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The functionalization of zirconia surfaces by accurate and fast printing of periodical patterns embedding sub‐micrometric features is of great interest to many engineering fields and is yet to be explored. This study aims to assess the influence of the Direct Laser Interference Patterning processing parameters on the morphology and microstructure of zirconia surfaces using a 532 nm 10 ps‐pulsed laser source. Well‐defined linear structures with a period of 3 µm are successfully produced. Depending on the laser parameters, the structures are developed at or below the surface level, with higher depths (≈1 µm) being seen for increasing values of laser fluence and pulse overlap. Line‐like hierarchical structures with smaller interference spatial structures (3 µm period) and higher secondary structures with different periods (18, 15, and 12 µm) and heights (7, 5, and 3 µm, respectively) are also obtained on zirconia surface. Ablated regions presented few traces of molten material, nano‐droplets, and sub‐micrometric (<1 µm) pores, while no (sub) micrometric cracks are detected. A slight amount of tetragonal to monoclinic phase transformation (≈5%) is detected by X‐ray diffractometry. A processability map for ps‐laser processing of zirconia is proposed based on the experimental data. [ABSTRACT FROM AUTHOR]

Thermoplastic elastomers (TPEs) are nanostructured, melt‐processable, elastomeric block copolymers. When TPEs that form cylindrical or lamellar nanostructures are macroscopically oriented, their material properties can exhibit several orders of magnitude of anisotropy. Here it is demonstrated that the flows applied during the 3D printing of a cylinder‐forming TPE enable hierarchical control over material nanostructure and function. It is demonstrated that 3D printing allows for control over the extent of nanostructural and mechanical anisotropy and that thermal annealing of 3D printed structures leads to highly anisotropic properties (up to 85 × anisotropic tensile modulus). This approach is leveraged to print functional soft 3D architectures with tunable local and macroscopic mechanical responses. Further, these printed TPEs intrinsically achieve melt‐reprocessability over multiple cycles, reprogrammability, and robust self‐healing via a brief period of thermal annealing, enabling facile fabrication of highly tunable, robust, and recyclable soft architectures. [ABSTRACT FROM AUTHOR]

Healthcare textiles serve as key reservoirs for pathogen proliferation, demanding an urgent call for innovative interventions. Here, a new class of Smart Fabrics (SF) is introduced with integrated "Repel, Kill, and Detect" functionalities, achieved through a blend of hierarchically structured microparticles, modified nanoparticles, and an acidity‐responsive sensor. SF exhibit remarkable resilience against aerosol and droplet‐based pathogen transmission, showcasing a reduction exceeding 99.90% compared to uncoated fabrics across various drug‐resistant bacteria, Candida albicans, and Phi6 virus. Experiments involving bodily fluids from healthy and infected individuals reveal a significant reduction of 99.88% and 99.79% in clinical urine and feces samples, respectively, compared to uncoated fabrics. The SF's colorimetric detection capability coupled with machine learning (96.67% accuracy) ensures reliable pathogen identification, facilitating accurate differentiation between healthy and infected urine and fecal contaminated samples. SF holds promise for revolutionizing infection prevention and control in healthcare facilities, providing protection through early contamination detection. [ABSTRACT FROM AUTHOR]

The emerging concept of aerogel composite phase change materials (PCMs) represents a promising approach for thermal energy storage and utilization. However, the thermal storage aerogels currently reported usually lack essential aerogel properties, thereby constraining their potential for functional design and advanced applications. Herein, multifunctional thermal storage aerogels with aerogel characteristics and thermoregulation performance are prepared by chemically crosslinking and unidirectional freezing to make functionalized mineral‐based composite PCMs as cavity walls. Thanks to the cross–linked continuous skeleton and retained hierarchical porous, this novel thermal storage aerogel possesses an 89.7% porosity and demonstrates excellent resilience under 80% compression. As the PCMs in the cavity walls can convert phonon transport modes through phase transitions, the thermal storage aerogel has enhanced thermal insulation properties, reaching a thermal conductivity of 29.6 mW m−1 K−1. Drawing upon the multifunctional properties of thermal storage aerogels, it is demonstrated that thermal storage masks with thermal comfort and health protection, as well as passive thermal management wrist guards capable of harnessing solar radiation for temperature regulation. This work encompasses the exploration of novel approaches in developing advanced thermal management materials to cater to the diverse thermal regulation requirements of PCMs across various domains. [ABSTRACT FROM AUTHOR]

Enhancing interfacial adhesion between functional coatings and target surfaces facilitates long‐term stable service by mitigating interferences of mechanical mismatches. Design of mechanical interlocks affords an effective strategy to strengthen the interfacial bonding with durability and compatibility, but the in‐depth investigations are still lacked. Herein, a gecko‐inspired hierarchical strategy realized by hybrid laser direct writing is proposed, which incorporates an armored frame scale for surface protection and a riveted anchor scale for interlocks. Such dual‐scale configurations endow the functional coatings with the stronger adhesion to the targets than the pristine and mono‐scale cases, resulting in 2 orders of magnitude enhancement resistant to tape peeling tests. Utilizing this scheme, a laser‐induced integrated deicing system is in situ manufactured on thermoplastics, primarily comprising superhydrophobic structures, carbon‐based sensors as well as adhesive copper (Cu) interconnects and heaters, where Cu‐based devices exhibit superior resistance to water impacts and stress fatigue. Interfacing with signal processing modules, such an all‐in‐one system demonstrates real‐time temperature monitoring and high efficiency in deicing (4.24 folds faster than the control group). The facile route for intensified adhesion holds promise in the interfaces within advanced equipment and under harsh scenarios. [ABSTRACT FROM AUTHOR]

Conductive hydrogels possessing high conductivity, stretchability, and biocompatibility are promising materials for underwater devices and bioelectronics. However, typical hydrogels often exhibit low electrical conductivity, which is insufficient for applications requiring high electronic communication. A common approach to increase hydrogel conductivity is to introduce conductive fillers; however, this usually implies a partial sacrifice of stretchability, biocompatibility, and water content. In addition, the electrical properties of hydrogels tend to be unstable due to rehydration in aqueous environments. In this study, a conductive hydrogel composite is fabricated from silver nanowires (AgNWs) and poly(vinyl alcohol) (PVA) employing a synergistic method of freezing and salting‐out treatments. This combined method constructs a hierarchical hydrogel structure and increases the local concentration of AgNWs by inducing continuous phase separation. The resultant conductive hydrogel composites exhibit ultra‐high electrical conductivity (≈1739 S cm−1) and electrical stability in aqueous environments while maintaining high water content (≈87%), stretchability (≈480%), and excellent biocompatibility. To illustrate the capabilities of the conductive hydrogel composites, they are applied to bionic sharks, underwater soft circuitry, and electrocardiogram electrodes. [ABSTRACT FROM AUTHOR]

Nature has a remarkable ability to create multifunctional fibers, such as spider silk, by precisely controlling structures across various scales. However, replicating this in high‐speed spun synthetic fibers is challenging due to the absence of life‐specific forces and interactions required for manipulating composition, gradients, and structures. Here, a novel droplet‐coupled pultrusion spinning technique is demonstrated for industrial‐scale production of microfibers with hierarchical structures. Droplets spontaneously form on the surface of high‐speed spun fibers to tailor multiscale hierarchical structures, resulting in a nonlinear viscoelastic core embedded with anharmonic nanosprings consisting of amorphous and crystalline domains and a periodically reinforced nanofiber skin. These structural hierarchies enable unique mechanical property combinations including nonlinear viscoelasticity, large extensibility (613%), record‐high toughness (536 MJ m−3), highly efficient impact energy absorption, vibration damping and wide temperature adaptability (−67.4 to 278.9 °C). Additionally, the structured bioinspired fibers exhibit low‐frequency phononic bandgap and anomalous dispersion of mechanical waves. The droplet‐based approach allows precise control over heterogeneity at multiple scales within the identical components leading to impressive mechanical performance and additional functionalities, and is consider that it could be applied to the design of the next era of hierarchically structured nanocomposites for a wide range of applications. [ABSTRACT FROM AUTHOR]

Wideband perfect absorbers are widely demanded for various applications, including efficient photodetection, radiation cooling. However, achieving perfect absorption across an extensive range of wavelengths on engraved structured substrate remains a challenge due to the complex light responses. It presents a hierarchical conical metasurface that demonstrates distinct perfect absorption from visible to far‐infrared range (0.4–16 µm), which is composed of surface‐engraved high aspect ratio nanogratings on microcones. The perfect absorption in the typical reststrahlen band of 4H‐SiC primarily relies on a light‐trapping‐enhanced surface phonon polaritons (SPhPs) mechanism, where the microcones effectively confine and enhance the SPhPs excited by the nanogratings through light trapping. Outside the reststrahlen band, the dominant mechanism for light antireflection is the light trapping of microcones assisted by nanogratings, which act as an equivalent antireflection layer. The hierarchical cones exhibit exceptional broadband performance, achieving an average absorptance of 98% over the spectrum of 0.4–16 µm with wide‐angle feasibility, and are fabricated using one‐step ultrafast‐laser ablation with ring‐shaped vector beams. Notably, the hierarchical cones can be applied to various materials, showing significant potential for use in photodetectors. [ABSTRACT FROM AUTHOR]

TiO2‐based materials are considered to be the promising anodes of sodium‐ion batteries (NIBs) because of their high safety and good stability. However, their low specific capacity and high safety operating voltage plateau impose a severe challenge for high energy density batteries. Herein, interconnected micro‐sheets consisting of carbon nanotubes and sulfur doped TiO2 (CNT/S‐TiO2) are synthesized via an ultrasonic process and subsequent calcination, enabling the fabrication of high‐performance material. The utilization of SWCNT overcomes the structure instabilities during electrode preparation of thick electrodes. The incorporation of SWCNT and sulfur dopants in the CNT/S‐TiO2 composite not only enhances conductivity but also improves ion transport dynamics, resulting in rapid charge delivery and high specific capacity at the thick electrode level. Consequently, CNT/S‐TiO2 demonstrates excellent rate performance (from 0.3 to 15 C, with 72.4% capacity retention) and long cycling stability (10000 cycles at a load of 1.96 mg cm−2). More importantly, the high S‐TiO2 content (90%) in the thick electrode (21.2 mg cm−2) achieves a high areal capacity retention of 3.4 mA h cm−2 after 100 cycles, which surpasses the actual application requirements. [ABSTRACT FROM AUTHOR]

Dimensional engineering of appropriate structure is an effective approach to achieve high‐performance electromagnetic (EM) wave absorption for magnetic materials. However, controllable modulation of the material configuration and a comprehensive understanding of the relationship between structure and loss mechanism remain challenging. Herein, magnetic CoNi pentagonal nanopagodas (PNPs) are ingeniously tailored using a competition orientation strategy, in which high‐density PNPs with sharp corners/edges and hierarchical structure are rooted in situ on the surface of CoNi alloy microsphere. This unique configuration of PNPs originates from the orientation growth of CoNi fivefold twins, which can be effectively regulated by manipulating metal ratio and evolves into flake‐, serrated thorn‐, prismoid‐, and blocks‐like morphologies. Optimized CoNi microspheres with high‐density PNPs exhibit a broad absorption bandwidth of 6.82 GHz at only 1.8 mm thickness. Cross‐scale magnetic coupling networks strengthen magnetic loss ability, magnetocrystalline defects induce dielectric polarization enhancement, which are intuitively confirmed by Lorentz off‐axis electron holography and geometric phase analysis. The underlying mechanism of enhanced magnetic interaction in sharp structure is clearly deciphered by micromagnetic simulation. This study provides methodological guidance for dimensional engineering in fabricating hierarchical magnetic structure and significant insights into the morphology‐dependent loss mechanism for magnetic EM absorption materials. [ABSTRACT FROM AUTHOR]

A hierarchical structure is successfully synthesized by coating polypyrrole (PPy) on the surface of carbon/saponite superlattice (denoted as PPy@C/SAP), and applied as low volume‐expansion insertion‐type anode for Li, Na, K storage.The synergistic effect of metal Ni, Fe doping, carbon/silicate superlattice, abundant oxygen vacancies and PPy coating leads to a good electronic conductivity and large current discharging capability. As a Si‐based material, PPy@C/SAP has excellent storage capability for Li (659 mAh g−1 after 1000 cycles at 2 A g−1 and 550 mAh g−1 after 1000 cycles at 5 A g−1), Na (maximum specific capacity of 533 and 327 mAh g−1 after 50 cycles) as well as K (236 mAh g−1 after 100 cycles). XPS, XANES, XRD, FTIR, HRTEM, SEM are used to detect the hybrid mechanism (bulk insertion and surface conversion) with a volume expansion as low as 9%. Insertion reaction driven by valence state change of Ni, Fe, Si (Ni0⇔Ni2+, Fe0⇔Fe3+, Si2+⇔Si4+) in laminates and conversion reactions between LiOH/Li2CO3 and LiH/Li2C2 catalyzed by Ni° contribute to the high performance. In the whole electrochemical process, layered structure is retained while the conversion reactions of LiOH (prodeced by laminates dehydroxylation) and Li2CO3 (electrolyte decomposition) cause the dynamic evolution of solid ectrolyte interphase. This study develops a promising Si‐based anode material for lithium ion batteries, sodium ion batteries and potassium ion batteries, which is significant for designing long cycle life rechargeable batteries. [ABSTRACT FROM AUTHOR]

Dielectric polarization and magnetic resonance associated with intrinsic constituent and extrinsic structure are two kinds of fundamental attenuation mechanisms for microwave absorbers, but remain extremely challenging in revealing the composition‐morphology‐performance correlation. Herein, hierarchical MXene/metal‐organic framework derivatives with coherent boundaries and magnetic units below critical grain size are constructed to realize synergistic dielectric–magnetic enhancement by phase‐evolution engineering and dynamic magnetic resonance. Specifically, phase‐evolution induced inseparable interfaces, diverse incompatible phases, and defects/vacancies contribute to dielectric polarization, while closely distributed magnetic units simultaneously realize nanoscale multi‐domain coupling and long‐range magnetic interaction. As results, the hierarchical derivatives promise an exceptional reflection loss of −59.5 dB and an effective absorption bandwidth of 6.1 GHz. Both experimental results and theoretical calculations indicate that phase‐evolution engineering and dynamic magnetic resonance maximize the absorption capability and demonstrate a versatile methodology for manipulating microwave attenuation. More importantly, the proposed multi‐domain coupling and long‐range magnetic interaction theories innovatively offer dynamic magnetic resonance mechanism for magnetic loss within critical grain size. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is an environmentally friendly biomaterial that is widely investigated because it possesses a unique hierarchical nanofiber network structure as well as extraordinary performance. In this review, the formation of the BC hierarchical nanofiber network structure from the perspective of biosynthesis is illustrated based on its basic chemical and crystal structure. Moreover, the design and processing ofBC-based advanced materials through biosynthesis, physical, and/or chemical modification are also reviewed. The intrinsic characteristics of BC, derived from its hierarchical structure, are analyzed to understand its structure-property-application relationships. The applications of advanced BC-based materials are reviewed, such as high-strength structural materials utilizing the properties of nanofibers, energy conversion and storage, bioelectronic interfaces, environmental remediation, and thermal management applications utilizing the ion transport properties and 3D network structures ofthese materials. In addition, the authors also offer their opinions and potential future research directions for sustainably developing BC-based materials. [ABSTRACT FROM AUTHOR]

Over the past decades, considerable efforts have been made to develop hierarchically porous electrodes for the high surface area, the fast velocity of fuels/products to/away from the reaction site, and the high loading of thermal‐ and/or electrochemical‐ catalysts. Manipulation of the hierarchical structure is one of the key steps for high performance in applications of efficient energy storage and conversion such as solid oxide cells. This review starts with a brief introduction to the basic concept of mass transport and how mass transport may affect performance. Then, the latest developments in enhancing the performance of cells through modification or optimization of the hierarchically porous electrode structures, including altering the geometry or morphology and increasing the triple‐phase boundaries length of electrodes are summarized. Subsequently, the unique characteristics of microstructures that are critical to enhancing electrode performance and provide important insights into the mechanisms of performance (activity and durability) enhancement, aiming at achieving the rational design of better electrode architecture are highlighted. Finally, the remaining challenges for the knowledge‐based design of highly efficient electrodes for electrochemical devices, together with possible directions and future perspectives for the development of highly efficient electrodes through optimization of microstructure are discussed. [ABSTRACT FROM AUTHOR]

The present‐day ubiquity of smart devices used under extreme conditions demands robust and more sustainable energy storage. Therefore, lightweight electrodes with both excellent electrochemical and mechanical performance to meet these needs are of great importance. Moreover, the recycling of current energy storage devices poses significant environmental concerns, a particularly daunting prospect given the increasing waste volume of metal‐based electrodes. To that end, these challenges of performance and sustainability are addressed by leveraging accessible digital light processing (DLP) technology and tailored post‐process heat treatment to fabricate a metal‐based 3D substrate with ultrahigh precision and hierarchical porosity. Here, a 4‐mm‐thickness metal‐based electrode with NiCo2S4 loading of 18.38 mg cm–2 achieves a high areal capacity of 7.327 mA h cm–2 at 44.85 mA cm–2, providing a promising way to fabricate high‐performance thick electrodes. Most importantly, these electrodes can be fabricated from recyclable metal salt feedstock. The geometric freedom offered by 3D printing supplemented by finite element analyses allows for optimized complex structures to be fabricated. Through rational design realized by 3D printing, a desirable compromise between building density, mechanical properties, electrochemical performances, and environment‐friendly processing cycle can be arrived upon. [ABSTRACT FROM AUTHOR]

High strength, toughness, and conductivity are among the most sought‐after properties of flexible electronics. However, existing engineering materials find it difficult to achieve both excellent mechanical properties and high conductivity. To address this challenge, this study proposes a facile yet versatile strategy for preparing super‐tough conductive organo‐hydrogels via freeze‐casting assisted solution substitution (FASS). This FASS strategy enables the formation of organo‐hydrogels in one step with exquisite hierarchical anisotropic structures coupled with synergistic strengthening and toughening effects across multiple length scales. As an exemplary material, the prepared polyvinyl alcohol (PVA) organo‐hydrogel with solvent content up to 87 wt% exhibits a combination of high strength (6.5 MPa), high stretchability (1710% in strain), ultra‐high toughness (58.9 MJ m−3), as well as high ionic conductivity up to 6.5 S m−1 with excellent strain sensitivity. The exceptional combination of mechanical properties and conductivity makes the PVA organo‐hydrogel a promising flexible electronics material. In addition, the FASS strategy can also endow hydrogels with multi‐functions, including thermo‐healability, freezing tolerance and shape recoverability, and can be applied to various hydrogel materials, such as carboxymethyl cellulose, sodium alginate, and chitosan. Hence, this work provides an all‐around solution for preparing advanced strong and tough conductive soft materials for a multitude of applications. [ABSTRACT FROM AUTHOR]

Aerogels are highly porous solids that maintain the properties of individual nanomaterials at a macroscopic scale. However, the inability to fabricate hierarchical architectures limits technological implementation in energy storage, gas‐sorption, or catalysis. A 3D‐printing methodology for additive‐free TiO2 nanoparticle‐based aerogels is presented with full control of the nano‐, micro‐, and macroscopic length‐scales. To compensate for ink's low solid loading of 4.0 vol% and to enable subsequent processing into aerogels via supercritical drying, the printing is done in a liquid bath of alkaline pH. The 3D‐printing protocol retains a high specific surface area of 539 m2 g–1 and a mesopore diameter of 20 nm of conventionally casted aerogels while offering an unparalleled designability on the micrometer scale. To illustrate the new geometric freedom of 3D‐printed aerogels, the microstructure of a strongly light‐absorbing, photothermal Au‐nanorod/TiO2 aerogel is defined. To date, photothermal nanomaterials are mainly applied in the form of unstructured films where scalability is limited by light attenuation. Microstructures in 3D enhance light penetration by a factor of four and facilitate spatially defined heating on a macroscopic scale. The process can be generalized for a broad material library and allows to design inks with specific functionality, thus making aerogels adaptable for their target application. [ABSTRACT FROM AUTHOR]

The ice templating assembly has been investigated to construct macroporous channels of functional nanomaterials with well‐defined homogeneous morphology. Recently, this templating method has been revisited integrating with other materials' synthesis and processing methodologies (such as, spinning, spraying, filtration, hydrothermal, oxygenation, gelation, and 3D printing) for electrochemical energy conversion and storage applications. Herein, the recent progress on "integrative ice frozen assembly" focusing on the hierarchical structures and chemistries of functional nanomaterials such as, organic, inorganic, carbon, and composite materials for a rational design of energy application‐oriented materials is comprehensively reviewed. This integrative process allows functional nanomaterials to be assembled into various dimensions, such as, 0D, 1D, 2D, and 3D macrostructures, as well as, into larger bulk objects such as, fibers, films, monoliths, and powders. The fundamental understanding of the integrative ice frozen assembly is thermodynamically and kinetically discussed with the help of primitive freeze casting domain knowledge and the energy conversion and storage performances of the as‐designed electrodes with their hierarchical structures and chemistries are further correlated. The applications of the as‐assembled electrodes into batteries, supercapacitors, fuel cells, and electrocatalysis are also addressed. Finally, the perspective on the current impediments and future directions in this field is discussed. [ABSTRACT FROM AUTHOR]

Solar‐powered water evaporation is a straightforward, practical approach to use solar energy for water desalination. Solar absorbers made from photothermal materials capable of effectively confining heat and pumping water to the evaporation surface are essential for a high energy efficiency. However, separate designs of water transport routes and thermal insulating layers are required to simultaneously achieve desired water and thermal managements. This work reports an integrated design for efficient multifunctional capabilities through rational assembly of spectrally modified Ti3C2Tx (SM‐Ti3C2Tx) nanosheets and polyvinyl alcohol (PVA) into a multiscale 3D aerogel with a feather‐like microstructure. The aerogel contains longitudinal struts with transversely parallel ligaments developed at an angle of ≈60° from the struts, resembling the microstructure of down feathers in penguins and thus leading to excellent thermal insulation. The hydrophilic porous ligaments serve as upward water transport channels, pumping the water to the evaporation surface while confining it within the ligaments to avoid oversaturation. These functional features endow the composite aerogel with a high energy efficiency of 88.52% and an evaporation rate of 0.92 kg m−2 h−1 at a weak solar irradiance of 0.5‐sun, indicating its great potential for practical solar‐powered water desalination under natural sunlight. [ABSTRACT FROM AUTHOR]

Shape‐morphing active networks of mesoscale filaments are a common hierarchical feature in biology for applying forces, transporting materials, and inducing motility with microscale resolution. Synthetic morphing systems of similar dimensions and capabilities hold potential for a range of technological applications, from micro‐muscles to shape‐morphing optical devices. Here, the fabrication of highly‐ordered 2D networks hierarchically constructed of thermoresponsive mesoscale polymeric fibers, which can exhibit morphing with microscale resolution, is presented. It is demonstrated both experimentally and computationally that the morphing of such networks strongly depends on the physical attributes of the single fiber, in particular on two intrinsic length scales—the fiber diameter and mesh size, which stems from network's density. It is shown that depending on these parameters, such fiber‐networks exhibit one of two thermally driven morphing behaviors: i) the fibers stay straight, and the network preserves its ordered morphology, exhibiting a bulk‐like behavior; or ii) the fibers buckle and the network becomes messy and highly disordered. Notably, in both cases, the networks display memory and regain their original ordered morphology upon shrinking. This hierarchically induced phase transition, demonstrated here on a range of networks, offers a new way of controlling the shape‐morphing of synthetic materials with mesoscale resolutions. [ABSTRACT FROM AUTHOR]

Red phosphorus (RP), with high theoretical specific capacity and low working potential, has been regarded as one of the most promising anodes for high‐performance sodium‐ion batteries (SIBs). However, the unsatisfactory performance of RP anodes especially under high mass loading conditions severely limited the development for practical applications, due to its large volume variations during cycling processes, and the poor electronic and ionic conductivity. Here, a hierarchical WDC/CNTs@RP electrode with high mass loadings of RP (up to 14.1 mg cm−2) and superior conductivity is rationally designed for both ions and electrons. Such unique hierarchical structures enable an unprecedented rate performance (1.63 mAh cm−2 under 106.6 mA cm−2), long cycling life, and a decent gravimetric capacity of 468.88 mA h g−1 based on the whole electrode and inactive components. This work presents an essential step toward practical applications of RP anode materials for SIBs batteries. [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]

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]

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]

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]

The high incidence of postoperative recurrence and metastasis has a serious effect on survival in breast cancer patients. Moreover, it is still a great challenge to prevent the postoperative recurrence and metastasis through traditional implantable devices due to their inability to control multiple drug release. Herein, an implantable hierarchical structured ultrafine fiber device with a time‐programmed drug release function for the local postoperative adjuvant chemotherapy of breast cancer is developed. The structure is obtained through a co‐axial electrospinning technology by the formation of the periodically arranged chambers inside a fiber matrix. The Doxorubicin hydrochloride in these chambers is released rapidly, killing the residual tumor cells to prevent tumor recurrence; while the matrix metalloproteinases‐2 (MMP‐2) inhibitor disulfiram in the fiber matrix is released in a sustained manner, inhibiting tumor invasion to prevent its metastasis. The fiber device implanted in tumor‐bearing mice after a surgical tumor reduction displays excellent therapeutic efficacy by preventing both recurrence and metastasis. The mechanism investigation of tumor invasion through the type‐II collagen immunofluorescence analysis reveals that the decrease of the activity of MMP‐2 plays a key role in this process. [ABSTRACT FROM AUTHOR]

Microcosmic 3D hierarchical structural design has proved to be an effective strategy to obtain high‐performance microwave absorbers, although the treatments to low‐dimensional cells in monolithic framework are usually based on semiempirical rules. In this work, a hierarchical carbon fiber (CF)@MXene@MoS2 (CMM) core‐sheath synergistic structure with tunable and efficient microwave absorption (MA) properties is fabricated by introducing self‐assembled Ti3C2Tx MXene on the surface of CF and subsequent anchoring of MoS2. By the synergistic effects from the MXene sheath increasing the conductive loss and MoS2 at the outermost layer improving the impedance matching, the MA performance of CMM can be effectively regulated and optimized: the optimal reflection loss is −61.51 dB with a thickness of 3.5 mm and the maximum effective absorption bandwidth covers the whole Ku‐band with 7.6 GHz at 2.1 mm. Meanwhile, the whole X‐band absorption can also be achieved with specific MoS2 loading at an optimized thickness. [ABSTRACT FROM AUTHOR]

Mechanical properties of hydrogels can be modified by the variation of structure and concentration of reactive building blocks. One promising biological source for the synthesis of biocompatible hydrogels is fibrinogen. Fibrinogen is a glycoprotein in blood, which can be transformed enzymatically to fibrin playing an important role in wound healing and clot formation. In the present work, it is demonstrated that hybrid hydrogels with their improved mechanical properties, tunable internal structure, and enhanced resistance to degradation can be synthesized by a combination of fibrinogen and reactive amphiphilic copolymers. Water‐soluble amphiphilic copolymers with tunable molecular weight and controlled amounts of reactive epoxy side groups are used as reactive crosslinkers to reinforce fibrin hydrogels. In the present work, copolymers that can influence the mechanical properties of fibrin‐based hydrogels are used. The reactive copolymers increase the storage modulus of the hydrogels from 600 Pa to 30 kPa. The thickness of fibrin fibers is regulated by the copolymer concentration. It could be demonstrated that the fibrin‐based hydrogels are biocompatible and support cell proliferation. Their degradation rate is considerably slower than that of native fibrin gels. In conclusion, fibrin‐based hydrogels with tunable elasticity and fiber thickness useful to direct cell responses like proliferation and differentiation are produced. [ABSTRACT FROM AUTHOR]

Graphene‐based aerogels have been widely studied for their high porosity, good compressibility, and electrical conductivity as piezoresistive sensors. However, the fabrication of graphene aerogel sensors with good mechanical properties and excellent sensing properties simultaneously remains a challenge. Therefore, in this study, a novel nanofiber reinforced graphene aerogel (aPANF/GA) which has a 3D interconnected hierarchical microstructure with surface‐treated PAN nanofiber as a support scaffold throughout the entire graphene network is designed. This 3D interconnected microporous aPANF/GA aerogel combines an excellent compressive stress of 43.50 kPa and a high piezoresistive sensitivity of 28.62 kPa−1 as well as a wide range (0–14 kPa) linear sensitivity. When aPANF/GA is used as a piezoresistive sensor, the compression resilience is excellent, the response time is fast at about 37 ms at 3 Pa, and the structural stability and sensing durability are good after 2600 cycles. Indeed, the current signal value is 91.57% of the initial signal value at 20% compressive strain. Furthermore, the assembled sensors can monitor the real time movement of throat, wrist pulse, fingers, wrist, and knee joints of the human body at good sensitivity. These excellent features enable potential applications in health detection. [ABSTRACT FROM AUTHOR]

Bottom‐up assembly can organize simple building blocks into complex architectures for light manipulation. The optical properties of self‐assembled polycrystalline barium carbonate/silica double helices are studied using fluorescent Fourier and Mueller matrix microscopy. Helices doped with fluorescein direct light emission along the long axis of the structure. Furthermore, light transmission measured normal and parallel to the long axis exhibits twist sense‐specific circular retardance and waveguiding, respectively, although the measurements suffer from depolarization. The helices thus integrate highly directional emission with enantiomorph‐specific polarization. This optical response emerges from the arrangement of nanoscopic mineral crystallites in the microscopic helix, and demonstrates how bottom‐up assembly can achieve ordering across multiple length scales to form complex functional materials. [ABSTRACT FROM AUTHOR]

Spider silk fibers (SSF) have a hierarchical structure composed of proteins with highly repetitive sequences and biomineralization is sophisticated in hierarchical organic–inorganic constructions. By using inorganic hydroxyapatite (HAP) and organic polyvinyl alcohol (PVA) to simulate the rigid crystalline and flexible amorphous protein blocks of SSF, respectively, biomimetic mineralization is herein attempted for the large‐scale preparation of SSF‐like macrofibers with a hierarchical ordered structure, a superhigh tensile strength of 949 ± 38 MPa, a specific toughness of 296 ± 12 J g−1, and a stretch ability of 80.6%. The hybrid macrofibers consist of microfibers, and their outstanding performance (e.g., extreme tolerance to temperatures ranging from −196 to 80 °C and superior ability to inhibit the transverse growth of cracks) is attributed to the hierarchical arrangement as well as the organic–inorganic integrated structure within the oriented mineralized polymer chains. The biomineralization‐inspired technique provides a promising tactic that can be used to synthesize functional organic–inorganic fibers that are structurally complex and, furthermore, industrially manufacture SSF‐like artificial fibers with a supertoughness. [ABSTRACT FROM AUTHOR]

Reinforced polymer‐based composites are attractive lightweight materials for aircrafts, automobiles, and turbine blades, but still show strength and fracture toughness lower than traditional metals. An interesting approach to address this issue is to fabricate composites with structural features that absorb part of the elastic energy stored in the material during fracture through extrinsic and intrinsic toughening mechanisms behind and ahead of the crack tip, respectively. Inspired by the nacreous layer of mollusk shells, the fracture behavior of multiscale composites that combine intrinsic toughness from a brick‐and‐mortar structure connected through nanoscale mineral bridges and extrinsic toughness arising from a brittle–ductile laminate architecture at the millimeter scale are fabricated and investigated. Such a hierarchical toughening approach increases the dissipated energy by more than 30‐fold during fracture with minimal loss in stiffness and strength. Using simple energy balance arguments and fracture mechanics concepts, guidelines are established for the design of nacre‐like composites with a remarkable combination of stiffness, strength, and toughness. This demonstrates the possibility to controllably introduce toughening mechanisms at different length scales and to thus fabricate hierarchical composites with high fracture resistance in spite of the brittle nature of their main inorganic constituents.The design principles of tough biological materials are investigated by studying nacre‐inspired composites structured across three length scales. The organic layers between nacre layers are conceptually mimicked using polymer films in between synthetic nacre. These hierarchical materials exhibit high mechanical properties and offer new insights into the multiscale toughening mechanisms responsible for the outstanding fracture resistance of mollusk shells. [ABSTRACT FROM AUTHOR]

Abstract: A facile approach to the fabrication of bioinspired hierarchical functional structures by using honeycomb films with controllable micropores as templates is described here. Taking advantage of the breath figure method, honeycomb films with manipulable micropores can be conveniently fabricated by modulating the experimental conditions such as duration of the moist gas flow, temperature, and stretching of the film, which further serve as templates to induce the assembly of subsequently introduced silica nanoparticles for the construction of hierarchical functional structures in a controlled fashion. The resultant hierarchical functional structures not only present a viewing angle independent property, but also exhibit improved hydrophobicity and unique wetting behaviors depending on the morphologies of their building units. It is believed that the work will provide plenty of inspiration for the fabrication of novel high‐performance optical devices for display, as well as functionalized surfaces for waterproof and self‐cleaning. [ABSTRACT FROM AUTHOR]

Abstract: Despite their high theoretical specific capacity (1675 mA h g−1), the practical application of Li–S batteries remains limited because the capacity rapidly degrades through severe dissolution of lithium polysulfide and the rate capability is low because of the low electronic conductivity of sulfur. This paper describes novel hierarchical yolk–shell microspheres comprising 1D bamboo‐like N‐doped carbon nanotubes (CNTs) encapsulating Co nanoparticles (Co@BNCNTs YS microspheres) as efficient cathode hosts for Li–S batteries. The microspheres are produced via a two‐step process that involves generation of the microsphere followed by N‐doped CNTs growth. The hierarchical yolk–shell structure enables efficient sulfur loading and mitigates the dissolution of lithium polysulfides, and metallic Co and N doping improves the chemical affinity of the microspheres with sulfur species. Accordingly, a Co@BNCNTs YS microsphere‐based cathode containing 64 wt% sulfur exhibits a high discharge capacity of 700.2 mA h g−1 after 400 cycles at a current density of 1 C (based on the mass of sulfur); this corresponds to a good capacity retention of 76% and capacity fading rate of 0.06% per cycle with an excellent rate performance (752 mA h g−1 at 2.0 C) when applied as cathode hosts for Li–S batteries. [ABSTRACT FROM AUTHOR]

Abstract: Molecular assembly offers a bottom‐up way to construct biomimetic architectures with unique structures and properties. Although artificial photophosphorylation systems have long been developed, their microstructures have yet to achieve the sophisticated order and hierarchy of natural organisms. Herein, by utilizing principles in the natural plant leaves, it is shown that a biomimetic system with hierarchically ordered and compartmentalized structures, combining photosystem II (PSII) and adenosine triphosphate (ATP) synthase, can be obtained through template‐directed layer‐by‐layer assembly. Under light illumination, PSII in such a highly ordered light‐harvesting array, splits water to produce protons and electrons. Furthermore, a remarkable proton gradient is created across the covering ATP synthase‐reconstituted lipid membrane. As a consequence, highly efficient photophosphorylation is achieved. Outstandingly, the rate of ATP production in this hierarchical light‐harvesting architecture is enhanced 14 times, compared to that in the nature. This study paves a new way to assemble bioinspired systems with enhanced solar‐to‐chemical energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Bioinspired materials design aims for high‐performing composite materials based on natural biomineralization processes and biomineral architectures. A key component to the research is the bioorganic–inorganic interface, one of the most crucial parameters for controlling the material properties. In this study, genetically engineered phages expressing an inorganic‐binding peptide for the molecular recognition of a ceramic material is exploited to generate thin film multilayer assemblies, with the phage template as minority component. The bioorganic–inorganic interface in the ceramic (zinc oxide, ZnO) multilayer systems is strengthened by the ZnO‐binding motif HSSHH of a peptide to increase Young's modulus and hardness. Applying a point‐mutated version of the peptide, DSSHH, which modulates the interface forces, shows an increased fracture toughness without deteriorating the Young's modulus and the hardness. Molecular matching of the organic phase and its modulation in order to form a specific interface is shown to be important in controlling material properties like in natural biominerals. With this tool in hand, it is not only possible to imitate the structure of biominerals but also to genetically control the molecular recognition of bioorganic molecules to induce macroscopic effects in synthetic composite materials. [ABSTRACT FROM AUTHOR]

Abstract: The fabrication of stimulus‐responsive coatings that change both reflectivity and topography is hampered by the lack of easy processable, patternable, and programmable elastomers. Here, an easily applied reflective coating based on a semi‐interpenetrating polymer network composed of a liquid crystal elastomer and a liquid crystal network (>15 wt%) is reported. The reflective wavelength of these polysiloxane elastomer photonic coatings can be readily programed by the concentration of chiral reactive mesogen dopant that forms the network. The coatings show a fast and reversible decrease in reflection band intensity with increasing temperature, which can be tuned by the polymer network density. In addition, hierarchical surface relief structures are prepared, which can be reversibly changed with temperature. [ABSTRACT FROM AUTHOR]

Abstract: In energy storage materials, large surface areas and oriented structures are key architecture design features for improving performance through enhanced electrolyte access and efficient electron conduction pathways. Layered hydroxides provide a tunable materials platform with opportunities for achieving such nanostructures via bottom‐up syntheses. These nanostructures, however, can degrade in the presence of the alkaline electrolytes required for their redox‐based energy storage. A layered Co(OH)2–organic hybrid material that forms a hierarchical structure consisting of micrometer‐long, 30 nm diameter tubes with concentric curved layers of Co(OH)2 and 1‐pyrenebutyric acid is reported. The nanotubular structure offers high surface area as well as macroscopic orientation perpendicular to the substrate for efficient electron transfer. Using a comparison with flat films of the same composition, it is demonstrated that the superior performance of the nanotubular films is the result of a large accessible surface area for redox activity. It is found that the organic molecules used to template nanotubular growth also impart stability to the hybrid when present in the alkaline environments necessary for redox function. [ABSTRACT FROM AUTHOR]

Materials with highly ordered molecular arrangements have the capacity to display unique properties derived from their nanoscale structure. Here, the synthesis and characterization of azobenzene (AZO)-functionalized siloxane oligomers of discrete length that form photoswitchable supramolecular materials are described. Specifically, synergy between phase segregation and azobenzene crystallization leads to the self-assembly of an exfoliated 2D crystal that becomes isotropic upon photoisomerization with UV light. Consequently, the material undergoes a rapid athermal solid-to-liquid transition which can be reversed using blue light due to the unexpectedly fast 2D crystallization that is facilitated by phase segregation. In contrast, enabling telechelic supramolecular polymerization through hydrogen bonding inhibits azobenzene crystallization, and nanostructured pastes with well-ordered morphologies are obtained based on phase segregation alone, thus demonstrating block copolymer-like behavior. Therefore, by tailoring the balance of self-assembly forces in the azobenzene-functionalized siloxane oligomers, fast and reversible phase-changing materials can be engineered with various mechanical properties for applications in photolithography or switchable adhesion to lubricant properties. [ABSTRACT FROM AUTHOR]

Developing novel filtering materials with both high permeation flux and rejection rate presents an enticing prospect for oil/water separation. In this paper, robust porous poly(melamine formaldehyde) (PMF) sponges with superwettability and controlled pore sizes through introducing layered double hydroxides (LDH) and SiO2 electrospun nanofibers are reported. The LDH nanoscrolls endow the sponge with inherent superhydrophilicity and the SiO2 nanofibers act as pore size regulators by overlapping the PMF mainframe. This approach allows the intrinsic large pores in the pristine sponge to decrease quickly from 109.50 to 23.35 µm, while maintaining porosity above 97.8%. The resulting modified sponges with varied pore sizes can effectively separate a wide range of oil/water mixtures, including the surfactant-stabilized emulsions, solely by gravity, with ultrahigh permeation flux (maximum of 3 × 105 L m−2 h−1 bar−1) and satisfactory oil rejection (above 99.46%). Moreover, separation of emulsions stabilized by different surfactants, such as anionic, nonionic, and cationic surfactants has been investigated for further practical evaluation. It is expected that such a pore size tuning technology can provide a low cost and easily scaled-up method to construct a series of filtering materials for high-efficient separation of target oil/water mixtures. [ABSTRACT FROM AUTHOR]

Nanoparticle assembly and colloidal processing are two techniques with the goal to fabricate materials and devices from preformed particles. While colloidal processing has become an integral part of ceramic processing, nanoparticle assembly is still mainly limited to academic interests. It typically starts with the precise synthesis of building blocks, which are generally not only considerably smaller than those used for colloidal processing, but also better defined in terms of size, shape, and size distribution. Their arrangement into 1D, 2D, and 3D architectures is performed with great accuracy well beyond what is achieved by colloidal processing. At the same time, the final assembly is not sintered such that the intrinsic, nanospecific properties of the initial building blocks are preserved or even lead to collective behavior. However, in contrast to colloidal processing the structures accessible by nanoparticle assembly are often limited to a small length scale. The review presents selected examples of nanoparticle assembly and colloidal processing with the goal to reveal the capabilities of these two techniques to fabricate novel materials from preformed building blocks, and also to demonstrate the immense opportunities that would arise if the two methods could be combined with each other. [ABSTRACT FROM AUTHOR]

Discovering new methods to tailor the physical and chemical properties of metal-organic frameworks (MOFs) for their numerous potential applications is highly desired. In this work, engineering defects in MOF via a molecular imprinting approach is developed to endow HKUST-1, a well-studied classical MOF, with hierarchical structure, mesoporosity, and anionic framework property. Ringlike anionic HKUST-1 (HKUST-1-R) and a wide variety of metal-doped isostructural analogues ( M/HKUST-1-R, M = Ca, Cd, Ce, Co, Li, Mn, Na, Ni, or Zn) are obtained. The benefits of transforming imprinted HKUST-1-R to M/HKUST-1-R are further demonstrated for various applications. This synthetic strategy is therefore suitable for rational design and functionalization of MOFs in addition to their morphological control in nanoscale. [ABSTRACT FROM AUTHOR]

Nanofabrication is an indispensable process in nanoscience and nanotechnology. Unconventional lithographic techniques are often used for fabrication as alternatives to photolithography because they are faster, more cost-effective, and simpler to use. However, these techniques are limited in scalability and utility because of the collapse of preprinted structures during step-and-repeat processes. This study proposes a new class of temperature-controllable polymeric molds that are coated with a metal such that any site-specific patterning can be accomplished in a programmable manner using selective contact-dewetting lithography. The lithography allows sub-100 nm patterning, step-and-repeat processing, and hierarchical structure fabrication. The programmable feature of the lithography can be utilized for the structural coloring and shaping of objects. Large-area programmable patterning, semiconductor device manufacturing, and the fabrication of iridescent security devices would benefit from the unique features of the proposed strategy. [ABSTRACT FROM AUTHOR]

In biomedical applications, it is very desirable to monitor the in vivo state of implanted devices, i.e., tracking the location, the state, and the interaction between the implanted devices and cell tissues. To achieve this goal, a generic strategy of soft materials meso-functionalization is presented. This is to acquire silk fibroin (SF) materials with added functions, i.e., in vivo bioimaging/sensing. The functionalization is by 3D materials assembly of functional components, lanthanide(Ln)-doped upconversion nanoparticles (UCNPs) on the mesoscopic scale to acquire upconversion fluorescent emission. To implement the meso-functionalization, the surfaces of UCNPs are modified by the hydroxyl groups (OH) from SiO2 or polyethylene glycol coating layers, which can interact with the carbonyl groups (CO) in SF scaffolds. The functionalized silk scaffolds are further implanted subcutaneously into mice, which allows the silk scaffolds to have fluorescent in vivo bioimaging and other biomedical functions. This material functionalization strategy may lead to the rational design of biomaterials in a more generic way. [ABSTRACT FROM AUTHOR]

The rational design of high-performance flexible pressure sensors attracts attention because of the potential applications in wearable electronics and human-machine interfacing. For practical applications, pressure sensors with high sensitivity and low detection limit are desired. Here, ta simple process to fabricate high-performance pressure sensors based on biomimetic hierarchical structures and highly conductive active membranes is presented. Aligned carbon nanotubes/graphene (ACNT/G) is used as the active material and microstructured polydimethylsiloxane (m-PDMS) molded from natural leaves is used as the flexible matrix. The highly conductive ACNT/G films with unique coalescent structures, which are directly grown using chemical vapor deposition, can be conformably coated on the m-PDMS films with hierarchical protuberances. Flexible ACNT/G pressure sensors are then constructed by putting two ACNT/G/PDMS films face to face with the orientation of the ACNTs in the two films perpendicular to each other. Due to the unique hierarchical structures of both the ACNT/G and m-PDMS films, the obtained pressure sensors demonstrate high sensitivity (19.8 kPa−1, <0.3 kPa), low detection limit (0.6 Pa), fast response time (<16.7 ms), low operating voltage (0.03 V), and excellent stability for more than 35 000 loading-unloading cycles, thus promising potential applications in wearable electronics. [ABSTRACT FROM AUTHOR]

The utilization of porous carbon frameworks as hosts for sulfur loading is an important theme in current Li-S battery research. Unfortunately, the high loading of insulating sulfur often leads to low specific capacities, poor rate properties, and rapid capacity loss. To address this challenge, a facile templating route to fabricate a novel host material, hierarchical porous carbon rods constructed by vertically oriented porous graphene-like nanosheets (HPCR) is presented. With a high specific surface area, ultralarge pore volume, hierarchical porous structures, and ideal ion transfer pathways, HPCR is a promising candidate for high sulfur loading. When used as the active material for a sulfur cathode, the HPCR-S composite with 78.9 wt% sulfur exhibits excellent rate performance (646 mAh g−1sulfur at 5 C) and cycling stability (700 mAh g−1sulfur after 300 cycles at 1 C). Even with a sulfur content of 88.8 wt%, the HPCR-S composite, without any additional protective polymer coating, still delivers a good rate performance (545 mAh g−1sulfur at 3 C) and cycling stability (632 mAh g−1sulfur after 200 cycles at 1 C). More importantly, the high sulfur loading (88.8 wt%) ensures that the HPCR-S composite has a high energy density (880 mAh cm−3cathode after 200 cycles at 1 C). [ABSTRACT FROM AUTHOR]

Silk fibers spun by silkworms or spiders at ambient temperature display unique mechanical strength, excellent biocompatibility and optical transparency, which offer unconventional interfaces to soft and curved biological systems. In comparison with conventional materials, the performance of soft matter, i.e., animal silks, is mainly determined by the structure at the mesoscale. To further extend the applications, functionalization of silk materials becomes is required, and mesoscopic material assembly (MMA) was developed for this task. This feature article provides an overview on the principles and strategies concerning MMA, and some typical examples of functionalizing silk fibroin materials. The main strategies of MMA include in vivo and in vitro assemblies, and can be implemented by the three different paths: (1) molecular recognition, (2) surface functionalization of nanomaterials, or (3) foreign molecule mediation. The cases include the functionalization of silk fibroin materials by one/two-photon fluorescent molecules, quantum dots (QDs) and gold clusters, etc. The applications of these functionalized materials in bio waveguide, white-light-emitting devices, bioimaging, were also highlighted. MMA provides a practical tool for the production of the functionalized biocompatible materials, which can be further applied to fabricate high-performance bio integrated devices used in consumer electronics, and biomedical diagnosis, as well as human-machine interfaces. [ABSTRACT FROM AUTHOR]

Metal organic framework (MOF)-derived nitrogen-enriched nanocarbons have been proposed as promising metal-free electrocatalysts for oxygen reduction reaction. However, the characteristic microporous feature of MOF-derived carbon determined by the MOF structure significantly hinders the mass transfer and exposure of active sites, resulting in unsatisfactory electrocatalytic performance. Here an in situ confinement pyrolysis strategy that can simply but efficiently transform monodisperse ZIF-8 polyhedrons to nitrogen-enriched meso-microporous carbon (NEMC) frameworks is reported. Using this strategy, 3D NEMC frameworks, 1D NEMC fibers, and 2D NEMC on graphene (NEMC/G) can be successfully obtained. As a metal-free elctrocatalyst, optimized NEMC/G can reach a comparable electrocatalytic activity with superior stability and methanol resistance to commercial 30 wt% Pt/C catalyst in 0.1 m KOH solution. Such enhanced performance can be ascribed to the stable and highly open network consisting of NEMC and G with fully exposed active sites, thereby leading to durable catalytic activity. [ABSTRACT FROM AUTHOR]