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Continuous 3D hierarchical construction has been proved to serve as a feasible method to prepare high-efficiency microwave absorption (MA) composites. Herein, an innovative hierarchical carbon fiber (CF)@MXene@ZnO core-sheath synergistic structure with tunable and efficient MA performance has been synthesized via a self-assembly (MXene) and hydrothermal (ZnO) process. Because of increased conductivity loss of the interlayer MXene sheath due to synergistic effects and the enhanced impedance matching of the outer ZnO layer, the optimal reflection loss (RL) value of CMZ2 is −67.35 GHz at 9.0 GHz at a thickness of 3.5 mm and the optimal effective absorption bandwidth (EAB) is 5.44 GHz, covering the full X band at a thickness of 4.0 mm. Furthermore, the CMZ microrods can be used as energy transformers and molecular heaters due to the synergistic effects of the high photothermal conversion efficiency of MXene, high photocatalytic activity of ZnO, and high thermal conductivity of CF. When used as wearable CMZ/polyurethane (PU) composite coatings, the surface temperature increases rapidly with a healing efficiency of above 91% for mechanical damage. These results provide a new strategy to fabricate wearable materials with effective MA and photothermal properties for designing safe and wearable devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Softening of piezoelectric materials facilitates the development of flexible wearables and energy harvesting devices. However, as one of the most competitive candidates, piezoelectric ceramic-polymer composites inevitably exhibit reduced power-generation capability and weak mechanical strength due to the mismatch of strength and permittivity between the two phases inside. Herein a flexible, air-permeable, and high-performance piezoceramic textile composite with a mechanically reinforced hierarchical porous structure is introduced. Based on a template-assisted sol-gel method, a three-order hierarchical ceramic textile is constructed by intertwining submillimeter-scale multi-ply ceramic fibers that are further formed by twisting micrometer-scale one-ply ceramic fibrils. Theoretical analysis indicates that large mechanical stress can be easily induced in the multi-order hierarchical structure, which greatly benefits the electrical output. Fabricated samples generate an opencircuit voltage of 128 V, a short-circuit current of 120 μA, and an instantaneous power density of 0.75 mW cm-2, much higher than the previously reported works. The developed multi-order and 3D-interconnected piezoceramic textile shows satisfactory piezoelectricity (d33 of 190 pm V-1), air permeability (45.1 mm s-1), flexibility (Young's modulus of 0.35 GPa), and toughness (0.125 MJ m-3), collectively. The design strategy of obtaining balanced properties promotes the practicality of smart/functional materials in wearables and flexible electronics. [ABSTRACT FROM AUTHOR]

A three‐dimensional real‐space model has been created for hierarchical materials by matching observed and simulated small‐angle X‐ray scattering patterns. The simulation is performed by arranging the positions of small primary particles and constructing an aggregate structure in a finite‐sized cell. In order to avoid the effect of the finite size of the cell, the cell size is extended to infinity by introducing an asymptotic form of the long‐range correlations among the primary particles. As a result, simulations for small‐angle X‐ray scattering patterns can be performed correctly in the low‐wavenumber regime (<0.1 nm−1), allowing the model to handle hundred‐nanometre‐scale structures composed of primary particles of a few nanometres in size. An aerogel structure was determined using this model, resulting in an excellent match with the experimental scattering pattern. The resultant three‐dimensional model can generate cross‐sectional images similar to those obtained by transmission electron microscopy, and the calculated pore‐size distribution is in accord with that derived from the gas adsorption method. [ABSTRACT FROM AUTHOR]

Transition metal selenides (TMSes) are regarded as ideal anode materials for lithium‐ion batteries (LIBs) due to their high theoretical capacity, but some defects, such as volume expansion and poor conductivity, still need to be overcome. The design of hierarchical structural materials with compositional and structural complexity is extremely attractive in the field of energy conversion. Herein, a core–shell hierarchical polyhedral Co3Se4 with N‐doped and carbon nanotubes intertwined (N‐Co3Se4@C‐CNTs) is synthesized using a facile metal–organic framework (MOFs) self‐templating strategy and selenization treatment. The Co3Se4 nanoparticles can be confined in the multilocular and hollow carbon framework intertwined with CNTs. Benefiting from the unique structure and composition superiority, the synthesized N‐Co3Se4@C‐CNTs exhibit excellent Li storage performance. Specifically, they present a high reversible capacity of 820 mAh g−1 at 0.1 A g−1 after 100 cycles and outstanding cycling stability (558 mAh g−1 at 2 A g−1 after 1000 cycles). In addition, a LiCoO2‖N‐Co3Se4@C‐CNT full cell is successfully constructed to show its potential for practical application. The reaction kinetics and Li storage mechanisms of the N‐Co3Se4@C‐CNT electrode are investigated to explain the impressive electrochemical performance. This work reveals the great application potential of the N‐Co3Se4@C‐CNT electrode in constructing advanced LIBs. [ABSTRACT FROM AUTHOR]

Pressure sensitivity and wide range are two crucial features of flexible electromechanical sensors for applications in the next‐generation of intelligent electronics, such as wearable healthcare monitors and soft human–machine interfaces. Conventional pressure sensors have a narrow pressure range (

Abstract Two frontier crystalline porous framework materials, namely, metal‐organic frameworks (MOFs) and covalent organic frameworks (COFs), have been widely explored owing to their outstanding physicochemical properties. While each type of framework has its own intrinsic advantages and shortcomings for specific applications, combining the complementary properties of the two materials allows the engineering of new classes of hybrid porous crystalline materials with properties superior to the individual components. Since the first report of MOF/COF hybrid in 2016, it has rapidly evolved as a novel platform for diverse applications. The state‐of‐art advances in the various synthetic approaches of MOF/COF hybrids are hereby summarized, together with their applications in different areas. Perspectives on the main challenges and future opportunities are also offered in order to inspire a multidisciplinary effort toward the further development of chemically diverse, multi‐functional hybrid porous crystalline materials.

In this paper, NiO, La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) and (CeO2)0.8(Sm2O3)0.2 (SDC) nanopowders with different microstructures were obtained using hydrothermal and glycol–citrate methods. The microstructural features of the powders were examined using scanning electron microscopy (SEM). The obtained oxide powders were used to form functional inks for the sequential microextrusion printing of NiO-SDC, SDC and LSCF-SDC coatings with resulting three-layer structures of (NiO-SDC)/SDC/(LSCF-SDC) composition. The crystal structures of these layers were studied using an X-ray diffraction analysis, and the microstructures were studied using atomic force microscopy. Scanning capacitance microscopy was employed to build maps of capacitance gradient distribution over the surface of the oxide layers, and Kelvin probe force microscopy was utilized to map surface potential distribution and to estimate the work function values of the studied oxide layers. Using SEM and an energy-dispersive X-ray microanalysis, the cross-sectional area of the formed three-layer structure was analyzed—the interfacial boundary and the chemical element distribution over the surface of the cross-section were investigated. Using impedance spectroscopy, the temperature dependence of the electrical conductivity was also determined for the printed three-layer nanostructure.

Many aquatic creatures in nature have non-cooperative surface scaling abilities using suction organs; micro-/nano-scale structures found in different parts of the organs play an important role in this mechanism. Synthetic bioinspired suction devices have been developed, but the mechanisms of bioinspired suction system need further investigation. This paper presents the development of a synthetic adhesive disc inspired by the hillstream loach. The microscopic structures involved in adhesion of the hillstream loach were investigated. Bioinspired suction discs were designed with single-level or hierarchical micropatterned margins. Micro three-dimensional (3D) printing and micro electromechanical system (MEMs) technology were utilized in the fabrication of the discs, and the adhesion performance was tested on substrates with different roughness values. The engaging and disengaging processes of the margin were simulated by carrying out a peeling test on a submerged substrate. The interactions between the liquid film and the microstructures were observed using fluorescence microscopy. The enhanced adhesion forces due to the synergy of the hierarchically micro-patterned margin and the disc cavity were duplicated in the synthetic adhesion system.

One of the major challenges regarding the sulfur cathode of Li‐S batteries is to achieve high sulfur loading, fast Li ions transfer, and the suppression of lithium polysulfides (LiPSs) shuttling. This issue can be solved by the development of molybdenum carbide decorated N‐doped carbon hierarchical double‐shelled hollow spheres (Mo2C/C HDS‐HSs). The mesoporous thick inner shell and the central void of the HDS‐HSs achieve high sulfur loading, facilitate the ion/electrolyte penetration, and accelerate charge transfer. The microporous thin outer shell suppresses LiPSs shuttling and reduces the charge/mass diffusion distance. The double‐shelled hollow structure accommodates the volume expansion during lithiation. Furthermore, Mo2C/C composition renders the HDS‐HSs cathode with improved conductivity, enhanced affinity to LiPSs, and accelerated kinetics of LiPSs conversion. The structural and compositional advantages render the Mo2C/C/S HDS‐HSs electrode with high specific capacity, excellent rate capability, and ultra‐long cycling stability in the composed Li‐S batteries. [ABSTRACT FROM AUTHOR]

Engineered systems are typically based on a large variety of materials differing in composition and processing to provide the desired functionality. Nature, however, has evolved materials that are used for a wide range of functional challenges with minimal compositional changes. The exoskeletal cuticle of spiders, as well as of other arthropods such as insects and crustaceans, is based on a combination of chitin, protein, water and small amounts of organic cross-linkers or minerals. Spiders use it to obtain mechanical support structures and lever systems for locomotion, protection from adverse environmental influences, tools for piercing, cutting and interlocking, auxiliary structures for the transmission and filtering of sensory information, structural colours, transparent lenses for light manipulation and more. This paper illustrates the 'design space' of a single type of composite with varying internal architecture and its remarkable capability to serve a diversity of functions. This article is part of the theme issue 'Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 1)'. [ABSTRACT FROM AUTHOR]

[Display omitted] • Enhanced PCE under indoor light and full sun without affecting transparency. • PCE of 15.5% achieved under indoor illumination (1000 lux, CFL). • PCE improvement of 40% and 44% upon front and back illumination. • Enhanced LHE, as well as η cc , contributed to better J sc and PCE. • A novel strategy for enhancing PCE of bifacial DSSCs for BIPV applications. We have already demonstrated a facile strategy for improving light scattering in bifacial dye sensitized solar cells (DSSCs) through fugitive inclusions of ZnO micro-flowers leading to enhanced photovoltaic performance without adversely affecting the transparency (Sasidharan et al., 2020). In the present work, we were able to further ameliorate the light scattering properties by employing micron sized ZnO hierarchical structures (fibril and sheet like aggregates) as sacrificial inclusions. ZnO hierarchical structures being deposited over TiO 2 active layer were selectively etched off, leaving behind imprints over the TiO 2 layer, which act as scattering centers to enhance the photocurrent of DSSCs owing to the increased light absorption. The present strategy extends the possibility to improve the performance of DSSCs under both one sun (100 mW/cm2) as well as indoor/ambient light conditions without compromising transparency to larger extend. By employing this strategy on a 6 µm thick TiO 2 photoanode and implementing it in a DSSC using N719 sensitizer and iodide/triiodie electrolyte, power conversion efficiency of 15.5% could be achieved under indoor illumination (1000 lx) from a compact fluorescent lamp. A detailed study of the charge transfer dynamics at various interfaces were carried out using a range of electrical and optical perturbation techniques. [ABSTRACT FROM AUTHOR]

Adaptive materials with tunable superhydrophobic surfaces promise to impact a range of fluid handling technologies; however, adaptive superhydrophobic materials remain difficult to fabricate, control, and switch rapidly. Here, a versatile method for generating hierarchically structured and adaptive superhydrophobic silicone films for the rational control of surface wettability and droplet adhesion is reported. Specifically, mechanical tension is utilized to manipulate networks of microcracks in nanoporous layers supported on elastomeric silicone films, enabling dynamic modulation of superhydrophobicity and droplet adhesion. The reported mechano‐responsive superhydrophobic surfaces are applied to directional droplet shedding and "no‐loss" droplet transport and are used to generate artificial "skins" with droplet tweezing capabilities. This approach provides materials with enhanced functionality useful to a range of emergent technologies, including adaptive textiles, biocompatible (wearable) sensors, soft robotics, anti‐icing systems, "no‐loss" droplet manipulators, and thermal management devices. [ABSTRACT FROM AUTHOR]

By introducing metallic ring structural dipole resonances in the microwave regime, we have designed and realized a metamaterial absorber with hierarchical structures that can display an averaged -19.4 dB reflection loss (~99% absorption) from 3 to 40 GHz. The measured performance is independent of the polarizations of the incident wave at normal incidence, while absorption at oblique incidence remains considerably effective up to 45°. We provide a conceptual basis for our absorber design based on the capacitive-coupled electrical dipole resonances in the lateral plane, coupled to the standing wave along the incident wave direction. To realize broadband impedance matching, resistive dissipation of the metallic ring is optimally tuned by using the approach of dispersion engineering. To further extend the absorption spectrum to an ultrabroadband range, we employ a double-layer self-similar structure in conjunction with the absorption of the diffracted waves at the higher end of the frequency spectrum. The overall thickness of the final sample is 14.2 mm, only 5% over the theoretical minimum thickness dictated by the causality limit. [ABSTRACT FROM AUTHOR]

Electrochemical energy storage is a key technology for a clean and sustainable energy supply. In this respect, supercapacitors (SC) have recently received considerable attention due to their excellent performance, including high‐power density and long‐cycle life. However, the poor binding strength between the active materials and substrate, the low active material loading, and small specific capacitance hinder the overall performance improvement of the device. In this study, an ultrahigh‐areal capacitance flexible SC based on the Al micro grid‐based hierarchical vertically aligned carbon nanotubes (VACNTs) is studied. Interestingly, the Al micro grid‐based VACNTs exhibit ultrahigh loading (13 mg cm−2), and the as‐fabricated VACNTs electrode display outstanding electrochemical performance, including an impressive areal capacitance of 1,300 mF cm−2 at the current density of 13 mA cm−2 and excellent stability with a retention ratio of 90% after 20,000 cycles at the current density of 130 mA cm−2. Furthermore, the hierarchical VACNT electrodes show excellent mechanical flexibility when assembled into quasi‐solid‐state SC using Na2SO4‐PVA gel as the electrolyte. The capacitance of this device is hardly changed bending different angles, even 180°. This study demonstrates the tremendous potential of Al micro grid‐based hierarchical VACNTs as electrodes for high‐performance flexible and wearable energy storage devices. [ABSTRACT FROM AUTHOR]

In recent years, there has been an increasing interest in the novel bioinspired sensors, especially for their selectivity, response time, and sensitivity. Particular attention is paid to the novel optical functional materials that are crucial for the sensors to achieve various energy transduction. Ideally, many critical parameters of the optical sensing materials can be appropriately tailored to meet various specific requirements using optimal design. Over a long and cruel evolution, nature's creatures have created a variety of photonic structures. One impressive example is the iridescent wings of butterfly. The natural photonic crystals on its surfaces have inspired diverse novel designs of optical functional sensing materials, especially in the past three years. Herein, this review mainly discusses recent advances of the burgeoning butterfly‐inspired sensing materials with optical properties that can be modulated in response to different external stimuli. First, their optical sensing performance to infrared radiation/thermal, vapor, liquid, pH, and so on are discussed in details. Then, the fabrication methods and their working mechanisms are also introduced. Furthermore, the general strategies of these emerging sensing materials and their potential applications are also discussed in‐depth as well as their limitations and the future challenges. [ABSTRACT FROM AUTHOR]

Room temperature sodium–sulfur (RT Na–S) batteries are considered a promising candidate for energy‐storage due to their high energy‐density and low‐cost. However, the shutting effect of polysulfides and sluggish kinetics of sulfur redox reactions still severely limit their practical implementation. Herein, a new type of 3D hierarchical porous carbonaceous nanocubes is reported as efficient sulfur hosts, composed of carbon nanotubes (CNT) and Co nanoparticles (NPs) uniformly embedded into a nitrogen‐doped carbon matrix (NC). Because of the high specific surface area, large degree of graphitization, and the synergetic effects between Co NPs and N‐doping, the as‐designed CNTs/Co@NC electrodes not only significantly increase polysulfides immobilization, but also efficiently catalyze sulfur redox reactions, as confirmed by experimental results and DFT calculations. When tested in a RT Na–S battery, the S@CNTs/Co@NC‐0.25 cathode demonstrates outstanding electrochemical performance, achieving high initial specific capacity of 1200.3 mAh g−1 at 0.1 C, remarkable rate capability up to 5.0 C (474.2 mAh g−1), and superior cyclic performance of 450.5 mAh g−1 (292 mAh g−1) after 400 cycles at 1.0 C (5.0 C). The integration of a 3D hierarchical porous architecture with well‐dispersed Co NPs of an electro‐catalyst provides valuable insights based on structure‐adsorption‐catalysis engineering for advanced RT Na–S batteries. [ABSTRACT FROM AUTHOR]

Hierarchical heterostructures have been proven to be the great material structures for the fabrication of gas sensors, due to they high surface area, well-aligned porosity and synergy effect. Here, ZnO hierarchical structures with various amount of Mn dopant were synthesized through a simple one-step solution route followed by annealing treatment. The characterization results demonstrated that Mn dopant existed in the forms of Mn 3 O 4 nanoparticles and lattice Mn2+ ions. The as-synthesized Mn 3 O 4 /ZnO hierarchical structures with abundant oxygen vacancies (Mn x ZnO with x values of 0, 0.25, 0.5, 1 and 3) were used as the sensing materials toward volatile organic compounds (VOCs) detection, illustrating that the introduction of Mn dopant can significantly improve the gas sensing performance. Especially, under optimal working temperature, Mn 0.5 ZnO hierarchical structures-based gas sensor exhibits the highest responses, fast response/recovery speed (2/9 s), a low detection limit (150 ppb), good selectivity and long-term stability toward acetone. In addition, the enhanced gas sensing mechanisms were explained by large surface area, oxygen vacancies and p-n heterojunction, boosting the surface reactions, which was further verified through DFT calculations. This work also confirmed that Mn element could be a promising dopant in metal oxides for high-performance VOCs gas sensors. [Display omitted] • Mn x ZnO hierarchical structures were synthesized through a simple solution route. • Mn 0.5 ZnO sensor exhibits high response, fast response/recovery speed, low detection limit toward acetone. • Sensing mechanisms were studied by large surface area, oxygen vacancies and p-n heterojunction. [ABSTRACT FROM AUTHOR]

• A physics-informed neural network is developed on thin film evaporation in hierarchical structures. • The model inputs are the geometrical features of the structure and properties of the working fluid. • The model has been trained and validated on a large dataset with excellent accuracy and has been further examined on two independent studies. • The model could provide heat flux curve of any hierarchical structure before manufacturing providing a new paradigm for discovery of structures for high-performance cooling systems. Miniaturization, consistent performance improvements in transistors, chips, smartphones, vehicle electronics, and server farms have led to high power density, increasing the demand for advanced cooling techniques. Various methods, including microchannels, sprays, and jet impingement, have been explored to manage thermal issues, with thin film evaporation gaining particular attention due to its potential for high heat flux applications. Extensive experimental studies have been conducted over the last two decades on thin film evaporation in hierarchical structures. However, the vast domain of possible geometrical configurations and cost of fabrication make it unfeasible to explore structure variations through experimental efforts. Here, we introduce a universally applicable Physics-informed Neural Network (PINN) platform to address this challenge and guide the discovery of hierarchical structures for efficient thermal management in high-performance photonics/electronics. The PINN platform was trained on an extensive experimental dataset covering various forms of hierarchical structures in thin film evaporation. It utilizes five geometrical dimensions of the structures and three dimensionless numbers governing heat transfer and fluid dynamics. Given the geometrical dimension and the type of working fluid, the PINN model could predict the heat flux curve with remarkable accuracy. The predictive PINN platform's performance was independently validated by two independent studies, making it a foundational tool for systematic exploration of various structures for high heat flux applications in electronics, hypersonic aviation, and electric vehicles. [ABSTRACT FROM AUTHOR]

Morphology profoundly influences nanomaterials' performance for various applications including energy, environment, and catalysis etc. Molybdenum disulfide, the most studied nanomaterial after graphene, has undergone intense research in this perspective, showing its potential for real-time applicability. The unique electronic structure and charge distribution make MoS 2 suitable for practicing various faceted controlled synthesis methods and exploring apposite application paths for each topographical structure. The most popular topographical structures include nanosheets, nanoflowers, nanoscrolls, nanoribbons, nanowires, wrinkled structures, nanotubes, nanospheres, and hierarchical structures. The present review presents a comprehensive collection of advents in specific morphology targeted synthesis of MoS 2 and the contribution of each morphology towards specific applications. [Display omitted] • Summarized the impact of morphology on the properties of morphologically diverse MoS 2 in various applications. • Summarized the importance of popular topological forms of MoS 2 in connection with specific high-end applications. • Discussed the direct influence of MoS 2 nanostructure morphologies ranging from 1D to 3D on their high-end applications. • Detailed the role of the morphology of MoS 2 nanostructures in applications ranging from environment to energy. • Shared the perspective on the challenges and opportunities of the morphology engineering design of MoS 2. [ABSTRACT FROM AUTHOR]

The article considers the possibilities of redesign of the organizational management structures in accordance with the current requirements of their construction (optimality, efficiency, reliability, flexibility, adaptability, sustainability, efficiency, etc.) to accomplish the mission and functions of universities, and to achieve their goals. Applying the latest methods of system analysis in management, the author on a number of criteria evaluates advantages and disadvantages of traditional and innovative, adaptive organizational structures of management of the modern University, more acceptable for the effective management of scientific and educational institutions.

Angiosperms and their pollinators are adapted in a close co-evolution. For both the plants and pollinators, the functioning of the visual signaling system is highly relevant for survival. As the frequency range of visual perception in many insects extends into the ultraviolet (UV) region, UV-patterns of plants play an important role in the flower–pollinator interaction. It is well known that many flowers contain UV-absorbing pigments in their petal cells, which are localized in vacuoles. However, the contribution of the petal surface microarchitecture to UV-reflection remains uncertain. The correlation between the surface structure and its reflective properties is also relevant for biomimetic applications, for example, in the field of photovoltaics. Based on previous work, we selected three model species with distinct UV-patterns to explore the possible contribution of the surface architecture to the UV-signaling. Using a replication technique, we transferred the petal surface structure onto a transparent polymer. Upon illumination with UV-light, we observed structural-based patterns in the replicas that were surprisingly comparable to those of the original petals. For the first time, this experiment has shown that the parameters of the surface structure lead to an enhancement in the amount of absorbed UV-radiation. Spectrophotometric measurements revealed up to 50% less reflection in the UV-absorbing regions than in the UV-reflecting areas. A comparative characterization of the micromorphology of the UV-reflecting and UV-absorbing areas showed that, in principle, a hierarchical surface structure results in more absorption. Therefore, the results of our experiments demonstrate the structural-based amplification of UV-reflection and provide a starting point for the design of bioinspired antireflective and respectively strongly absorbing surfaces.

Hierarchical silicon structures consisting of micropyramids and nanowire arrays are fabricated by two-step chemical etching processes aimed at achieving cost and time effectiveness constraints without using any expensive vacuum system or complicated lithography process. The hierarchical structures can suppress the average reflectance to as low as 4.3% from 300 to 1100 nm without causing poor minority carrier lifetimes, exhibiting excellent broadband light-harvesting abilities with minimal recombination losses, which is the key point to design high-performance nanostructured solar cells. By utilizing hierarchical structures in the practical solar cells application, the short-circuit current density (JSC) shows a significant enhancement from 21.5 to 28.7 mA/cm2, and the conversion efficiency is enhanced by a factor of 35%. Such a significant enhancement is attributed not only to the superior light harvesting achieved by hierarchical structures but also to the benefit of small electrical losses in the solar cells. Thus, the concept and technique presented in this paper open avenues for developing high-performance structure solar devices.

Stabilizing the hydrophobic wetting state on a surface is essential in heat transfer and microfluidics. However, most hydrophobic surfaces of Si are primarily achieved through microtexturing with subsequent coating or modification of low surface energy materials. The coatings make the hydrophobic surface unstable and impractical in many industrial applications. In this work, the Si chips’ wettability transitions are yielded from the original hydrophilic state to a stable transitional hydrophobic state by texturing bamboo-leaf-like hierarchical structures (BLHSs) through a diamond grinding wheel with one-step forming. Experiments showed that the contact angles (CAs) on the BLHS surfaces increased to 97° and only reduced by 2% after droplet impacts. This is unmatched by the current texturing surface without modification. Moreover, the droplets can be split up and transferred by the BLHS surfaces with their 100% mass. When the BLHS surfaces are modified by the low surface energy materials’ coating, the hydrophobic BLHS surfaces are upgraded to be superhydrophobic (CA > 135°). More interestingly, the droplet can be completely self-sucked into a hollow micro-tube within 0.1 s without applying external forces. A new wetting model for BLHS surfaces based on the fractal theory is determined by comparing simulated values with the measured static contact angle of the droplets. The successful preparation of the bamboo-leaf-like Si confirmed that transitional wettability surfaces could be achieved by the micromachining of grinding on the hard and brittle materials. Additionally, this may expand the application potential of the key semiconductor material of Si.

Exploring non‐precious metal‐based electrocatalysts at high current density and stability is an urgent issue for sustainable H2 production. Here, hierarchical core‐shell N‐doped carbon encapsulated array‐like FeP4 and CoP active components have been fabricated in situ on the surface of nickel foam (NC@FeP4‐CoP/NF) by etching sheet‐like ZIF‐67 arrays, Prussian analog formation, and phosphating in turns. The crystallinity, hierarchical heterostructure, and chemical state have been carefully discussed. Electrochemical studies demonstrate that the catalyst displays excellent electrocatalytic activity and durability in electrochemical oxygen evolution reaction (η20 = 218 mV) and hydrogen evolution reaction (η10 = 116 mV), better than most previously reported bifunctional catalysts. Moreover, the bifunctional catalyst only needs 1.72 and 1.80 V cell voltages at 500 and 1000 mA cm−2 respectively, together with a good catalytic stability at 500 mA cm−2 for 48 h, implying potential commercialization prospects. This excellent electrocatalytic performance is mainly attributed to the distinctive hierarchical structure as well as core‐shell NC encapsulated FeP4‐CoP active sites, which can enhance the charge transport rate, inhibit the exfoliation of the active materials, provide a larger active surface area, and facilitate electrolyte diffusion and gas release. [ABSTRACT FROM AUTHOR]

The serious shuttle effect, sluggish reduction kinetics of polysulfides and the difficult oxidation reaction of Li2S have hindered LiS battery practical application. Herein, a 3D hierarchical structure composed of NiMoO4 nanosheets in situ anchored on NS doped carbon clothes (NiMoO4@NSCC) as the free‐standing host is creatively designed and constructed for LiS battery. Dual transitional metal oxide (NiMoO4) increases the electrons density near the Fermi level due to the contribution of the incorporating molybdenum (Mo), leading to the smaller bandgap, and thus stronger metallic properties compared with NiO. Furthermore, as a bidirectional catalyst, NiMoO4 is proposed to facilitate reductions of polysulfides through lengthening the SS bond distance of Li2S4 and reducing the free energy of polysulfides conversion, meanwhile promote critical oxidation of insulative discharge product (Li2S) via lengthening LiS bond distance of Li2S and decreasing Li2S decomposition barrier. Therefore, after loading sulfur (2 mg cm−2), NiMoO4@NSCC/S as the self‐supporting cathode for the LiS battery exhibits impressive long cycle stability. This study proposes a concept of a bidirectional catalyst with dual metal oxides, which would supply a novel vision to construct the high‐performance LiS battery. [ABSTRACT FROM AUTHOR]

Efficient light‐harvesting is of significant importance to achieve high solar energy utilization efficiency for various solar‐driven technologies. Compared with a 2D planar structure, a 3D plasmonic structure can largely increase the light adsorption/interaction areas and also utilizes the plasmonic effect to achieve much higher light utilization efficiency. However, this remains challenging in terms of structural design, reliable manufacturing, and ability to scale up. Herein, inspired by the light absorption strategy of natural forests, a hierarchical plasmonic superstructure is demonstrated composed of vertical TiO2 pillar arrays (as tree trunks), dense nanorod arrays (as branches), and a large number of plasmonic Au nanoparticles (as leaves). Such a forest‐like plasmonic superstructure can effectively absorb light from the surface plasmonic resonance effects of Au nanoparticles and the multiple scattering of light in the hierarchical branched structure. The strong light absorption and abundant photocatalytic active sites help yield a 15‐fold higher nitrogen photo‐fixation activity than that of the flat TiO2 films decorated with Au nanoparticles. The study provides an effective strategy to construct 3D plasmonic superstructures with excellent light‐harvesting efficiency and high stability and can be readily applied to a range of light‐driven applications [ABSTRACT FROM AUTHOR]

Interfacial surfaces with hierarchical structures have triggered intense research interest and been used in a broad range of applications ranging from anti‐icing, anti‐fogging, surface‐enhanced Raman spectroscopy to catalytic reaction. However, the high‐cost manufacturing processes and the limited durability remain as great challenges that need to be addressed, especially for superhydrophobicity. In this work, a novel hybrid approach for stretchable, transparent, and robust superhydrophobic surfaces is proposed, constructing micro‐pyramid architectures with tunable hierarchical wrinkles efficiently and in an environmentally friendly manner. Due to the multiscale structures, excellent superhydrophobicity is obtained with contact angle of ≈172° and sliding angle ≈5° in a steady "Lotus" state. Further, the wear resistance and stability tests also suggest a superior performance under simulated severe real‐world applications. Utilizing such multiscale synergistic co‐operation effects can be an excellent manufacturing strategy and be extended to other surface engineering where hierarchical architectures are needed. [ABSTRACT FROM AUTHOR]

The design of catalysts with high activity, selectivity, and stability is key to the electroreduction of CO2. Herein, we report the synthesis of 3D hierarchical metal/polymer–carbon paper (M/polymer‐CP) electrodes by in situ electrosynthesis. The 3D polymer layer on CP (polymer‐CP) was first prepared by in situ electropolymerization, then a 3D metal layer was decorated on the polymer‐CP to produce the M/polymer‐CP electrode. Electrodes with different metals (e.g. Cu, Pd, Zn, Sn) and various polymers could be prepared by this method. The electrodes could efficiently reduce CO2 to desired products, such as C2H4, CO, and HCOOH, depending on the metal used. For example, C2H4 could be formed with a Faradaic efficiency of 59.4 % and a current density of 30.2 mA cm−2 by using a very stable Cu/PANI‐CP electrode in an H‐type cell. Control experiments and theoretical calculations showed that the 3D hierarchical structure of the metals and in situ formation of the electrodes are critical for the excellent performance. [ABSTRACT FROM AUTHOR]

The fabrication of amphiphobic materials requires a precise and complicated design, especially for 3D porous materials, and amphiphobic sponges have rarely been investigated. This paper describes the synthesis of a superhydrophobic and oleophobic silicone sponge (SS‐F) by simply building hierarchical structures, that is, introducing a secondary structure on the pore walls of a hydrophobic and oleophilic silicone sponge. This simple and efficient synthesis method is based on the thiol–ene click reaction. The uniform structure, composition, and hierarchical structures of SS‐F are confirmed. The results of the analyses show that the secondary microstructure improves liquid repellency, while the rough and porous surface design ensures durability. Thus, SS‐F exhibits good stability, and the amphiphobicity of the surface could withstand scalpel cutting, cyclic compression, extreme temperatures of 250 and −196 °C for 5 h, and long‐term storage in an ambient environment. Both its outer and inner surfaces show superhydrophobicity and oleophobicity, which restrict the ability of the adsorption of liquids, enabling its use in oil and water. The introduction of hierarchical structures paves a way for preparing other 3D porous materials. [ABSTRACT FROM AUTHOR]

Cellular structures (CSs) have been used extensively in recent years, as they offer a unique range of design freedoms. They can be deployed to create parts that can be lightweight by introducing controlled porous features, while still retaining or improving their mechanical, thermal, or even vibrational properties. Recent advancements in additive manufacturing (AM) technologies have helped to increase the feasibility and adoption of cellular structures. The layer-by-layer manufacturing approach offered by AM is ideal for fabricating CSs, with the cost of such parts being largely independent of complexity. There is a growing body of literature concerning CSs made via AM; this presents an opportunity to review the state-of-the-art in this domain and to showcase opportunities in design and manufacturing. This review will propose a novel way of classifying cellular structures by isolating their Geometrical Degrees of Freedom (GDoFs) and will explore the recent innovations in additively manufactured CSs. Based on the present work, the design inputs that are common in CSs generation will be highlighted. Furthermore, the work explores examples of how design inputs have been used to drive the design domain through various case studies. Finally, the review will highlight the manufacturability limitations of CSs in AM. [ABSTRACT FROM AUTHOR]

Silk fibroin (SF) material receives a great deal of attention in the biomedical field for its extensive mechanical performance and applications due to its singular structure/properties and applications, especially hierarchical structure. Here, we blended polyethylene glycol (PEG) into SF solutions that reconstruct the hierarchical micro structure of SF. The effect of PEG on the SF gelation process was in situ observed through rheological measurement and optical density changes. The structural change of SF/PEG blended films with different concentrations and their effects on the mechanical performance were investigated. The results indicated that with increasing PEG content, the β-sheet content of the films increased with the α-helix declining, which enables a composite film with a fracture strain exceeding 300%, Young's modulus exceeding 200 MPa and a fracture strength exceeding 20 MPa. The culture of MC-3T3 proves that the film is beneficial for cell proliferation and adhesion. By constructing the mesoscopic structure of SF, the plasticized silk materials provide great options for biodegradable and flexible protein-based materials. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction into clean chemical fuels using visible light remains an enormous challenge. Construction of hierarchical heterostructured photocatalysts has gained tremendous popularity due to their distinctive structural characteristics and synergetic effect that they can boost the visible‐light photoactivities. Based on this, a three‐step solvothermal method is proposed to construct hierarchical BiOI/MoS2/CdS heterostructured microspheres. The addition of MoS2 and CdS not only plays a significant role in the improvement of visible‐light absorption, but also works as a carrier electron mediator, inhibiting the recombination of electrons–holes effectively. High CH4 yield (46.22 μmol h−1 g−1) and CO yield (36.98 μmol h−1 g−1) are achieved for BiOI/MoS2/CdS‐0.03 heterostructured microspheres under simulated sunlight irradiation because of the wide solar light‐driven response, abundant active sites and high charge separation ability. Therefore, this study provides an efficient strategy for constructing heterostructured catalysts with remarkable visible‐light response photocatalytic CO2 reduction activity. [ABSTRACT FROM AUTHOR]

Useful materials and energies from given materials including petroleum, minerals, biomass, and solar lights are obtained through various conversions. In most cases, efficient and specific conversions are supported by catalysts. Especially, nanotechnological structural analyses and regulation are important subjects in research approaches for advanced catalysts. Catalyst fabrication and functions based on atomic‐ and nanoscale‐level nanoarchitectonics approach are introduced in this progress report. Some of them are categorized as a hot subject: single atom catalysts. In order to show generalities and possibilities of catalyst designs by nanolevel structural regulations, several nanoarchitected catalysts are first exemplified. In the following sections, hot topics on atomically controlled catalysts designs are discussed with classification of i) site‐arrangement nanoarchitectonics, ii) multiatom arrangement nanoarchitectonics, and iii) hierarchical nanoarchitectonics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Rapid ZSM-5 (with high hierarchy factor) synthesis was achieved with CTAB+ seed. • Crystallinity and pore morphology were strong functions of [CTA+]/[Na+] ratio. • The pore geometry changed from slit to ink-bottle-shaped pores with CTAB addition. • The bimodal pore size distribution was observed in all the CTAB-templated samples. • Ink bottle-shaped pores showed excellent activity compared to those with slit pores. In this study, the ZSM-5 zeolites with a high hierarchy factor were synthesized rapidly and tested for the furfural hydroxymethylation (FH) to 5-hydroxymethylfurfural (HMF). The effect of seeding techniques (STs) and templates (both soft (Cetrimonium bromide, CTAB) and hard (bio-sourced secondary template, BSST)) on the final zeolite properties were studied. A significant variation in crystallinity and morphology with the ST and type of seed was observed. The CTAB addition increased the hierarchy factor (H factor) by 3 times, and the implicit seeds decreased the hydrothermal time by 2 times. The zeolite yield, crystallinity, and pore geometry were a strong function of [CTA+]/[Na+] ratio. Slit and ink bottle-shaped pore morphologies were observed with only seed or seed + BSST and with seed + CTAB, respectively, and both exhibited the bimodal pore size distribution. The zeolites with ink bottle-shaped pores outperformed those with slit pores in the FH and showed the highest selectivity to HMF of 65%, at 34% furfural conversion. The zeolites with high H factor showed catalytic and structural stability up to 5 successive recycle runs. [ABSTRACT FROM AUTHOR]

Direct laser scribing, an advanced printing technique, has been recently developed to enable the carbonization of carbonaceous precursors in a rapid, precise, and cost‐effective manner. Herein, it is reported that metal−organic frameworks (MOFs) can be converted into patterned derived carbon with desired structural features using a CO2 infrared laser system. Metal species in MOFs play a key role in the morphology, porous structure, and crystallinity of the resulting laser‐induced products by studying six representative MOFs. Diverse features such as ordered porous structure and continuous network microstructure can be obtained in the laser‐induced MOF‐derived carbon, which is influenced by the melting and boiling points of metals and their magnetic and catalytic behaviors. Furthermore, a core–shell structured composite (MOF‐199@ZIF‐67) has been designed and prepared for the fabrication of 12‐interdigital electrodes derived from the composite by laser‐assisted printing. The as‐obtained electrodes with highly porous and hierarchical structure show an enhanced specific capacitance for micro‐supercapacitors (MSCs). This work provides a complementary heat treatment method to produce MOF‐derived carbon nanomaterials with desired structural features and patterns for MSCs and micro‐device‐related applications. [ABSTRACT FROM AUTHOR]

For advanced fibrosis, isoprene is a typical characteristic marker that could be used to quickly screen the population for chronic liver disease (CLD). To achieve trace detection of isoprene, different mol% Pt-decorated In 2 O 3 and pure In 2 O 3 samples were prepared with the commonly used hydrothermal method. The obtained characterization results show that the prepared Pt-decorated In 2 O 3 (1 mol%) sample had Pt nanoparticles uniformly attached to the surface of porous hierarchical In 2 O 3 nanosheets, and the specific surface area was 62.3 m2/g. Subsequently, these sensors based on Pt–In 2 O 3 and pure In 2 O 3 nanomaterials were prepared, and their response characteristics were studied. The results show that the response of 1 mol% Pt–In 2 O 3 to isoprene gas was significantly enhanced, and the optimal working temperature was 200 °C. The response of 1 mol% Pt–In 2 O 3 to 5 ppb and 5 ppm isoprene was approximately 3.2 times and 25.9 times that of pure In 2 O 3 , respectively. Meanwhile, the 1 mol% Pt-modified sample exhibited excellent selectivity for isoprene relative to other biomarkers (carbon monoxide, hydrogen, ethanol, and ammonia). The sensor shows good repeatability and long-term stability. Therefore, the developed 1 mol% Pt-decorated In 2 O 3 was expected to be applied as a gas-sensitive material for breath isoprene, which could be suitable for large-scale CLD rapid breath detection. [ABSTRACT FROM AUTHOR]

Bone was a crucial biological material for the evolution of large terrestrial organisms and is today essential for most of our daily activities and well-being. From an engineering perspective, this living material features highly desirable properties for modern load-bearing structures. It is made of abundant and environmental-friendly building blocks, which are combined into a tough and durable structure that can continuously modify itself to adapt to changes in the mechanical load imposed by the surroundings. In this review article, we compile and discuss scientific findings that allow us to understand bone as a complex system with properties that emerge from cell-mediated interactions of molecules and particles at multiple length scales. Analogous to other complex systems, such interactions lead to self-organization, hierarchical structures and adaptive behavior without the need of a central controlling unit. A rich range of physical, chemical and biological phenomena provide a framework for information to be generated and processed in this complex system. Understanding the interplay between such underlying phenomena and their emerging properties should help the diagnosis and treatment of bone-related medical conditions and might provide guidelines for the future development of more sustainable materials and engineering structures.

There is growing evidence that pillaring up a densely packed ultramicroporous two‐dimensional (2D) structure is an effective strategy to reduce their internal diffusion. Reliable pillaring paradigms, however, is rather challenging. Here we report a one‐pot multi‐component sequential assembly method for the preparation of a new self‐pillared 2D polymer and ultramicroporous carbon with integrated surface protrusions. The molecular level pillaring process is surprisingly fast, that is, in 10 min. The thickness of nanoplate edge and the density (roughness), angle as well as height of protrusions can be precisely tuned. Exemplified in coal bed methane purification/separation, this unique pillared 2D carbons exhibit a CH4/N2 selectivity up to 24 at a low CH4 partial pressure and two orders of magnitude faster CH4 diffusion kinetics than the commercial carbon molecular sieves. This solution synthesis methodology is generalizable for creation and fine tuning of pillared 2D heterostructures. [ABSTRACT FROM AUTHOR]

There is growing evidence that pillaring up a densely packed ultramicroporous two‐dimensional (2D) structure is an effective strategy to reduce their internal diffusion. Reliable pillaring paradigms, however, is rather challenging. Here we report a one‐pot multi‐component sequential assembly method for the preparation of a new self‐pillared 2D polymer and ultramicroporous carbon with integrated surface protrusions. The molecular level pillaring process is surprisingly fast, that is, in 10 min. The thickness of nanoplate edge and the density (roughness), angle as well as height of protrusions can be precisely tuned. Exemplified in coal bed methane purification/separation, this unique pillared 2D carbons exhibit a CH4/N2 selectivity up to 24 at a low CH4 partial pressure and two orders of magnitude faster CH4 diffusion kinetics than the commercial carbon molecular sieves. This solution synthesis methodology is generalizable for creation and fine tuning of pillared 2D heterostructures. [ABSTRACT FROM AUTHOR]

There is growing evidence that pillaring up a densely packed ultramicroporous two‐dimensional (2D) structure is an effective strategy to reduce their internal diffusion. Reliable pillaring paradigms, however, is rather challenging. Here we report a one‐pot multi‐component sequential assembly method for the preparation of a new self‐pillared 2D polymer and ultramicroporous carbon with integrated surface protrusions. The molecular level pillaring process is surprisingly fast, that is, in 10 min. The thickness of nanoplate edge and the density (roughness), angle as well as height of protrusions can be precisely tuned. Exemplified in coal bed methane purification/separation, this unique pillared 2D carbons exhibit a CH4/N2 selectivity up to 24 at a low CH4 partial pressure and two orders of magnitude faster CH4 diffusion kinetics than the commercial carbon molecular sieves. This solution synthesis methodology is generalizable for creation and fine tuning of pillared 2D heterostructures. [ABSTRACT FROM AUTHOR]

There is growing evidence that pillaring up a densely packed ultramicroporous two‐dimensional (2D) structure is an effective strategy to reduce their internal diffusion. Reliable pillaring paradigms, however, is rather challenging. Here we report a one‐pot multi‐component sequential assembly method for the preparation of a new self‐pillared 2D polymer and ultramicroporous carbon with integrated surface protrusions. The molecular level pillaring process is surprisingly fast, that is, in 10 min. The thickness of nanoplate edge and the density (roughness), angle as well as height of protrusions can be precisely tuned. Exemplified in coal bed methane purification/separation, this unique pillared 2D carbons exhibit a CH4/N2 selectivity up to 24 at a low CH4 partial pressure and two orders of magnitude faster CH4 diffusion kinetics than the commercial carbon molecular sieves. This solution synthesis methodology is generalizable for creation and fine tuning of pillared 2D heterostructures. [ABSTRACT FROM AUTHOR]

Magnetic field‐directed assemblies of magnetic nanoparticles (MNPs) in ferrofluids exhibit complex interconvertible metastable patterns and structures. Formally, ferrofluid patterns are unstable – they disappear when the magnetic field is removed. The present study shows that ferrofluid patterns can be "trapped" as kinetically stable structures that encode a surprising degree of morphological detail over nanometer to millimeter length scales. An external magnetic field is used to direct assembly of oleic acid‐decorated magnetite (Fe3O4) nanoparticles to make spike and labyrinthine patterns in volatile host solvents of heptane, octane and nonane. Solvent evaporation coupled with increases in sample magnetization drive pattern formation and its permanent recording. Use of a crosslinking siloxane polymer host yields remarkably different material responses. From the trapped states in both fluid systems, previously unreported hierarchies of order emerge in nanocomposite spike structures that also exhibit orientational and magnetic anisotropy. The possibility of designing hierarchical matter from initially uncorrelated MNPs is demonstrated by a directed solid‐state transformation of the magnetic nanocomposite; the spikes template memory of their origin onto the transformation products. [ABSTRACT FROM AUTHOR]

The rational design of highly efficient bifunctional electrocatalysts for water splitting is extremely urgent for application in sustainable energy conversion processes to alleviate the energy crisis and environmental pollution. In this work, through simple deposition of layered double hydroxides (LDH) on Co3O4/NF (NF=nickel foam) nanosheets arrays, hierarchical Co3+‐rich materials based on LDH‐Co3O4/NF are prepared as highly active and stable electrocatalysts for water splitting. The NiFe‐LDH‐Co3O4/NF demonstrates excellent electrochemical activity with an overpotential of 214 mV for the OER and an overpotential of 162 mV for the HER at 10 mA cm−2. Such a performance is attributed to the optimized electronic states with a high concentration of Co3+, which improves the intrinsic activity, and the sheet‐on‐sheet hierarchical structure, which increases the number of active sites. The unique synchronous design of both the architectural and electronic structure of nanomaterials can simultaneously accelerate the reaction kinetics and provide a more convenient charge transfer path. Therefore, the strategy reported herein may open a new pathway for the design of excellent electrocatalysts for water splitting. [ABSTRACT FROM AUTHOR]

Featured Application: The investigated composed particles are of interest for future applications for nanoparticle-based surface-enhanced Raman scattering (SERS) analytics and as components in plasmonic sensing, such as biomolecules. The presence of the polycationic macromolecule poly(diallyldimethylammonium chloride) (poly-DADMAC) has a strong effect on the shape and size of colloidal gold nanoparticles formed by the reduction of tetrachloroauric acid with ascorbic acid in aqueous solution. It slows down nanoparticle growth and supports the formation of nonspherical, partially highly fractal and hierarchical nanoparticle shapes. Four structural levels have been recognized from the near-spherical gold nanoparticles in the lower nanometer range over compact aggregates in the midnanometer range and flower and star-like particles in the submicron range up to larger filamentous aggregates. High-contrast scanning electron microscope (SEM) images show that single gold nanoparticles and clusters of them are connected by bundles of macromolecules in large aggregates. The investigation showed that a large spectrum of different nanoparticle shapes and sizes can be accessed by tuning the poly-DADMAC concentrations and their ratio to other reactants. The nanoassemblies with a very high specific surface area might be of interest for SERS and heterogeneous catalysis. [ABSTRACT FROM AUTHOR]