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The first-principles calculations demonstrate that covalently bonded (cb) heterojunction and van der Waals (vdW) heterojunction can coexist in silicene/CeO2 heterojunctions, due to the different stacking patterns. Especially, the cb heterojunction with band gap of 1.97 eV, forms a type-II heterojunction, exhibits good redox performance and has high-effective optical absorption spectra, thus it is a promising photocatalyst for overall water splitting. Besides, for the vdW heterojunction, the Dirac cone of silicene is well kept on CeO2 semiconducting substrate, with a considerable energy gap of 0.43 eV, which can be an ideal material in building silicene-based electronic device. These results may open a new gateway in both of nanoelectronic device and energy conversion for silicene/CeO2 nanocomposites.

Polyvinyl alcohol (PVA)/laponite (LP) nanocomposite coatings were fabricated via a facile one-step coassembly process. The formed nanocoatings contain a high concentration of LP nanosheets, which can be well aligned along the substrate surface during the coassembly process. Due to the highly orientated structure, the flexible nanocoatings exhibit ultra-high transparency and superior mechanical properties, and can also act as excellent gas barriers. Such nanocoatings can be exceptional candidates for a variety of applications, such as food packaging.

Gas-in-liquid foam templating is considered as a promising method for commercial-scale production of porous materials. However, Ostwald ripening occurs frequently during the preparation, which could bring about inhomogeneous bubbles with large sizes and deteriorate the performance of resultant products. To tackle this challenging task, we report a gelation network-triggered morphology-regulation strategy during the foaming process. As an exemplar, boehmite sol was incorporated into the andalusite suspension to stabilize the foam framework. After casting, the wet foam was able to maintain its overall shape, since andalusite particles were anchored onto the gas-liquid interface by the gelation network during mechanical frothing. The samples calcined at 1400°C feature homogeneous bubble with hierarchical porous architecture, smaller pore size with a mean value of 5.32 μm and robust compressive strength of 11.97MPa at a porosity level of 84 %. Our approach substantially broadens the design philosophy of high performance porous ceramics.

Structural design/doping strategy is an efficient method to prepare electrolytes with high oxygen ionic conductivity, but there is still hindrance for solid oxide fuel cell (SOFC) commercialization. Recent advances in semiconductor ionic materials have developed a novel strategy in designing low-temperature electrolyte materials. Here, a heterostructure composite of LSFC (La0.6Sr0.4Fe0.8Cu0.2O3-δ) and SDC (Sm0.2Ce0.8O2−δ) is developed. The LSFC-SDC composite exhibits a high ionic conductivity, >0.1S/cm at 550 °C. With symmetrical NCAL (Ni0.8Co0.15Al0.05LiO2-δ)-coated electrode, cells with SDC-LSFC electrolyte exhibit high open-circuit voltage (OCV), and achieve a significant power improvement (>1000 mW/cm2) compared with pure SDC electrolyte at 550 °C. The short-term stability result has proven the operating ability of SDC-LSFC electrolyte under fuel cell environment (H2/air). This work demonstrates a new developing route of low-temperature solid oxide fuel cell (LTSOFC), which is different from the conventional SOFC.

The p-i-n junction structure has garnered great interest from researchers due to its increased photoactive area and wider space charger region compared with that of the p-n junction. Herein the ult...

Metal–organic frameworks (MOFs) with plenty of active sites and high porosity have been considered as an excellent platform for the electroreduction of CO2, yet they are still restricted by the low...

The silver nanowire (AgNWs) / cotton fiber was used as a conductive substrate with high conductivity charge transfer. Then the polyaniline (PANI) molecular chain was fixed on the AgNWs / cotton fiber by in-situ polymerization to prevent its dedoping and improve its cyclic properties. Thus the flexible capacitor electrode material with conductive, specific capacity and cyclic properties was obtained. The results showed that when the mass ratio of KH-560 to AgNWs/cotton fiber was 3:1, the grafting rate of epoxide group on the modified AgNWs/cotton fiber was the highest. When the mass ratio of aniline to modified AgNWs cotton fabric was 3:1, the PANI content of in-situ polymerization on the fabric surface was the highest, 20.83%. The specific capacity of PANI/AgNWs/cotton fiber electrode material was the highest, 154 F/g, after 5000 cycles of charging and discharging, the specific capacity could keep 96%. It is worth mentioning, the introduction of PANI and AgNWs could significantly improve the wear resistance of cotton fiber, the friction resistance of the cotton fabric increased to 36,000 times. It is provided a new idea for design a flexible capacitor electrode material integrating electrical conductivity and cyclic stability.

Supercapacitors possessing fast-charging characteristics and long lifespan are becoming increasingly important for powering portable and smart energy storage devices, and combining capacitive and battery-type materials into an integrated device is an effective method for increasing the overall performance of capacitors. Silicene is being designed as a cathode for the development of enhanced capacitance and ultra-cycle stable zinc-ion hybrid capacitors. Possessing a maximum areal capacity of 14 mF cm-2, a maximum power density of 9 mW cm-2, capacitance retention of 112% even after 10 000 cycles, and an unexpectedly high energy density of 23 mJ cm-2, this achievement of the zinc-ion hybrid capacitor would be superior to that of previously reported silicon-based supercapacitors. The DFT calculations further reveal that Zn ions dominate the capacitive behavior of the silicene electrode. The support association between silicene and zinc-ion hybrid capacitors so that they can take advantage of each other's strengths, which takes electrochemical energy technology to a stage, offering a straightforward proposal for integration and implementation of silicon-based materials.

The microstructure, martensitic transformation and mechanical/functional properties of Ti–Ta-Hf alloys with various thermo-mechanical treatments were investigated. The results reveal that the hot-rolling could refine the grain size and introduce a certain number of defects, resulting in the disappearance of martensitic transformation. The as-casted and solution treated Ti–Ta-Hf alloys were composed of α'' martensite phase and smaller volume of β phase. In contrast, the grain size of solution treated Ti–Ta-Hf alloy was slightly less than that of as-casted Ti–Ta-Hf alloy. This should be responsible to the higher yield stress and superior strain recovery characteristics for solution treated Ti–Ta-Hf alloy. The yield stress for the dislocation slip and the maximum recoverable strain of solution treated Ti–Ta-Hf alloy were 723 ​MPa and 5.06%, respectively.

Surface modification is a main approach for natural polymers to gain flame retardancy. Developing a green coating system to endow natural polymers with flame retardancy and wash-durability is extremely challenging. Herein, a sandwich-like structured nanocoating system with mutual restricted network through electrostatic interaction, hydrogen bonding, and chemical bonding were designed via multi-layered coating and UV curing. The coated natural cotton fabrics demonstrated exellent flame retardancy, wash durability, and hydrophobicity. The chemicals involved include montmorillonite (MMT), ammonium polyphosphate (APP), acrylated polyurethane (PU), branched polyethylenimine (bPEI), and polydimethylsiloxane (PDMS). The concentration of bPEI governed the wash durability of the coated fabrics, and those samples with a higher concentration of bPEI possessed better wash durability. Meanwhile, bPEI served as a flammable resource to deteriorate the flame retardant performance. The systematic evaluations of the coated fabrics after washing demonstrated that this coating system can maintain balanced wash durability and flame retardancy.

In this work, the crystal structure and hydrogen storage properties of V35Ti30Cr25Fe10, V35Ti30Cr25Mn10, V30Ti30Cr25Fe10Nb5 and V35Ti30Cr25Fe5Mn5 BCC-type high entropy alloys have been investigated. It was found that high entropy promotes the formation of BCC phase while large atomic difference (δ) has the opposite effect. Among the four alloys, the V35Ti30Cr25Mn10 alloy shows the highest hydrogen absorption capacity while the V35Ti30Cr26Fe5Mn5 alloy exhibits the highest reversible capacity. The cause of the loss of desorption capacity is mainly due to the high stability of the hydrides. The higher room-temperature desorption capacity of the V35Ti30Cr25Fe5Mn5 alloy is due to higher hydrogen desorption pressure. After pumping at 400 °C, the hydrides can return to the original BCC structure with only a small expansion in the cell volume.

In the present work, the microstructure features, martensitic transformation, mechanical properties and strain recovery characteristics of Ti-Ta based shape memory alloys were tailored by changing Hf contents. The single α´´ martensite phase was dominated in Ti-Ta alloy with 2 at.%H f. Upon Hf content exceeded 2 at.%, β phase started to appear. Moreover, the amount of β phase gradually increased with Hf content increasing. The martensitic transformation temperatures continuously decreased with the increased Hf content, which was attributed to the rising of valence electron concentration. Meanwhile, Hf addition improved the thermal cycling stability of Ti-Ta alloys due to the suppression of ω precipitation. The yield stress of Ti-Ta based alloys firstly decreased and then increased with Hf content increasing. In addition, the completely recoverable strain of 4 % can be obtained in Ti-Ta alloy with 6 at.% Hf as a consequence of the higher critical stress for dislocation slip. Besieds, the Ti-Ta based alloy containing 8 at.% Hf had the superior superelasticity behavior with the fully recoverable strain of 2 % at room temperature.

Nickel metal hydride (Ni-MH) rechargeable batteries hold an important position in the new-energy vehicle market owing to their key technology advantages. Their negative electrode materials—hydrogen storage alloys (HSAs) are always on the spotlight and are the key to compete with the burgeoning Li-ion batteries. Here, for the first time we report a series of biphase supperlattice HSAs with a (La,Mg)2Ni7 matrix phase and a novel (La,Mg)7Ni23 secondary phase. The biphase alloys show discharge capacities of 402–413 mAh g−1 compared with 376–397 mAh g−1 of the other multi- or single-phase alloys. These values are among the highest for superlattice HSAs. In addition, the alloy with 15.4 wt.% (La,Mg)7Ni23 phase exhibits good high rate dischargeability due to the proper compromise between the amount of crystal boundaries and equilibrium plateau voltage. The cycling stability of the biphase alloys is lower than that of the single-phase alloy but is till higher than the multiphase alloy. The novel superlattice biphase alloys with superior overall electrochemical properties are expected to inspire further design and development of HSAs as advanced electrode materials for power batteries.

The compression behaviour of fine-grained soils is mainly controlled by pore collapse, while the compression behaviour of sands is mainly governed by grain breakage. For soils containing both fine and coarse soil particles such as quartz and calcite grains, the compressibility may depend on both pore collapse and grain breakage. In this study, the compressibility of two natural soils reported in the literature was first analysed in this sense, showing the effect of grain breakage on the compressibility of soils. To further verify this phenomenon, high-pressure oedometer tests were carried out on a natural stiff clay containing a significant fraction of granular elements. The obtained results confirmed the significant effect of grain breakage. In order to better understand the role of fines in the grain breakage phenomenon, artificial sand–clay mixtures were prepared with different fine fractions and tested in oedometer. Results show that the compression behaviour of sand–clay mixtures can be roughly divided into three zones according to the fine fractions: at low fine fractions, the compression behaviour is governed by grain breakage; at high fine fractions, the compression behaviour is governed by the pore collapse of fines; and at medium fine fractions, both pore collapse and grain breakage affect the compression behaviour. In this last case, pore collapse occurs first, letting grains to be well in contact either directly (grain–grain contacts) or indirectly (grain–fine grain contacts) to activate the grain breakage phenomenon upon further loading. This is consistent with the identified compression behaviour of natural fine-grained soils.

Rare-earth AB5-type hydrogen storage alloys are widely studied due to their extensive application potentials in hydrogen compressors, heat pump, Ni–MH batteries etc. However, their shortcomings such as plateau splitting and capacity degradation during hydrogen absorption/desorption hinder their practical applications. In this paper, we study the effect of Mn partial substitution for Ni on the plateau characteristics and long-term cycling performance of LaNi5-xMnx alloys. It is found that Mn addition expands the lattice interstitial for hydrogen accommodation, thus prohibiting the plateau splitting phenomenon. In addition, the substitution of Mn for Ni stabilizes the crystal structure of the alloys against hydrogen absorption/desorption, thus relieving the capacity degradation. The capacity retention of the alloys at the 1000th cycle (S1000) increases from 83.2% (x = 0) to 94.0% (x = 0.75). But when x reaches 1, the hydrogen desorption reversibility is reduced due to the low plateau pressure, resulting in a slight decrease in capacity retention.

Semiconductor-based electrolytes have significant advantages than conventional ionic electrolyte fuel cells, especially for high ionic conductivity and power outputs at low temperatures (

Cold plasma (CP) treatment for enhancing functional and cooking properties has been investigated on less rice varieties and delays the industrial adoption of this technology. This study treated three types (short-, medium-, and long-kernel) of milled rice from six Chinese varieties with helium plasma (Radio frequency, 13.56 MHz, 140 Pa) at a combination of watt and time, and evaluated the cooking properties, cooked rice texture, kernel appearance quality, and surface morphology, as well as flour thermal and thermomechanical properties. CP treatment at 120 W for 20 s significantly decreased the cooking time and the hardness of cooked rice while increasing adhesiveness, elasticity, and gruel solid loss. CP did not significantly change the appearance of milled rice, except for chalky rice rate, and kept the peak temperature and enthalpy of gelatinization in rice flour. 120W–20s CP significantly increased rice dough development and stability time, starch gelatinization maximum torque, and starch breakdown, but decreased the stability of protein network and starch retrogradation. As CP power strength increased from 120 to 520 W; the surface rupture of a rice kernel became more severe, and small particles aggregated on the rough surface. Compared with the 0 h sample of 120W–20s CP treatment, the repeating CP treatments at 24 h, 48 h, and 30 d significantly decreased water contact angle and free fatty acid content, but increased water absorption rate and chalky rice rate. These results suggest that 120W–20s helium CP improved the cooking properties of milled rice via leading to the rough kernel surface, higher water absorption rate, weak protein network, and a higher speed of starch gelatinization.

As the electrode material of supercapacitor, MnO2 materials have attracted extensive concern and its electrochemical performance has been continuously optimized, but the kinetic analysis is rarely discussed. Herein, a-MnO2 nanowires with a uniform morphology were synthesized by hydrothermal method, which exhibits proven electrochemical property like outstanding circulation stability, demonstrated rate performance and high specific capacitance. In addition, diffusion-controlled Faradaic procedure and surface capacitance action were calculated and analyzed in detail.

Super ionic channel or shuttle correlated with interfacial engineering of nanocomposite structure and semiconductor-based material electrolytes has shown great potential in electrochemical applications, such as photochemical water splitting or low temperature advanced fuel cell. By adjusting apriority composition between n and p components, the up-to-date semiconductor-ionic membrane fuel cells (SIMFCs) exhibit the improved performance, especially for high ionic conductivity and power outputs at lower temperature. Facing the commercialization of novel advanced ceramic cells, a combined literature survey and phenomenological analysis is proposed to interpret the difference between the current-voltage curve and stability performance of low temperature solid oxide fuel cell (LTSOFC). Meanwhile, it is experimentally determined that the time constant, which is closely related to the interfacial structure and heterostructure, has played a great role in the cell properties. Herein, steady state instead of transient characteristic is preferred, dedicating to provide much more reliable data. Among several prototype cells on semiconductor-based electrolyte, only the candidate that can resist the high current operation shows suppressing inside electronic leakage and survives in short-term test. The results illustrate that though semiconductor-based nanocomposite or heterostructure is an effective methodology in developing low temperature ceramic fuel cells, its durability and the risk of short-circuit should be taken with much care.

To investigate the effect of linear, rod and granular nano-silver structures on the electrical conductivity and wear resistance of cotton fabrics, silver nanowires (AgNWs), silver nano-rods (AgNRs) and silver nanoparticles (AgNPs) were separately obtained by solvothermal method, and then adsorbed on the cotton fabrics. Compared with AgNRs and AgNPs that silver nanowires could form network structure on the cotton fabrics. As the ratio of nano-sliver length to diameter increases, the effective adsorption mass of nano-sliver on the cotton increases, improving the conductivity of the textile electrode. No matter how many times of rubbing, it had no effect on the square resistance of the AgNWs/cotton. The cotton fabrics treated with silver nanowires had the best performances and wear resistance.

Photonic crystal supraparticles (PCSs) obtained by self-assembly of colloidal building blocks hold promise for applications in various areas. The majority of PCSs are based on isotropic colloidal spheres, fundamentally limiting their structural and functional diversity. Herein we demonstrate the magnetic assembly of Janus PCSs with increased complexity from a colloidal mixture of nonmagnetic spheres and magnetic ellipsoids. The key to this strategy is the use of non-uniform magnetic fields to simultaneously induce the phase separation of binary particles and assist the subsequent crystallization of anisotropic magnetic ellipsoids. Due to their different crystalline structures, the nonmagnetic and magnetic regions of Janus PCSs exhibit isotropic and anisotropic optical properties, respectively. Moreover, the structural colour can be tuned by magnetically controlling the orientation of supraparticles. Our study not only produces multi-functional PCSs with novel structures and properties but also provides a new model system for understanding the colloidal assembly of binary mixtures.

Porphyrin-based photocatalytic oxygen evolution (POE) has exhibited great potential in artificial photosynthesis; however, a few reports exist on efficient nanocatalytic systems due to the fast photoinduced charge recombination. Here, cobalt(III) tetraphenylporphyrin (CoP) nanowires (NWs) are first synthesized at a large-scale via a simple chemical reaction, and transformed in situ into zero-dimensional CoP/NGQDs nanocomposites by adding nitrogen-doped graphene quantum dots (NGQDs) as the template and dopant. Under the visible light irradiation, no detectable POE activity of CoP NWs is observed in an acid heterogeneous system, while the currently highest POE rate on the molecule (350 μmol g−1 h−1) is achieved with CoP/NGQDs as the photocatalyst. Systematic experiments reveal that the NGQDs-limiting self-assembly of CoP molecules along the axial direction and subsequent formation of Z-scheme CoP/NGQDs heterojunctions are crucial for efficient POE. The nanostructures lead to enough exposure of the central Co atom as POE active sites and longer recombination lifetime of the photoinduced charge in CoP/NGQDs (87.8 ps) than that in CoP NWs (32.2 ps) due to the generation of (CoP+·NGQDs−)* exciplex. This work provides a new strategy to use a nature-like semiconductor molecule as a direct catalyst for artificial photosynthesis.

Halide perovskites are widely used as an absorbing or emitting layer in emerging high-performance optoelectronic devices due to their high absorption coefficients, long charge carrier diffusion lengths, low defect density and intense photoluminescence. Si-based materials (c-Si, a-Si, SixNy, SiCx and SiO2) play important roles in high performance perovskite optoelectronic devices due to the dominance of Si-based microelectronics and the important role of Si-based solar cells in photovoltaics. Controlling the preparation of perovskite materials on the dominant Si optoelectronics platform is a crucial step to realize practical perovskite-based optoelectronic devices. This review highlights the recent progress in Si-based perovskite optoelectronic devices including perovskite/Si tandem solar cells, perovskite/Si photodetectors, perovskite/Si light emitting diodes and optically pumped lasers. The remaining challenge in Si-based perovskite optoelectronic devices research are discussed.

A Ni-based metal organic framework (Ni-BDC) and subsequently derived NiFe-LDH were studied to overcome the defect of the low availability of active sites for the oxygen evolution reaction (OER) during the water splitting process. This work reported NiFe-LDH nanosheets with an ultra-thin structure through an in situ surface-conversion derived from Ni-BDC. The unique structure and characteristic morphology were confirmed using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy, and the OER activities of the catalysts were systematically studied. The obtained results indicated that the synthesized Ni-BDC@NiFe-LDH-2 showed excellent OER activity, with a low overpotential of 272 mV at a current density of 10 mA cm−2, a small Tafel slope of 45 mV dec−1, and excellent stability, owing to the addition of abundant metal sites and the expansion of the electron transport channels during the conversion process to form the ultra-thin layer structure. This work provides a novel strategy for the application, design, and manufacture of metal organic framework (MOF)-based high-efficiency active materials.

Rice Husks (RHs) are one of the most abundant sources of biomass in the world due to rice consumption. Lignocellulose and silica are two of the main components of RHs, which allow RHs to be applied in different areas. Lignocellulose can be partially dissolved in 1-butyl-3-methylimidazolium chloride (BMIMCl), which is a simple way of competing with the traditional extraction methods that suffer from high chemical consumption. A lignocellulose freeze gel is obtained via a cyclic liquid nitrogen freeze-thaw (NFT) process. Multi-functional self-assembled lignocellulose aerogel is obtained after CO2supercritical drying. Based on the aerogel’s special properties, two routes are developed for practical applications. On one hand, the aerogel is coated to exhibit a superhydrophobic property that can be applied as an absorbent for oil spills. On the other hand, a carbon aerogel is synthesized via a pyrolysis process, resulting in a porous amorphous carbon. The residue after partially dissolving lignocellulose in BMIMCl is further calcined to obtain amorphous silica nanoparticles, achieving a comprehensive application of RHs.Graphical abstract

Methanol crossover through polymer electrolyte membranes (PEMs) is a major concern in fuel cell research. In order to address this problem, a sulfonated poly(fluorenyl ether ketone) (SPFEK)/α-zirconium phosphate (ZrP) nanocomposite membrane containing 2.0 wt. % of ZrP nanosheets was prepared by casting a dimethylacetamide (DMAc) dispersion containing SPFEK and exfoliated ZrP nanosheets. The membrane was characterized and tested as a PEM in a single direct methanol fuel cell (DMFC) at 80 °C. The introduction of ZrP nanosheets improved the oxidative stability and reduced methanol permeability and water uptake of the PEM. The SPFEK/ZrP nanocomposite membrane led to the best cell performance among the single cells using SPFEK/ZrP nanocomposite membrane, SPFEK, and Nafion® 117. The maximum power densities obtained for the cells composed of the above three membranes were 51.3, 41.4, and 43.6 mW/cm2, respectively.

We presented the solution of deformation-induced precipitation after homogenization to enhance the mechanical properties of Mg–6Zn alloys. The results show that the improved strategy exhibits more effective strengthening role than grain refinement methods based on low-temperature severe plastic deformation under the same strain. The low-temperature deformation with larger extrusion ratio results in massive nano-sized precipitates and excellent mechanical properties with the yield strength of 355 MPa and the ultimate tensile strength of 405 MPa. The increased mechanical properties are strong and tough enough to resist the stress and not be worn away when the alloy nail penetrates through the pig thigh bone, potentially extending more orthopedic surgery applications for Mg–Zn alloys.

The non-precious materials with iron-pyrrolic nitrogen-carbon (Fe–N–C) moiety have attracted an increasing attention on the CO2 reduction reaction (CO2RR). However, the influence of iron valence state and environmental synergy is not still clear. Here, iron phthalocyanine (FePc) molecule with an intrinsic Fe–N4–C moiety is enough dispersed on graphene as the single-atom iron catalyst through a facile chemical method. The FePc-graphene composites with different FePc content and iron valence state are synthesized to investigate their catalysis for the CO2RR to CO. The onset overpotential of 190 mV and Faradaic efficiency of >90% may be achieved in the optimal composites. Experimental and calculational results prove the positive role and synergy of Fe(II)Pc with Fe(III)Pc and graphene. The formation of ∗COOH intermediate is confirmed to be the rate-limiting step. The theoretical calculation reveals that Fe(II)Pc should have higher activity than Fe(III)Pc, and Fe(II)Pc/FePc(III) dimer may be better than individual one. This work clearly exhibits the effect of Fe2+/3+- pyrrolic N4–C on the CO2RR.

A series of V2O5/WO3-TiO2 and V2O5/SiO2-WO3-TiO2 catalysts containing 2 wt%, 3.5 wt% and 5 wt% V2O5, respectively, were prepared by impregnation method. The NH3-SCR activity and thermal stability of the catalysts were investigated. It is noted that both V2O5 loading and SiO2 modification could affect the thermal stability of the V2O5/WO3-TiO2 catalysts. Increasing V2O5 loading improved the low temperature SCR activity of the catalysts in fresh state, but high V2O5 loading aggravated the deactivation of the catalysts upon aging. With relatively high V2O5 loading (3.5 wt% and 5 wt% V2O5), V2O5/SiO2-WO3-TiO2 showed remarkably improved thermal stability than V2O5/WO3-TiO2 NH3-SCR catalysts. The catalysts were characterized by BET, XRD, SEM, Raman, XPS, H2-TPR and NH3-TPD. The results indicated that high V2O5 loading on V2O5/WO3-TiO2 catalyst can accelerate the phase transition of anatase TiO2 to rutile TiO2 upon thermal aging, which resulted in the loss of surface area and consequently led to the deactivation, while introduction of silica prevented the phase transition of TiO2, therefore enhancing the thermal stability of the catalysts.

Engineering highly porous SiC foams with interconnected cellular architecture and satisfactory compressive strength for the practical applications remains a challenging task. In the current work, SiC foams bonded by in-situ formed mullite phase were fabricated via polyurethane foaming using boehmite sol-coated SiC powder as the raw material. The strategy in the current work endowed the resultant products with ultrahigh porosity, interconnected pore structure, and a robust mullite bonding phase among the SiC particles. The resulting products with this cellular architecture possessed a high porosity level of 88.5% and maintained a robust compressive strength of 2.56 MPa. Our results showed that as-prepared products are promising for practical applications in the filtration, adsorption and catalytic areas.

The design and synthesis of new filtration materials for high-temperature particulate matter capture are of both technological and scientific importance but still remain a challenging task. In the current work, we presented an approach for the manufacturing of highly porous SiC cellular ceramics by combining polyether polyol-modified carbon black with polyurethane foaming method. Hydroxyl groups were introduced to the surface of carbon black to prevent agglomeration. As-obtained SiC cellular ceramic possed three-dimensional interconnected reticular architecture with the abundant micron-sized window on its cell wall. The resulting porous SiC ceramic exhibited a high removal efficiency (95.8%) with extremely low pressure drop (38 Pa). The successful fabrication of such fascinating material may provide new insights for high-temperature particulate matter filtration.

Engineering high performance cellular ceramics with both ultralow density and satisfactory compressive strength for practical applications still represents a grand challenge. Herein, alumina-based cellular ceramics bonded by in-situ formed mullite phase were constructed by Al2O3–Si-boehmite particle-stabilized foams. The gelation of boehmite sol improved the stability and harnessed the deformation of dried Al2O3–Si composite foam. The oxidation of silicon and further generation of in-situ mullite phase enhanced the chemical bond between alumina particles on cell walls, resulting in the superior mechanical properties. As an exemplar, the resulting cellular ceramic possessed the robust compressive strength of 2.26 MPa at a high porosity of 87.8%. The gelation-assisted Al2O3–Si particle-stabilized foams provide a facile and convenient strategy for construction of composite ceramic foams with high porosity and robust strength.

A gelcasting system of alumina utilizing tartaric acid as the dispersant and glutaraldehyde as the crosslinker is reported, in which glutaraldehyde can polymerize itself and react with tartaric acid, thus forming a three-dimensional network. Measurement of zeta potential and viscosity shows good dispersion ability of tartaric acid. Shear modulus during gelation demonstrates its good gelation strength and fast gelation speed at room temperature. Moreover, an effective way to control the gelation speed is provided to improve the feasibility of this method. Results indicate that this gelcasting method has the advantages of low viscosity, small amounts of additives and short forming time and is a promising method to fabricate green bodies with large sizes and complex shapes.

Semiconductor ionic electrolytes have obtained much attention because of good ionic conductivity and electrochemical performance. Novel semiconductor ionic NSDC (Ce0.8Sm0.2O2-δ-Na2CO3)-LCCN (LiCo0·225Cu0·075Ni0·7O3-δ) composite materials have been adopted as electrolyte membrane for the first time, in which symmetrical cell composed of NSDC-LCCN membrane is constructed with Ni0·8Co0·15Al0·05LiO2 (NCAl)-pasted Ni foam electrodes. An open circuit voltage (OCV) above 1 V and improved power density are obtained in the NSDC-LCCN cells, which confirms the functionality of the proposed semiconductor ionic materials. Meanwhile, X-ray diffractometer (XRD) and Scanning electron microscope (SEM) analyses identify the phase purity and homogenous nanocomposite morphology of all the NSDC-LCCN materials samples with various mass ratios. The performance illustrated by much more steady instead of transient state evaluation reveals that 3NSDC-LCCN composite electrolyte is most optimum, and the corresponding cell exhibits a considerable maximum power density of 598 mW cm−2 at 550 °C, over five times of that of pure NSDC electrolyte cells. Short-term duration test of 3NSDC-LCCN cell at 550 °C shows that the cell could steadily operate up to ~9 h without obvious degradation at a remarkable current density of 469 mA cm−2, which indicates that NSDC-LCCN composite electrolyte is a promising material for low temperature solid oxide fuel cells.

Cellular ceramics with 3D network architecture are attracting ever-increasing attention because of their great application potential in multiple fields. Unfortunately, a daunting challenge still remains for fabricating such materials. A novel methodology is provided in the current work to construct cellular ZrO2 ceramics with such architecture by combining polyurethane foaming and chemical modification technology. Stearic acid grafted ZrO2 powder with improved dispersibility allows the successful assembly into the polyurethane porous framework. The obtained cellular materials possess a three-dimensional network architecture with windows on the cell wall. The resulting ZrO2 cellular ceramic with such unique structure exhibits a relatively high porosity (83.5%) and robust compressive strength (13.5 MPa), which outperforms most of the existing ZrO2-based counterparts. With above advantages, we envision that as-prepared products are promising for filter applications.

A new gelcasting approach of alumina inspired by Isobam was designed utilizing a polyelectrolyte dispersant named BTT, which is able to form cross-links via thiol-ene reaction with pentaerythritol tetrakis(2-mercaptoacetate). Measurement of zeta potential and viscosity shows good dispersion ability of BTT in 52 vol% alumina suspensions. The flow curves and shear modulus of wet green bodies during gelation demonstrate its high gelation strength in comparison with Isobam. The analysis of effects of addition of ammonium citrate tribasic into the system indicates that a polymer-particle double network is supposed to form during gelation. Elastic part and viscous part of gelation strength of the system are mainly dominated by interaction between polyelectrolyte and particles and cross-linking respectively, which accounts for the existence of both high gelation strength and flexibility of wet green bodies fabricated in this approach.

Ag deposited ZnO (Ag/ZnO) nano materials with different Ag molar content were prepared via chemical precipitation method. The morphology of nano ZnO was rod like, while the size was 170 nm in length and 30 nm in diameter. Silver nanoparticles were found to be spherical with the diameter about 15 nm. When it deposited on the surface of the nano ZnO, the size of the nano ZnO was almost unchanged when the doping amount is 2.5 %. All the samples were treated on cotton fabric, and the laden fabric had excellent performance on hydrophobicity, including UV resistance, antibacterial activity and anti-mildew. The contact angle of fabric loaded with 3 % Ag/ZnO was 139 compare to nano ZnO, which was 103°. The fabric loaded with Ag/ZnO had superior performance of UV resistance. With the increase of depositing amount, the antibacterial rates were promoted; the antibacterial rates against S. aureus, E. coil, and C. albicans of fabric with 3 % Ag/ZnO were promoted to 91 %, 96 % and 98 %. Moreover, Ag/ZnO gave cotton fabrics good anti-mildew performance, especially A. flavus, and its anti-mildew effect could reach 0 grade.

We herein report a novel hierarchically porous ceramic foams derived from boehmite gel foams, which possess both high porosity and superior strength. The gel foams show excellent printability due to its predominant stability, high yield stress and storage modulus, which endows such foam material ideal ink for 3D printing lightweight and complex-shape materials via direct ink writing approach. The 3D printed ceramic foams possess programmable architecture assembled by porous filaments, uniform macro-pores with tunable size in the range of 4∼70 μm, as well as nanoscale pores in cell wall, after sintering at relatively low temperature of 1200–1300 °C. In this way, ceramic foams with high strength were achieved, attributed to the tiny grains, large amount of grain boundaries, uniform pores and hierarchical pore structure. Notably, the foams sintered below 1200 °C have significant advantage on specific surface area, which could reach up to 300-400 m2/g.

Developing effective carbon materials for post-combustion CO2 capture (PCC) has received great attentions over many recent years, owing to their desirable adsorption–desorption performance and exceptional thermo-oxidative stability compared to virtually any other capture materials typically the wide array of amine-based sorbent materials. However, due to the nature of physical adsorption, virtually none of the carbon materials reported so far can be practically used for PCC applications without deep flue gas cooling to ambient or even lower temperatures in order to achieve appreciable levels of CO2 uptake capacities at low CO2 partial pressures. Here, we present a category of 3D hierarchical molecular sieving carbon architectures that are able to operate at realistic flue gas temperatures with exceedingly high reversible CO2 capacities. The breakthrough CO2-sieving carbon materials are prepared from using a cost-effective and commercially widely available precursor of polymeric polyisocyanurates with a facile one-step compaction–activation methodology. Tested at sensible flue gas temperatures of 40–70 °C and a low CO2 partial pressure of 0.15 bar, the best performing materials are found to have exceedingly high reversible CO2 capacities of up to 2.30 mmol g−1 at 40 °C and 1.90 mmol g−1 at 70 °C. Advanced characterisations suggest that the unique geometry and chemistry of the easily available precursor material coupled with the characteristics of the compaction–activation protocol used are responsible for the CO2-sieving structures and capacities of the 3D carbon architectures. The findings essentially change the general perception that carbon-based materials can hardly find applications in post-combustion capture due to their low CO2 uptake capacity at low CO2 partial pressures and realistic flue gas temperatures.

Amyloid fibrils, implicated in health and diseases, commonly exhibit a periodic twist trait relevant to the structures and dynamics of the fibrils. However, the origins and modulations of fibril twist in complex in vivo environments are not yet fully understood. Here we highlight an important factor that causes twist variations in amyloid fibril structures-the presence of surrounding surfaces. Using cholesterol-containing lipid bilayers with varying cholesterol contents, we have demonstrated via atomic force microscopy that amyloid-β peptide fibrils initiated on membranes increase their average pitch size of twisting periodicity as the cholesterol content increases. These surface-induced twist variations arise from the enhanced hydrophobic interactions between the fibril and the surface distorting the torsional elastic energy of the fibril twisting as supported by a theory of an elastic model. These findings not only provide an important insight into fibril polymorphism phenomena resulting from the surface effects but also suggest a novel solution to modulate filament twisting on the nanoscale for biomaterials applications involving nanoscale features.

A series of cerium-doped iron–titanium composite oxide catalysts (FeCeaTi, a = 0.1–1.0) prepared by a urea homogeneous precipitation method were investigated for selective catalytic reduction of NOx with NH3 (NH3-SCR). Over all the FeCeaTi samples, a promotion effect for NOx reduction was induced by the introduction of cerium, with the FeCe0.3Ti catalyst exhibiting the best catalytic performance, even at a high GHSV of 250 000 h−1. As indicated by kinetic studies, interestingly, the FeCe0.3Ti catalyst exhibited a higher activation energy for the NH3-SCR process while possessing a pre-exponential factor three orders of magnitude higher than that of FeTi. Going deeper, extensive characterization including N2-physisorption, XRD, Raman, NH3/NOx-TPD, XPS, EPR, and H2-TPR was carried out. XRD and Raman results showed that the introduction of suitable amounts of Ce into the FeTi samples promoted the dispersion of Fe and Ti. Such higher dispersion of these two components increased the capacities for NOx adsorption and activation and weakly bonded ammonia over FeCe0.3Ti, thus promoting the occurrence of the L–H pathway of NH3-SCR at low temperatures. H2-TPR results indicated that the reduction of FeCe0.3Ti occurred at a higher temperature than that of FeTi, which may be a reason for its higher activation energy for NH3-SCR.

Quasi-solid-state Zn-air batteries (ZABs) have shown extraordinary promise for electrochemical energy storage, but are usually limited to relatively low-rate ability (< 10 mA cm−2), which caused by the sluggish O2 electrocatalysis and unstable electrochemical interface. Here we present an ultrahigh-rate and robust quasi-solid-state ZABs integrated with the atomic Co-N4 sites anchored on wrinkled nitrogen-doped graphene (Co SA-NDGs) cathode and the modulated H-bond network of polyacrylamide (PAM) organohydrogel electrolyte with. The quasi-solid-state ZABs exhibit the highest cycling rate of 100 mA cm−2 over 50 h at room temperature, which is nearly an order of magnitude higher than results reported previously. Meanwhile, the exceptional cycling stability more than 300 h (0.5 mA cm−2) with high-capacity retention at -60 oC and all-temperature adaptability (-60 to 60°C) are also demonstrated. The integral design towards high performance Zn-air batteries using atomic site catalyst and electrolyte with good interface stability broaden the scope of application.

Mo:BiVO4 nanoparticles were employed as an optical modulator in a Q-switched all-solid-state Tm:YAP laser for the first time. The nonlinear optical parameters of Mo:BiVO4 nanoparticles in the 2-μm region were characterized by measuring nonlinear transmission. Saturation intensity was 718 MW/cm2, and the modulation depth was 12.3%. A stable pulse sequence was acquired with a 70.08 kHz maximum repetition rate and an 821 ns pulse width. The maximum output average power was 153 mW, corresponding to 2.18 μJ single pulse energy and 2.67 W peak power. Although the response wavelength of Mo:BiVO4 is in visible light region, our experimental results demonstrates that a saturable absorption effect for wavelengths much longer than visible light (2 μm wavelength) is still possible due to sub-bandgap absorption. Therefore, we experimentally proved that Mo:BiVO4 nanoparticles are a great candidate for use as an optical modulator of a 2-μm pulsed laser.

Summary Metal- and nitrogen-coordinated nanocarbons (M-N/Cs) represent the most promising nonprecious catalysts for the oxygen reduction reaction (ORR), but it remains challenging to simultaneously achieve high intrinsic activity, fast mass transport, and efficient utilization of active sites in a single catalyst. Herein, we design an Fe-N/C catalyst consisting of edge-hosted Fe-N3 sites dispersed on multiscale porous carbon frameworks (eFe-N3/PCF). The low coordination and edge effect of the Fe-N3 moieties endow eFe-N3/PCF with high intrinsic activity, while the enriched nanopores enable improved mass transport and atom utilization efficiency. When evaluated by a rotating disk electrode in the base, eFe-N3/PCF presents early-onset and half-wave potentials of 1.090 and 0.934 V versus the reversible hydrogen electrode, respectively. Furthermore, when employed as gas diffusion electrodes, eFe-N3/PCF displays excellent mass-transport efficiency that enables high-rate/power capabilities at practically high current densities. This work opens up opportunities for designing high-performance ORR electrocatalysts toward applications in diverse energy conversion and storage technologies.