 O 4 /3D RGO@polyimide (PCRP) electrode was successfully developed. • Hollow structure Co 3 O 4 derived from MOFs as Pd host supported on graphene substrate. • The electrode presented characteristics of small particle diameter and low loading of Pd. • The synergism of structure and constituent promoted electrocatalytic performance. • The electrode exhibited excellent stability, reproducibility, low apparent activation energy. [ABSTRACT FROM AUTHOR]

Potassium-ion batteries (PIBs) have attracted widespread attention in recent years due to their potential advantages such as low cost and high energy density. However, the large radius of K + and the low potassium storage capacity of some electrode materials limit their development. Antimony (Sb)-based materials are considered to be promising anode materials for PIBs in view of their high K storage capacity and low potassiation potential. Nonetheless, the huge volume variation caused by potassiation/depotassiation often leads to their failure. Previous works have proved that carbon coating and nanostructure design are important means to alleviate the volume effect. Herein, the carbon-coating technology and nanostructure design were combined to prepare a Sb-based nanomaterial with Sb/Sb 2 S 3 hybrid nanorod fragments confined in a carbon hollow tube (Sb/Sb 2 S 3 @CHT). Such a nanostructure is beneficial to alleviate the volume change of the Sb/Sb 2 S 3 hybrids while facilitating the kinetics of the electrochemical reaction. As a consequence, the Sb/Sb 2 S 3 @CHT anode electrode exhibits high rate performance and outstanding cycle stability characterized by retaining a high specific capacity of 400.9 mA h g -1 after cycling for 200 cycles at 200 mA g -1 .

• A new formation strategy of yolk-shell structured nanospheres was proposed. • Yolk-shell nanospheres with tunable compositions of yolk and shell parts were synthesized. • Unique structured iron oxide-C nanospheres showed excellent lithium-ion storage performances. Yolk-shell structure architecture is considered to be important in the fields that requires nanostructured designs such as energy storage systems. In particular, the internal and external structures, as well as compositions of yolk-shell materials, should be controllable in wide ranges to improve their properties for efficient applications in various fields. In this study, a new and general strategy to fabricate yolk-shell nanospheres with tunable compositions of yolk and shell parts under mild vacuum conditions is proposed. The melted metal salt is infiltrated in the void space of the hollow porous carbon nanospheres to form a yolk-shell structure under vacuum conditions, resulting in a yolk-shell structure with the configuration of a transition metal oxide (TMO)@void@C after a decomposition process under a vacuum. Yolk-shell nanospheres with configurations of TMO@void@TMO-C and TMO-C@void@TMO-C are also synthesized by controlling the vacuum degree for the infiltration of metal salt. Iron oxide, nickel oxide, and multicomponent materials are applied to confirm the applicability of the suggested method. This method facilitated in the tuning of the internal and external compositions was validated using various supporting data. The unique structured nanospheres with a configuration of FeO x -C@void@C showed an excellent lithium-ion storage performance. [ABSTRACT FROM AUTHOR]

• 3D network structure g-C 3 N 4 assembled by nanorods (3D g-C 3 N 4 NR) was fabricated via a chemical tailoring route. • 3D g-C 3 N 4 NR increases the specific surface area and accelerates the charge carrier transfer kinetics. • The visible-light photocatalytic performance of 3D g-C 3 N 4 NR has been greatly improved. Bulk g-C 3 N 4 has suffered from its low specific surface area and high recombination of photogenerated electron-hole pairs. Herein, three-dimensional network structure g-C 3 N 4 assembled by nanorods (3D g-C 3 N 4 NR) was successfully fabricated via a chemical tailoring route. The as-prepared 3D g-C 3 N 4 NR exhibits lager specific surface areas (6.7 times of bulk g-C 3 N 4) and faster charge carrier transfer kinetics. Hence, the visible-light photocatalytic activities for degradation of phenol and hydrogen evolution over 3D g-C 3 N 4 NR are evidently enhanced, 4.3 and 5.9 times as high as that of bulk g-C 3 N 4 , respectively. Briefly, this work throws light on structural tuning of carbon nitride polymer photocatalysts for improved solar energy capture and conversion. [ABSTRACT FROM AUTHOR]

Abstract We demonstrate design of Cu/Mo nanocomposite thin films with bicontinuous intertwined morphologies for high strength and plastic deformability. Through co-sputtering Cu and Mo at different temperatures, nanocomposites with lateral and random concentration modulations (LCMs and RCMs) were fabricated. Ligament size and coherency of the Cu/Mo interfaces was also controlled via the deposition conditions. It was discovered that nanocomposites with LCM structure and coherent interfaces have high strength but limited deformability. Enhanced deformability was achieved when the interface was altered to semi-coherent, although plasticity was localized in kink bands. The RCM structure design with semi-coherent interfaces showed an excellent combination of high flow strength and plastic deformability due to suppression of shear and kink bands. Graphical abstract Unlabelled Image Highlights • A novel approach in addressing the strength-deformability trade-off through morphological and interface design in metallic nanocomposites is presented. • Cu-Mo nanocomposites with tailorable morphology and interface properties have been fabricated by co-sputtering two immiscible metals at high temperatures. • The bicontinuous intertwined with semi-coherent Cu-Mo interfaces provides an unprecedented combination of high strength and enhanced plastic deformability. [ABSTRACT FROM AUTHOR]

Superhydrophobic (SHPo) surfaces can provide high condensation heat transfer due to facilitated droplet removal. However, such high performance has been limited to low supersaturation conditions due to surface flooding. Here, we quantify flooding resistance defined as the rate of increase in the fraction of water-filled cavities with respect to the supersaturation level. Based on the quantitative understanding of surface flooding, we suggest effective anti-flooding strategies through tailoring the nanoscale coating heterogeneity and structure length scale. Experimental verification is conducted using CuO nanostructures having different length scales combined with hydrophobic coatings with different nanoscale heterogeneities. The proposed anti-flooding SHPo can provide a ∼130% enhanced average heat transfer coefficient with ∼14% larger supersaturation range for droplet jumping compared to a previous CuO SHPo. The proposed anti-flooding parameter and the scalable SHPo will help develop high-performance condensers for real-world applications operating in a wide range of supersaturation levels.

The poor durability of bifunctional oxygen electrocatalysts is one main bottleneck that suppresses the widespread application of rechargeable metal-air batteries. Herein, a "ship in a bottle" design is achieved by impregnating fine transition metal dichalcogenide nanoparticles into defective carbon pores that act as interconnected nanoreactors. The erected 3D porous conductive architecture provides a "highway" for expediting charge and mass transfer. This design not only delivers a high surface-to-volume ratio to increase numbers of exposed catalytic sites but also precludes nanoparticles from aggregation during cycling owing to the pore spatial confinement effect. Therefore, the long-term plague inherent to nanocatalyst stability can be solved. Moreover, the synergistic coupling effects between defect-rich interfaces and chemical bonding derived from heteroatom-doping boost the catalytic activity and prohibit the detachment of nanoparticles for better stability. Consequently, the developed catalyst presents superior bifunctional oxygen electrocatalytic activities and durability, out-performing the best-known noble-metal benchmarks. In a practical application to rechargeable Zn-air batteries, long-term cyclability for over 340 h is realized at a high current density of 25 mA cm -2 in ambient air while retaining an intact structure. Such a universal "ship in a bottle" design offers an appealing and instructive model of nanomaterial engineering for implementation in various fields.