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Hypothesis One prevailing method to construct excellent temperature tolerance/long-lasting moisture hydrogels is to couple the original hydrogel networks with freezing-tolerant/moisture retaining agents, including ionic liquids, inorganic salts, zwitterionic osmolytes, and polyhydric alcohols. Among them, organohydrogels have shed new light on the development of ionic skins with long-term usability and stable sensing performance at subzero temperatures due to their long-lasting water retention and anti-freezing capability. Experiments We report a dual network organohydrogel by doping conductive ZnSO4 into the double network hydrogel of polyvinyl alcohol-polyacrylamide (PVA-PAM) with subsequent immersing in a mixed solvent of ethylene glycol (EG) and H2O. The anti-freezing and moisture retaining abilities of the PVA/PAM/Zn/EG (PPZE) organohydrogel were studied and the sensing performances of the PPZE organohydrogel-based ionic skin were investigated. Findings The organohydrogel exhibits a high conductivity (0.44 S m−1), excellent fatigue resistance and exceptional moisture retaining ability with more than 99.3% of the initial weight retention after 31 days storage at ambient temperature. Importantly, the PPZE organohydrogel-based ionic skin shows an ultra-low temperature anti-freezing ability and remains flexibility and sensing capability with a high sensitivity (signal response time ∼ 0.23 s) even at -50 °C. The PPZE organohydrogel demonstrates a tremendous potential in artificial skin and health monitoring.

Summary The photomagnetic effect is known to be related only to transition metal atoms with empty orbitals and spin-state changes. In general, noble metals with high electron density cannot be used as photomagnetic materials because of the absence of spin polarization. However, here, we found that photomagnetic-chiral anisotropy (PM-ChA) was generated in chiral nanostructured Au films (CNAFs), and opposite photomagnetic fields (PMFs) were created in the antipodal CNAFs under unpolarized irradiation. The PM-ChA was speculated to arise from directional alignment of opposite spins polarized by the asymmetric spin-orbit coupling due to the opposite effective magnetic fields induced by electron motion in the antipodal helical structure. PM-ChA can be applied in enantiomeric quantification, probably because of the spin polarization coupling between CNAFs and enantiomers. PM-ChA of noble metals generated by directional spin control in helical nanostructures could provide new strategies in quantum technology and theories in magnetophysics.

Recently, Coordination Polymers (CPs) have been widely utilized as energy storage materials for reversible Lithium-Ion Batteries (LIBs) benefiting from their tunable building blocks and adjusted electrochemical properties. However, the unsatisfied electrochemical behavior of CPs with poor conductivity and sluggish ion transport kinetics is still a bottle-neck for their large-scale energy storage applications in LIBs. Herein, we display the rational fabrication of a conductive Sn-based coordination polymer (Sn-DHTPA) via judiciously choosing suitable building units. The Sn-DHTPA is employed as anode for LIBs, exhibiting superior reversible storage capacity of 1142.6 mA h g−1 at 0.1 A g−1 after 100 cycles and impressive rate storage capability of 287.7 mA h g−1 at 20 A g−1. More importantly, a robust cycling performance of 205.5 mA h g−1 at an extra-high current density of 20 A g−1 are observed without remarkable capacity-fading up to 1000 cycles. The behavior superiority of Sn-DHTPA is related to its advanced architecture with abundant lithium storage sites, high electrical conductivity and rapid lithium transport. A series of ex-situ characterizations reveal that the impressive lithium storage capacity is contributed by the redox active sites of both the aromatic linker and metal center related to in-situ generated metallic nanoparticles dispersed in the skeleton.

Rational construction of hybrid materials integrating the collective virtues of individual building blocks has spurred significant interest in electrode materials for energy storage. Herein, a smart hybrid was fabricated via in-situ assembling of the few-layered MoS2 (f-MoS2) coated on the multi-layered Ti3C2 MXene decorated with the TiO2 nanoparticles by the scalable hydrothermal and annealing approaches. In the unique architecture, the multi-layered Ti3C2 with the expanded interspaces as the conductive backbone can facilitate the electron transport, provide adequate space to facilitate the infiltration of organic electrolyte into the interior of electrode, and inhibit the aggregation of MoS2 nanosheets, while the f-MoS2 with enlarged interlayer can be beneficial for the lithium-ion diffusion and prevent the multi-layered Ti3C2from restacking. Moreover, the TiO2 decorated on the Ti3C2 can effectively inhibit the instability of long-chain lithium polysulfides dissolved in organic electrolyte to improve the cycling stability. Thanks to the synergistic effect of the building blocks, the Ti3C2/TiO2@f-MoS2 hybrid employed as lithium storage anode delivers an extraordinary endurable ability with a high storage capacity of 403.1 mA h g−1 after 1200 cycles at 2 A g−1. Importantly, the smart hybridization strategy in this work paves an efficient way to explore the high-performance MXene-based hybrid materials in energy storage fields.

Platinum (Pt) is the most effective bench-marked catalyst for producing renewable and clean hydrogen energy by electrochemical water splitting. There is demand for high HER catalytic activity to achieve efficient utilization and minimize the loading of Pt in catalysts. In this work, we significantly boost the HER mass activity of Pt nanoparticles in Pt x /Co to 8.3 times higher than that of commercial Pt/C by using Co/NC heterojunctions as a heterogeneous version of electron donors. The highly coupled interfaces between Co/NC and Pt metal enrich the electron density of Pt nanoparticles to facilitate the adsorption of H + , the dissociation of Pt-H bonds and H 2 release, giving the lowest HER overpotential of 6.9 mV vs. RHE at 10 mA/cm 2 in acid among reported HER electrocatalysts. Given the easy scale-up synthesis due to the stabilization of ultrafine Pt nanoparticles by Co/NC solid ligands, Pt x /Co can even be a promising substitute for commercial Pt/C for practical applications.

W/CuCrZr alloy composite panels are promising plasma-facing components for use in future nuclear-fusion reactors. However, the intrinsic immiscibility of W and Cu makes joining them difficult. In this study, we developed a vacuum diffusion bonding method that involves sandblasting of the W substrate surface, Cu electroplating and annealing, and subsequent vacuum diffusion bonding to realize W/CuCrZr joints with high bond strength. The morphologies and structures of the W and W/CuCrZr joints were investigated by scanning electron microscopy, X-ray diffraction, and high-resolution transmission electron microscopy. Sandblasting was found to induce the plastic deformation, roughening, and grain refinement of the W substrate surface. During Cu plating on the surface of the sandblasted W (and subsequent annealing), the Cu layer was embedded in micron-scale irregular pits on the sandblasted W surface, creating a tight bond. The shear bond strength (184 MPa) and bonding quality of a W/CuCrZr joint obtained with the sandblasting/Cu interlayer method was superior to those of a W/CuCrZr joint prepared by conventional vacuum diffusion bonding. The structural origins of this superior W/CuCrZr joint were related to a region of W and Cu interdiffusion with a thickness of approximately 30 nm. This improved vacuum diffusion bonding method for W and CuCrZr can facilitate the development of plasma-facing components for future nuclear-fusion devices.

Oxide-dispersion-strengthened tungsten (ODS-W) and a CuCrZr alloy were bonded by a three-step process: (i) surface nano-activation, (ii) copper plating followed by annealing, and (iii) diffusion bonding. The morphological and structural evolutions of ODS-W and the interface of the ODS-W/CuCrZr joint during these processes have been thoroughly studied by X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry, and high-resolution transmission electron microscopy. After surface nano-activation, a nanoporous structure of ODS-W with an average pore size of ~100 nm was obtained, and the Y2O3 particles therein remained unchanged. A Cu coating was tightly bonded with the surface nano-activated ODS-W after Cu plating and annealing. An interaction layer embedded with nanosized W particles was formed at the interface between ODS-W and plated Cu after the three-step process. Consequently, well-cohesive ODS-W/Cu and ODS-W/Y2O3/Cu interfaces were formed. The ODS-W/CuCrZr joint showed high shear strengths (up to 201 MPa) and effective bonded area ratios (>98%). The developed three-step bonding process between ODS-W and the CuCrZr alloy provides an effective support for future plasma-facing components in nuclear fusion reactor applications.

Semiconductor-metal heterostructure, especially represented by various inorganic semiconductors-platinum (Pt) hybrids, is widely applied in converting solar power to chemical energy. Given the scarcity of Pt and the availability of coupling, the development of a non-Pt regimen and facile assembly strategy is critical. In this study, CdxZn1-xS/Ti3C2 ultrathin MXene composites were availably prepared with a facile electrostatic assembly strategy. The unique 0D/2D assembly demonstrated remarkably enhanced performance toward photocatalytic hydrogen production compared with bare CdxZn1-xS. Spectroscopic characterization analysis and band theory discussion substantiated the effects of electronic interaction and the Schottky barrier arising from intimate contact of CdxZn1-xS and Ti3C2 MXene on the swift separation of photoinduced electron-hole pairs. Successful application of electrostatic self-assembled CdxZn1-xS with ultrathin MXene opens a new area of utilizing electrical difference and band theory to prepare rational semiconductor/MXene Schottky structure towards various photocatalytic reactions.

Zinc-based energy storage systems (zinc-air, zinc-nickel and zinc-ion batteries and zinc-ion hybrid supercapacitors (ZHSs) are considered as promising power sources for wide applications from personal electronic devices to electric vehicles. However, these systems, especially the Zn-based hybrid supercapacitors, display unsatisfying power density and energy density, which should be enhanced for their large-scale applications. In this work, aqueous alkaline zinc-carbon hybrid supercapacitors (A-ZCHS) were designed, consisting of B, N dual doped carbon cathode, Zn anode and KOH electrolyte. The B, N dual doped carbon was prepared via thermal treatment of metal-organic frameworks and boric acid, which exhibits abundant hierarchical pore structure (micropore, mesopore and macropore) and suitable defect construction, promoting ion diffusion/charge transfer and providing more rapid surface pseudocapacitance reaction. More obviously, when the optimized B, N dual doped carbon was used as cathode in A-ZCHS and ZHS, more capacitive charge storage and rapider electrochemical kinetics can be observed in A-ZCHS than in ZHS. Therefore, the optimized A-ZCHS displays a high energy density of 115.7 Wh kg−1 at the power density of 711.6 W kg−1 with excellent stability, which is much better than most of ZHSs reported previously. The A-ZCHS should be a promising candidate for energy storage applications.

Summary The enantiomeric excess phenomenon in spontaneous chiral symmetry breaking (SCSB) is a crucial issue in the origin of homochirality in nature, whereas chiral inorganic compounds have long been reckoned as racemates. Here, we report the SCSB in the self-assembly of cadmium chalcogenide nanorods, leading to chiral biases away from the racemate. In the presence of achiral organics, helical CdSe@CdS nanorods (HCCNs) with unidirectionally rotated crystal lattices along the rod axis were stochastically formed on the epitaxial interface of the {111}cub/{0001}hex planes. The stability of helical dislocation structures, as supported by a theoretical analysis of their binding energies, suggested the possibility of the emergence of helical structures in an achiral environment. Hierarchical chiral films induced by simple solvent evaporation self-assembly of HCCNs exhibited spontaneous enantiomeric excess between batches, which was speculated to be originated from the enantiomeric excess seed assembly that induce one-handedness dominated system based on the majority rules.

Good knowledge of the redistribution characteristic of solute elements is essential for the design and the production of new alloying systems. Part I of this series demonstrated the deviations of m...

Microsegregation is an inherent phenomenon that occurs during the solidification of steel and can result in multiple casting defects. To explain and predict the microsegregation phenomenon, the ana...

Chirality is an indispensable integral of biological system. As an important part of organisms, chiral organic structure of bone has been extensively investigated. However, the chirality of bone minerals is unclear and not fully determined. Here, we report nine levels of fractal-like chirality of bone minerals by combining electron microscopic and spectrometric characterizations. The primary helically twisted acicular apatite crystals inside collagen fibrils and between fibrils merge laterally to form secondary helical subplatelets. The chiral arrangement of several subplatelets forms tertiary spiral mineral platelets. Further coherent stepwise stacking of mineral platelets with collagen fibrils leads to quaternary to ninth levels, which reconciled the previous conflicting models. The optical activities in the UV-visible, infrared and terahertz regions demonstrated chirality from atomic to macroscopic scales based on circularly selective absorption and Bragg resonance at different levels of chirality. Our findings provide new insight into the structural integrity of bone, osteology, forensic medicine and archaeology and inspire the design of novel biomaterials.

This work aimed to proposing a new strategy for preparing the mullite-ZrO2 porous fibrous ceramic used as alternative matrix material for oil-water separation by the aqueous gel-casting method. The properties of the fabricated porous fibrous ceramics in terms of microstructure, phase composition, apparent porosity, bulk density and compressive strength were investigated and the separation behavior was predicted by analyzing the structural changes. It is demonstrated that the phase composition of green bodies consisted of bayerite, boehmite, ZrSiO4 and YSZ, and the sintered sample contained mullite, ZrO2 and YSZ. As the YSZ fibers increased, the porosity of the fabricated porous ceramic increased with the maximum value of 70.65% due to the formation of more pores caused by YSZ fibers. Moreover, a significant increase in compressive strength (up to 9.52–21.86 MPa) was observed with the increase of YSZ fibers. Therefore, the fabricated porous ceramics could be appropriative for advanced applications of separation membranes for oil-water separation.

Half-metallic materials are theoretically predicted to be metallic and insulating, which have not been confirmed experimentally, and the predictions are still in doubt. We report the resistance-chiral anisotropy (R-ChA), i.e., chirality-dependent electrical conductivity, in chiral mesostructured Fe3 O4 films (CMFFs) grown on the substrates via a hydrothermal method using amino acids as symmetry-breaking agents. Two levels of chirality exist in the CMFFs: primary distortion of the crystal lattice forms twisted nanoflakes, and secondary helical stacking of nanoflakes forms fan-shaped nanoplates. At temperatures below 30 K, the CMFFs exhibited metallic conductivity and insulation for one handedness and the other, respectively. The chirality-dependent effective magnetic fields were speculated to stabilize the opposite spin in the antipodal chiral frame, which led to the free transport of electrons in one handedness of the chiral structure and immobility for the other handedness.

Antibiotic abuse resulted in the emergence of multidrug-resistant Gram-positive pathogens, which pose a severe threat to public health. It is urgent to develop antibiotic substitutes to kill multidrug-resistant Gram-positive pathogens effectively. Herein, the antibacterial dialdehyde nanocrystalline cellulose (DNC) was prepared and characterized. The antibacterial activity and biosafety of DNC were studied. With the increasing content of aldehyde groups, DNC exhibited high antibacterial activity against Gram-positive pathogens in vitro. DNC3 significantly reduced the amounts of methicillin-resistant Staphylococcus aureus (MRSA) on the skin of infected mice models, which showed low cytotoxicity, excellent skin compatibility, and no acute oral toxicity. DNC exhibited potentials as antibiotic substitutes to fight against multidrug-resistant bacteria, such as ingredients in salves to treat skin infection and other on-skin applications.

Adsorptive separation is an appealing technology for propylene and propane separation; however, the challenge lies in the design of efficient adsorbents which can distinguish the two molecules having very similar properties. Here we report a kinetically amplified separation by creating wiggling mesopores in structurally robust carbon monoliths. The wiggling mesopores with alternating wide and narrow segments afford a surface area of 413 m2 g-1 and a tri-modal pore size distribution centered at 1.5, 4.2 and 6.6 nm, respectively. The synergistically kinetic and equilibrium effects were observed and quantitatively assessed, which together ensured a remarkable propylene/propane selectivity up to 39. This selectivity outperformed not only the available carbon adsorbents but also highly competitive among the dominated crystalline porous adsorbents. In addition, the wiggling mesoporous carbon adsorbent showed excellent dynamical separation stability, which ensured its great potential in practical molecular separations.

MXenes, as recently emerging lamellar two-dimensional (2D) materials of transition metal carbides and/or nitrides, have attracted intensive attention for various applications in sensors, catalysis, energy storage, and biomedicine owing to their fascinating and technologically useful properties. This review presents the current progress of MXene-based materials applied in the field of electrochemical sensors. Firstly, how synthetic strategies and surface modification affect the properties of MXene was emphasized. Secondly, MXene as an electrode material for constructing electrochemical sensors based on MXene nanocomposites, especially metal nanoparticles (MNPs)/MXene, conductive polymers (CPs)/MXene, and carbon materials/MXene nanocomposites, was well discussed. Finally, the challenges and outlooks in this field with possible solutions and future opportunities are discussed.

Ultrafine gold nanoclusters (Au-NCs) are susceptible to migrate and aggregate, even in porosity of many crystalline solids. N-heterocyclic carbenes (NHCs) are a class of structurally diverse ligands for stabilization of Au-NCs in homogeneous chemistry, showing catalytic reactivity in CO 2 activation. Herein, for the first time, we demonstrate a heterogeneous nucleation approach to stabilize ultrasmall and highly dispersed gold nanoclusters in a metal-free NHC-functionalized porous matrix. The sizes of gold nanoclusters are tunable from 1.3 nm to 1.8 nm based on the interpenetration of metal-organic framework (MOF) topology. Control experiments using amine or imidazolium-functionalized MOFs afforded aggregation of Au species. The resultant Au-NC@MOF composite exhibits steady and excellent activity in photocatalytic CO 2 reduction, superior to the control mixtures without NHC-ligand stabilization. The mechanistic studies reveal the synergistic catalytic effect of MOFs and Au-NCs through the MOF-NHC-Au covalent bonding bridges.

Biological scaffolds with hyperbolic surfaces, especially single gyroid and single-diamond structures, have sparked immense interest for creating novel materials due to their extraordinary physical properties. However, the ability of nature to create these unbalanced surfaces has not been achieved in either lyotropic liquid crystals or block copolymer phases due to their thermodynamical instability in these systems. Here, we report the synthesis of a porous silica scaffold with a single-diamond-surface structure fabricated by self-assembly of the poly(ethylene oxide)-b-polystyrene-b-poly(L-lactide) and silica precursors in a mixed solvent of tetrahydrofuran and water. The single-diamond structure with tetrahedral interconnected frameworks was revealed by the electron crystallographic reconstruction. We assume that the formation of single networks is induced by the structural transition and related to the energetic change due to the fluctuations of the Gaussian curvature. This work may provide new insights into these biologically relevant surfaces and related self-assembly systems.

The development of materials integrated with ultrasmall multi-metal nanoparticles (UMMNs) and mesoporous zeolite is a considerable challenge in chemistry and materials science. We designed a trifunctional surfactant, in which the pyridyl benzimidazole in the hydrophobic tail generates the mesopores through π–π stacking; the diquaternary ammonium in the hydrophilic headgroup direct the formation of MFI zeolite sheets and the nitrogen atoms in the heterocyclic rings coordinate with various metal ions to form UMMNs confined in the zeolite matrix after calcination and reduction. A library of 56 UMMNs confined within both micropores and mesopores of MFI zeolites (MMZs) with 4 mono-, 14 bi- and 38 tri-metallic nanoparticles (sizes of 1.3–4.7 nm) of combinations of Rh, Pd, Pt, Au, Fe, Co, Ni, Cu and Zn were made. An improved catalytic performance was exhibited in the sequence of Rh-MMZ, This work was supported by the National Natural Science Foundation of China (Grant No. 21533002, 21931008, S.C.; 21873072, 21922304, L.H.; 21850410448, 21835002, A.M.). To the Centre for High-resolution Electron Microscopy (CħEM), supported by SPST of ShanghaiTech University under contract No. EM02161943, to the Spanish Ministry of Science (RYC2018-024561-I) and to the regional government of Aragon (DGA E13_20R).

The effective separation of photogenerated carriers plays a vital role in photocatalytic reactions. In addition to the intrinsic driving force of photocatalysis, an external field generating an enh...

Spin polarisation is found in the centrosymmetric nonferromagnetic crystals, chiral mesostructured NiO films (CMNFs), fabricated through the symmetry-breaking effect of a chiral molecule. Two levels of chirality were identified: primary nanoflakes with atomically twisted crystal lattices and secondary helical stacking of the nanoflakes. Spin polarisation of the CMNFs was confirmed by chirality-dependent magnetic-tip conducting atomic force microscopy (mc-AFM) and magnetic field-independent magnetic circular dichroism (MCD). Electron transfer in the symmetry-breaking electric field was speculated to create chirality-dependent effective magnetic fields. The asymmetric spin-orbit coupling (SOC) generated by effective magnetic fields selectively modifies the opposite spin motion in the antipodal CMNFs. Our findings provide fundamental insights for directional spin control in unprecedented functional inorganic materials.

The effect of thermal treatments on mechanical properties was systematically investigated in Ni/Mo multilayers with a constant modulation period (160 nm) prepared by magnetron sputtering deposition. A supermodulus effect was found in the annealed multilayers as compared to the as-deposited state. A large tensile stress development was observed in the multilayers. The evolution of grain-boundary (GB) wetting was observed at the interfaces of the multilayers, which results in an enhanced modulus based on the mechanism of GB-wetting-induced interfacial stress/strain. The GB wetting phenomenon was further supported by a thermodynamic calculation. The results not only bring clear evidence of the important role of interfacial structures in governing the elastic behavior of metallic multilayers, but also allow designing the multilayers with special properties through atomic diffusion and wetting at the interfaces based on the thermodynamic calculation.

The lamellar precursor of the FER type zeolite (PREFER) was applied to develop the interlayer expanded zeolite IEZ (interlayer-expanded zeolite)-FER (D4h) with extra-large pores through hydrothermal acid treatment-assisted molecular alkoxysilylation, using 1,3,5,7-tetramethyl cyclotetrasiloxane (D4h) as a silylating agent to interconnect neighboring zeolitic layers. The interlayer expanded structure was well preserved after calcination at 823 K, yielding a hydrophilic material denoted as IEZ-FER(D4h-B). The as-made IEZ-FER(D4h) exhibits expanded interlayer spacing along the a-axis. The 4-membered rings (4MR) exist in IEZ-FER(D4h) as the secondary structure building units, while the methyl groups therein attached result in the hydrophobic properties. The newly formed channel systems are composed of intersecting 14MR and 12MR pores along the [001] and [010] directions, respectively, which are larger than those of the conventional 3D FER. The powder XRD patterns determine that IEZ-FER(D4h) has a crystalline structure with the IMM2 space group and unit cell parameters of a = 28.0285(39) A, b = 14.0921(6) A, c = 7.4395(3) A.

Stille cross-coupling reactions catalysed by an ideal catalyst combining the high activity of homogeneous catalysts and the reusability of heterogeneous catalysts are of great interest for C–C bond formation, which is a widely used reaction in fine chemistry. Despite great effort to increase the utilization ratio of surface metal atoms, the activity of heterogeneous catalysts under mild conditions remains unsatisfactory. Herein, we design a proof-of-concept strategy to trigger the room-temperature activity of heterogeneous Au catalysts by decreasing the electron density at the interface of a rationally designed Schottky heterojunction of Au metals and boron-doped carbons. The electron-deficient Au nanoparticles formed as a result of the rectifying contact with boron-doped carbons facilitate the autocleavage of C–Br bonds for highly efficient C–C coupling reactions of alkylbromides and allylstannanes with a TOF value of 5199 h−1 at room temperature, surpassing that of the state-of-the-art homogeneous catalyst.

Gas-liquid volumetric liquid-phase mass transfer coefficient (k L a) was studied in a slurry bubble column at the conditions mimicking Fischer–Tropsch synthesis. To avoid the hydrodynamic disturbances due to the gas switching, oxygen enriched air dynamic absorption method was used. Influence of reactor models (CSTR, ADM and RCFD) on the volumetric mass transfer coefficient was investigated. Effect of operating pressure, superficial gas velocity and solids loading were investigated. From the reactor models investigated, it is recommended to use ADM model for k L a study. If the CSTR model is used, applicability of the model should be checked. With increase in the superficial gas velocity and operating pressure, volumetric liquid-phase mass transfer coefficient increases, while it decreases with the solids loading corroborating with the literature.

The ever-growing demand for wearable electronic devices is stimulating the development of novel materials for fabrication of flexible electronics. Among all promising candidates, polysaccharide-bas...

Label-free electrochemical immunosensors (EIs) are simple and sensitive in cancer diagnosis. Electrode materials which can offer a large specific area and excellent electrical conductivity play a critical role in the fabrication of EIs. In our study, ce-MoS2/AgNR composite was synthesized via Van der Waals force and electrostatic interaction between chemical exfoliated MoS2 nanosheets (ce-MoS2) and Ag nanorods (AgNRs). The conductivity of ce-MoS2/AgNR composite was almost three times higher than single ce-MoS2 because of the synergistic effect between ce-MoS2 and AgNRs. Furthermore, AgNRs could effectively inhibit the stacking of MoS2 nanosheets. The EIs for prostate-specific antigen (PSA) detection were fabricated based on ce-MoS2/AgNR composite. The fabricated EIs retained a wide linear response range (0.1–1000 ng/ml), low sensitivity (0.019 μA/(ng ml−1)), and low detection limit (0.051 ng/ml) for the detection of PSA. Therefore, the EIs based on screen-printed electrode (SPE) and ce-MoS2/AgNR composite could be applied to clinical diagnosis of prostatic cancer and have potential application in the detection of other cancer biomarkers.

During the annealing of Ni and Ni-Mo films, a {110} texture, usually considered to be both of high surface energy and high strain energy, was found to develop. Quantitative thermodynamic model calculations showed that the anomalous formation of this {110} texture originates fundamentally from the grain yielding anisotropy of Ni. Based on extensive grain yielding anisotropy model calculations, a “texture map” based on {111}, {100}, and {110} textures was constructed to predict the texture transition temperatures for different film thicknesses. A kinetic analysis of the texture evolution in the films is further presented, revealing that the texture evolution is controlled by the self-diffusion of atoms at grain boundaries. These findings pave the way for the achievement of unusual surface orientations through the quantitative texture design of thin films.

An ideal oil/water separation membrane should possess the characteristics of high flux and separation efficiency, recyclability, as well as good mechanical stability. Herein, a facile method is applied to fabricate a Janus polylactic acid (PLA) fibrous membrane for efficiently separating surfactant-stabilized oil/water mixtures. The Janus PLA fibrous membrane architecture was prepared by electrospinning a PLA/carbon nanotubes (CNTs) fibrous membrane and the subsequent electrospinning of a PLA/SiO2 nanofluids (nfs) membrane onto one side of the PLA/CNTs fibrous membrane. Due to the strong electrostatic interaction between SiO2 nfs and CNTs, synchronous enhancement and plasticization of PLA fibrous membranes were achieved, which was far superior to that reported in the literature. The introduction of CNTs had caused an upshift of the hydrophobicity of the PLA/CNTs fibrous membrane (water contact angle (WCA) > 140°). In contrast, SiO2 nfs bearing long-chain organic anions and cations located onto the surface of the fibers during electrospinning to achieve superhydrophilicity (WCA ≈ 0°). Benefiting from completely opposite wettability on both sides of the Janus membrane, the obtained asymmetric Janus membranes exhibited a high flux (1142-1485 L m-2 L-1) and excellent oil/water separation efficiency (>99%), which were superior to those reported for other Janus membranes. Furthermore, the Janus membranes showed desirable flux recovery without any treatment (>80% for water-in-oil emulsions and >90% for oil-in-water emulsions, respectively, after 11 cycles), showcasing promising applications for water treatment in the future.

An unprecedented four-dimensional (4D) printing process allowing high-performance and shape memory thermoset to be printed, for the first time, by fused deposition modeling (FDM) with isotropic properties has been achieved. Bisphenol A-based epoxy and benzoxazine were formulated to a low-temperature thermoplastic and high-temperature thermoset resin, which is melt-extrudable and can be postcured into covalently cross-linked material. Carbon nanotube (CNT) was added in the resin to work as both mechanical enhancement filler and rheology modifier to prevent shape deformation during postcuring process. The cross-layer reaction fuses individual layers into an integrity, thus eliminating layer delamination induced by FDM, offering isotropic mechanical properties regardless of the printing orientations. The highly cross-linked network provides outstanding mechanical strength and superb thermal stability. The excellent shape memory performance with fast recovery rate and large recovery degree is also obtained in the three-dimensional (3D) printed composites.

Titania has received considerable attention as a promising anode material of Li-ion battery (LIB). Controlling the structure and morphology of titania nanostructures is crucial to govern their performance. Herein, we report a mesoporous titania scaffold with a bicontinuous shifted double diamond (SDD) structure for anode material of LIB. The titania scaffold was synthesized by the cooperative self-assembly of a block copolymer poly(ethylene oxide)-block-polystyrene template and titanium diisopropoxide bis(acetylacetonate) as the inorganic precursor in a mixture solvent of tetrahydrofuran and HCl/water. The structure shows tetragonal symmetry (space group I41/amd) comprising two sets of diamond networks adjoining each other with the unit cell parameter of a = 90 nm and c = 127 nm, which affords the porous titania a specific surface area (SSA) of 42 m2·g−1 with a mean pore diameter of 38 nm. Serving as an anode material of LIB, the bicontinuous titania scaffold exhibits a high specific capacity of 254 mAh·g−1 at the current density of 1 A·g−1 and an alluring self-improving feature upon charge/discharge over 1,000 cycles. This study overcomes the difficulty in building up ordered bicontinuous functional materials and demonstrates their potential in energy storage application.

In this paper, the electronspun Polylactic acid (PLA)/TiO2 nanofluids (nfs) fibrous membrane with good toughness, hydrophilicity and antibacterial activities are fabricated by taking full advantages of solvent-free TiO2 nfs with amphiphilicity and ionic conductivity. The resulting PLA/TiO2 nfs fibrous membrane exhibits excellent mechanical performance with a tensile strength and elongation at break of 3.68 MPa and 97.32 MPa at 5 wt% loading, respectively, which is 4 and 8 times higher than that of pure PLA, respectively. Additionally, TiO2 nfs can migrate onto the surface of PLA fibers during electrospun process, which significantly enhanced hydrophilicity, antistatic property, moisture sorption capacity and wicking properties of PLA fabrics. Meanwhile, the membrane also showed ultrafast water filtration of 3500 L m−2 h−1 driven by gravity force, which is 10–12 times higher than that of commercial ultrafiltration membrane. After ion-exchange reaction with salt solution, excellent antibacterial activity (against E. coli and S. aureus was 95% and 99.9%, respectively) and separation efficiency (above 90% on E. coli) of the obtained fabrics are also achieved. Overall, organic nfs are an idea candidate for fabricating hydrophilic PLA based biodegradable fabric that can be applied in contaminated water treatment, antibacterial textiles and biodegradable absorption materials.

Unit-cell-thin zeolitic nanosheets have emerged as fascinating materials for catalysis and separation. The controllability of nanosheets stacking is extremely challenging in the chemistry of two-dimensional zeolitic materials. So far, the organization of zeolitic nanosheets in hydrothermal synthesis has been limited by the lack of tunable control over the guest-host interactions between organic structure-directing agents (OSDAs) and zeolitic nanosheets. Here, we report a direct synthetic methodology that enables systematic manipulation of the aluminosilicate MWW-type nanosheets stacking. Variable control of guest-host interactions is rationally achieved by synergistically altering the charge density of OSDAs and synthetic silica-to-alumina composition. These finely-controlled interactions allow the successful preparation of series of three-dimensional (3D) zeolites with MWW-layer stacking in wide ranges from variations of disorder to fully-order, leading to tunable catalytic activity in cracking reaction. These results highlight unprecedented opportunities to modulate zeolitic nanosheets arrangement in 3D zeolites whose structure can be tailored for catalysis and separation.

While there is an emerging good theoretical understanding of how hard impenetrable spherical nanoparticles diffuse in unentangled and entangled polymer liquids, the analogous problem for soft perme...

Binary media structural planes exist widely in natural rock mass and rock mass engineering, which are weak points of engineering and important factors that affect engineering stability. Thus, the mechanical behavior analysis of binary media has important engineering significance. The influence of the parallel bonding modulus ratio of binary media on the shear mechanical behavior of structural planes was investigated from the perspective of microscopic parameters on the basis of the numerical calculation method of discrete elements. A binary media model, including a flat structural plane, was established using the particle flow code. By changing the microscopic parameters, direct shear tests under different constant normal loads were conducted on the models with different parallel bond modulus ratios. The changes in shear stress, number of cracks, and normal displacement with shear displacement were recorded to investigate the influence of the parallel bond modulus ratio on the failure mode and failure development rule of the binary media. Two main results were obtained. First, the difference in modulus between two sides of the structural plane of the binary media greatly influences the peak strength, failure area, crack development, and location of the failure plane in the shear behavior of the binary media. Second, an increase in normal load will reduce the influence of the parallel bond modulus ratio on peak shear strength. Empirical formulas for strength parameters and modulus difference were proposed in this study on the basis of the simulation results. The shear strength calculation formula, including the microscopic parameters, was proposed and verified.

The self-powered sensors are more and more important in current society. However, detecting both light and temperature signals simultaneously without energy waste and signal interference is still a challenge. Here, we report a ZnO/graphene nanocomposite foam-based self-powered sensor, which can realize the simultaneous detection of light and temperature by using the conjuncted photo-thermoelectric effect in ZnO–graphene nanocomposite foam sensor. The output current under light, heating and cooling of the device with the best ZnO/graphene ratio (8:1) for the foam can reach 1.75 µA, 1.02 µA and 0.70 µA, respectively, which are approximately three fold higher than them of devices with other ZnO/graphene ratios. The ZnO–graphene nanocomposite foam device also possesses excellent thermoelectric and photoelectric performances for conjuncted lighting and heating detection without mutual interference. The ZnO–graphene nanocomposite foam device exhibits a new designation on the road towards the fabrication of low cost and one-circuit-based multifunction sensors and systems.

Quasicrystals attract considerable attention due to their unique physical and structural properties. An increasing number of quasicrystals have been reported from self-assembly processes in soft ma...

Semiconducting ternary metal oxide thin films exhibit a promising application for solar energy conversion. However, the efficiency of the conversion is still limited by a band gap of a semiconductor, which determines an obtainable internal photovoltage for solar water splitting. In this report the tunability of the tin tungstate band gap by O2 partial pressure control in the magnetron co-sputtering process is shown. A deficiency in the Sn concentration increases the optical band gap of tin tungstate thin films. The optimum band gap of 1.7 eV for tin tungstate films is achieved for a Sn to W ratio at unity, which establishes the highest photoelectrochemical activity. In particular, a maximum photocurrent density of 0.375 mA cm−2 at 1.23 VRHE and the lowest reported onset potential of −0.24 VRHE for SnWO4 thin films without any co-catalyst are achieved. Finally, we demonstrate that a Ni protection layer on the SnWO4 thin film enhances the photoelectrochemical stability, which is of paramount importance for application.

Highlights The development of bismuth ferrite as a multiferroic nanomaterial is summarized.The morphology, structures, and properties of bismuth ferrite and its potential applications in multiferroic devices with novel functions are presented and discussed.Some perspectives and issues needed to be solved are described., Multiferroic nanomaterials have attracted great interest due to simultaneous two or more properties such as ferroelectricity, ferromagnetism, and ferroelasticity, which can promise a broad application in multifunctional, low-power consumption, environmentally friendly devices. Bismuth ferrite (BiFeO3, BFO) exhibits both (anti)ferromagnetic and ferroelectric properties at room temperature. Thus, it has played an increasingly important role in multiferroic system. In this review, we systematically discussed the developments of BFO nanomaterials including morphology, structures, properties, and potential applications in multiferroic devices with novel functions. Even the opportunities and challenges were all analyzed and summarized. We hope this review can act as an updating and encourage more researchers to push on the development of BFO nanomaterials in the future.

Nature has created innumerable life forms with miraculous hierarchical structures and morphologies that are optimized for different life events through evolution over billions of years. Bicontinuous cubic structures, which are often described by triply periodic minimal surfaces (TPMSs) and their constant mean curvature (CMC)/parallel surface companions, are of special interest to various research fields because of their complex form with unique physical functionalities. This has prompted the scientific community to fully understand the formation, structure, and properties of these materials. In this review, we summarize and discuss the formation mechanism and relationships of the relevant biological structures and the artificial self-assembly systems. These structures can be formed through biological processes with amazing regulation across a great length scales; nevertheless, artificial construction normally produces the structure corresponding to the molecular size and shape. Notably, the block copolymeric system is considered to be an applicable and attractive model system for the study of biological systems due to their versatile design and rich phase behavior. Some of the phenomena found in these two systems are compared and discussed, and this information may provide new ideas for a comprehensive understanding of the relationship between molecular shape and resulting interface curvature and the self-assembly process in living organisms. We argue that the co-polymeric system may serve as a model to understand these biological systems and could encourage additional studies of artificial self-assembly and the creation of new functional materials.在数十亿年的进化过程中, 大自然创造了多种复杂的多级结构, 这些多级结构针对不同的生命活动具有组装体所不具有的优异性能. 其中双连续立方结构通常能够用三周期极小曲面(TPMS)和它们的常平均曲率曲面(CMC)/平行曲面共同来描述. 它们具有复杂的结构和独特的物理性质, 得到了各个研究领域的广泛关注, 同时也对它们的形成机理、 晶体结构和性能表现的研究提出了新的挑战. 本文对生物和人工自组装系统中相关曲面结构的形成机理及相互关系进行了总结和讨论. 在生物体中具有几百纳米大尺度的多种生物立方膜及相关结构, 而人工合成体系中往往只能形成与分子大小及曲率相对应的结构. 值得注意的是, 嵌段共聚物体系具有灵活的可设计性和丰富的相行为, 为研究生物体系提供了一个理想的模型. 对这两个体系中发现的一些现象进行比较和讨论, 可以为全面理解分子形状和由此产生的界面曲率之间的关系, 进而理解生物体的自组装过程提供新的思路.

State-of-the-art electron crystallography when combined with geometric techniques to model curved surfaces enables an in-depth study of twinning defects in bicontinuous cubic structures., Bicontinuous cubic structures in soft matter consist of two intertwining labyrinths separated by a partitioning layer. Combining experiments, numerical modelling and techniques in differential geometry, we investigate twinning defects in bicontinuous cubic structures. We first demonstrate that a twin boundary is most likely to occur at a plane that cuts the partitioning layer almost perpendicularly, so that the perturbation caused by twinning remains minimal. This principle can be used as a criterion to identify potential twin boundaries, as demonstrated through detailed investigations of mesoporous silica crystals characterized by diamond and gyroid surfaces. We then discuss that a twin boundary can result from a stacking fault in the arrangement of inter-lamellar attachments at an early stage of structure formation. It is further shown that enhanced curvature fluctuations near the twin boundary would cost energy because of geometrical frustration, which would be eased by a crystal distortion that is experimentally observed.

A solid‐to‐hollow evolution in macroscopic structures is challenging in synthetic materials. A fundamentally new strategy is reported for guiding macroscopic, unidirectional shape evolution of materials without compromising the material's integrity. This strategy is based on the creation of a field with a “swelling pole” and a “shrinking pole” to drive polymers to disassemble, migrate, and resettle in the targeted region. This concept is demonstrated using dynamic hydrogels containing anchored acrylic ligands and hydrophobic long alkyl chains. Adding water molecules and ferric ions (Fe3+) to induce a swelling–shrinking field transforms the hydrogels from solid to hollow. The strategy is versatile in the generation of various closed hollow objects (for example, spheres, helix tubes, and cubes with different diameters) for different applications., A solid dynamic hydrogel prepared by micellar copolymerization of stearyl methacrylate, acrylamide, and acrylate acid in the presence of sodium dodecyl sulfate surfactant macroscopically self‐transforms to form a hollow interior. The hydrogel mimics the function of living systems, which can adapt to environmental changes as part of their biofunctions.