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Aiming to elucidate the hydrogen absorption/desorption cycling properties of Mg-based alloys with in-situ formed Mg2Ni and LaHx (x = 2, 3) nanocrystallines, the hydrogen storage cycle stability, hydriding/dehydriding cycling kinetics and thermodynamic stability of the experimental alloys have been investigated in detail. The results show that the Mg–Ni–La alloys exhibit improved hydrogen storage cycling properties and can remain storage hydrogen above 5.5 wt% after 200 cycles. With the increase of cycling numbers, the dehydrogenation rates of the experimental samples increase firstly and then gradually decrease, and eventually maintain relative stable state. Microstructure observation reveals that powders sintering and hydrogen decrepitation both exist during hydrogen absorption/desorption cycles due to repeated volume expansion and contraction. Meanwhile, the in-situ formed LaHx (x = 2, 3) and Mg2Ni nanocrystallines stabilize the microstructures of the particles and hinder the powders sintering. After 200 cycles, the average particle size of the experimental samples decreases and the specific surface area apparently increases, which leads to the decomposition temperatures of MgH2 and Mg2NiH4 slightly shift to lower temperatures. Moreover, Mg2Ni and LaHx (x = 2, 3) have been proven to be stable catalysts during long-term cycling, which can still uniformly distribute within the powders after 200 cycles.

Recent studies have shown that layered compound EuCd2As2 could exhibit diverse topological states depending on the different magnetic structures, such as Weyl semimetal, Dirac semimetal, topological insulator, etc. In order to further study the interplay between magnetism and topology of EuCd2As2, it is necessary to figure out its magnetic structure. Here, by magnetization (M) measurements and negative magnetostriction (λ) along the [001] direction measured by scanning tunneling microscope on EuCd2As2 single crystals, we observe field-induced metamagnetic phase transition from A-type antiferromagnetic (AFM) ground state to field-polarized state, with canted AFM (CAFM) state in between. Magnetization and magnetostriction are more sensitive to the in-plane field than the out-of-plane field, indicating the magnetic moments lying in the ab plane. The absence of abrupt jump on M-H and λ-H curves demonstrates the phase transition is a second-order type. In CAFM state, M increases linearly with the field and λ is proportional to M 2 . Tunneling conductance spectra show the field-induced evolution of the electronic density of states. Our results provide experimental evidence for understanding the magnetic structure of EuCd2As2.

The random mobility of charge carriers is a main factor causing the low photocatalytic efficiency of g-C3N4. Thus, the controllable migration of charge carriers is a rational strategy to suppress the charge recombination and facilitate charge separation. Herein, an ethylenediamine modified g-C3N4 displays improved photocatalytic activity. The excellent charge separation efficiency is confirmed to be a key factor for the enhancement. The observation from TEM image after photo-deposited Pt nanoparticles and DFT calculations verify the accumulation of electrons on some area of surface. The increased -NH2 groups significantly tune the electronic structure of g-C3N4 after modification. The generation of midgap state also affect the charge separation. Our reports provide a simple method to manage the migration of charge carriers and enables electrons directional transfer, which suppress the recombination and improve the photocatalytic activity.

Metal rich-sulfides, with remarkable theoretical capacity, still suffer from the disolving of polysulfides and sluggish kinetics. Electrocatalysts, as the vital meditors, have been applied in Li-S systems with notable improvements, but scarcely explored for ions-storage battery. Herein, for introducting cation-tunable MOx (M=Mn/Fe/Co/Ni) as electrocatalysts, various MoS2@MOx are designed through chemical-precipitation and thermal-treatment manners. Benefitting from the high affinity of MoS2 and MOx, the interfacial chemical bonds Mo-S-M are established, boosting the improvement of ions/electrons transferring and structural integrality. Owing to the evolution of outer orbitals and ionic radius, the capturing and conversion of Li2S8 are tailored in order of Fe2O3>MnO>CoO>NiO. Supported by unique 3d-orbital/ion-radiu and Mo-S-Fe bonds, the ultra-fast ability of MoS2@Fe2O3 remains ∼612 mAh g−1 after 3,000 loops even at 5.0 A g−1, meanwhile delivering ∼800 mAh g−1 at 0.5 A g−1 in full-cell. Assisted by detailed kinetic behaviors and theoretical calculations, the redox reaction mechisms are clearly proposed, whilst the reduced Gibbs free energy (-1.25 of Fe2O3) serves crucial roles in the reaction (Li2S8 → Li2S6). This work is expected to shed light on the in-depth understanding of fourth-periods MOx electrocatalysts, and offers more possibilities for designing advanced metal-sulfides electrodes. MoS2 nanosheets uniformly anchored with MOx (M=Mn, Fe, Co, Ni) were rationally engineered, accompanied by the establishment of Mo-S-M interfacial chemical bonds. The electrocatalytic abilities of introduced MOx were successfully tailored by the evolution of cationic outer orbitals and ionic radius, inducing the fascinated catalytic conversion behaviors.

Development of good support materials is widely adopted as a valid strategy to fabricate high performance electrocatalysts for the ethanol oxidation reaction (EOR). In this study, the small diameter Ti3C2Tx MXene thin nanosheets inserted into three-dimensional nitrogen-doped grapheme (NG) was constructed via a facile hydrothermal method and employed as support materials for anchoring Pd nanocrystals (Pd/Ti3C2Tx@NG). The obtained-Pd/Ti3C2Tx@NG as EOR electrocatalyst in alkaline media outperforms the commercial Pd/C with better electrocatalytic activity, enhanced long-term stability and high CO tolerance. The Ti3C2Tx inserted into NG probably plays a key role for enhancing the properties of the synthesized-catalyst. Inserting Ti3C2Tx into NG allows the electrocatalysts to have high porosity, surface hydrophilicity, sufficient number of anchor sites for Pd nanocrystals and modifies its electronic properties, which can promote the electrocatalytic activity and durability. The enhanced EOR performance endows Pd/Ti3C2Tx@NG with great application potential in fuel cells as an anode catalyst. Furthermore, the prepared Ti3C2Tx@NG is also suitable in various desired applications, especially other oxidation reactions.

Photocatalytic water spitting is one way of hydrogen production from energy conservation and emission reduction. However, the activities of most photocatalytic materials need to be enhanced by cocatalysts. In this study, we explored to control the photocatalytic hydrogen evolution (PHE) ability of cadmium sulfide (CdS) without any cocatalysts by temperature and largely improve its photocatalytic ability. It was experimentally found the activity of CdS without cocatalysts under heating conditions (100 °C) was much higher than that at room temperature, and increased first and then decreased, with a maximum at 50 °C (169716 umol/h, 68.2 % , λ = 450 nm). Therefore, it is convenient to control the hydrogen production activity of CdS by temperature. The large increment of photocatalytic activity was realized because the temperature complemented the shortcomings of semiconductors in light absorption, and together with light radiation, increased the electron migration rate and density, quantity of surface adsorbed H

The aimlessness in the selection of dielectric absorbing materials and the regulation of complex permittivity consumes time and resources. It is an effective way to construct electromagnetic wave (EMW)-absorbing materials dominated by dielectric loss to select materials and adjust complex permittivity based on theory. With sulfide as an example, a hollow ZnO/ZnS composite was constructed using ZnO as a hard template. Subsequently, based on the diverse binding ability of Cu and Zn ions to S ions, the compositions, interfaces, and defects of the sample were simultaneously regulated. There was competition and synergy between the relaxation process caused by the defects and interfaces and the conductivity loss, resulting in the regulation of complex permittivity. Furthermore, the hollow structure effectively reduced the density of the material and improved the impedance matching ability of the sample. As a result, the effective absorption bandwidth (EAB) of the hollow nanoflower ZnO/ZnS/CuS composite reached 5.2 GHz (from 12.8 to 18 GHz) with a matching thickness of 1.59 mm. This method provides a direction for ameliorating the complex permittivity of EMW-absorbing materials dominated by dielectric loss to realize broadband absorption.

Though the function of peptide based nanotubes are well correlated with its shape and size, controlling the dimensions of nanotubes still remains a great challenge in the field of peptide self-assembly. Here, we demonstrated that the shell structure of nanotubes formed by a bola peptide Ac-KI3VK-NH2 (KI3VK, in which K, I, and V are abbreviations of lysine, isoleucine, and valine) can be regulated by mixing it with the salt sodium tartrate (STA). The ratio of KI3VK and STA had a great impact on shell structure of the nanotubes. Bilayer nanotubes can be constructed when the molar ratio of KI3VK and STA was less than 1:2. Both the two hydroxyls and the negative charges carried by STA were proved to play important roles in the bilayer nanotubes formation. Observations of different intermediates provided obvious evidence for the varied pathway of the bilayer nanotubes formation. Based on these experimental results, the possible mechanism for bilayer nanotubes formation was proposed. Such a study provides a simple and effective way for regulating the shell structure of the nanotubes and may expand their applications in different fields.

Dielectric loss is greatly important for electromagnetic wave absorption. However, the detailed mechanism for this interfacial polarization is still sorely lacking and the main contribution of dielectric loss in the supported materials has never been investigated until now. Here, we have designed a model dielectric material with a carbon-based supported structure in order to explain the main contribution of dielectric loss originated from its interfacial polarization. The experimental and theoretic results proved that the complicated nanoparticles (NPs) supported on carbon substrate (MOF-74-S1) with optimal particle distribution can form three kinds of interfacial polarizations compared with MOF-74-S2, which mainly contributes to the dielectric loss of the carbon-based composites. The optimal composition and distribution of the NPs bring enhanced dielectric loss and the best electromagnetic wave absorbing properties, with a minimum reflection loss of −33.5 dB and a broad effective absorption bandwidth of 7.6 GHz at a thickness of 2.3 mm. These findings indicate that the optimal distribution of nanoparticles is one of the promising methods to enhance the dielectric loss.

Aiming to gain insight on the hydrogen storage properties of Mg-based alloys, partial hydrogenation and hydrogen pressure related de-/hydrogenation kinetics of Mg–Ni–La alloys have been investigated. The results indicate that the phase boundaries, such as Mg/Mg2Ni and Mg/Mg17La2, distributed within the eutectics can act as preferential nucleation sites for β-MgH2 and apparently promote the hydrogenation process. For bulk alloy, it is observed that the hydrogenation region gradually grows from the fine Mg–Ni–La eutectic to primary Mg region with the extension of reaction time. After high-energy ball milling, the nanocrystalline powders with crystallite size of 12∼20 nm exhibit ameliorated hydrogen absorption/desorption performance, which can absorb 2.58 wt% H2 at 368 K within 50 min and begin to desorb hydrogen from ∼508 K. On the other side, variation of hydrogen pressure induced driving force significantly affects the reaction kinetics. As the hydrogenation/dehydrogenation driving forces increase, the hydrogen absorption/desorption kinetics is markedly accelerated. The dehydrogenation mechanisms have also been revealed by fitting different theoretical kinetics models, which demonstrate that the rate-limiting steps change obviously with the variation of driving forces.

Although lithium-ion batteries (LIBs) have many advantages, they cannot satisfy the demands of numerous large energy storage industries owing to their high cost, low security, and low resource richness. Aqueous zinc-ion batteries (ZIBs) with low cost, high safety, and high synergistic efficiency have attracted an increasing amount of attention and are considered a promising choice to replace LIBs. However, the existing cathode materials for ZIBs have many shortcomings, such as poor electron and zinc ion conductivity and complex energy storage mechanisms. Thus, it is crucial to identify a cathode material with a stable structure, substantial limit, and suitability for ZIBs. In this review, several typical cathode materials for ZIBs employed in recent years and their detailed energy storage mechanisms are summarized, and various methods to enhance the electrochemical properties of ZIBs are briefly introduced. Finally, the existing problems and expected development directions of ZIBs are discussed.

Novel double-ceramic-layer (DCL) thermal barrier coatings (TBCs) composed of (Yb0.1Gd0.9)2Zr2O7 (YbGZO) top layer and YSZ bottom layer were deposited via EB-PVD technology. The phase stabilities and thermo-physical properties of the YbGZO bulk ceramics as well as the diffraction peak constituent, elemental content, microstructure and thermal exposure behavior of DCL thermal barrier coatings were evaluated. After calcination from room temperature up to 1573 K, the YbGZO ceramic powders do not form new phases and still maintain excellent thermal stability while the thermal diffusivity of YbGZO bulk reaches the minimum value of 0.207 ± 0.004 mm2/s at 1273 K. Meanwhile, the thermal conductivity of YbGZO ceramics is in the range of 0.88–1.04 W/(m⋅K), which is correspondingly lower than that of YSZ bulk material ((1.20–1.46) W/(m⋅K)) due to the fact that the ceramic top layer of YbGZO has more irregular columns distribution and a larger intercolumnar gap. After spallation failure, DCL coating is mainly composed of YbGZO with fluorite phase and Y0.08Zr0.92O1.06 of tetragonal phase which the pyramidal morphologies on top have disappeared with an obvious densification of ceramic coatings. In comparison, the sintering behavior of YSZ coating is more serious than that of YbGZO coating. Moreover, the penetration of vertical microcracks through the whole ceramic coatings could promote the formation of oxygen diffusion channels and further accelerate the internal oxidation behavior of grain boundaries and voids within the bond coat. In addition, the irregular distribution of transverse microcracks has led to the transgranular fracture of columnar grains.

The α-Ni(OH)2 coated with manganese (Mn) materials was synthesized by the chemical precipitation method, and the electrochemical properties were investigated. The results showed that the ingredient of the coating is a mixture of MnO2 and Mn2O3, and the coating can inhibit the intercalated anions escape and stabilize the α-Ni(OH)2 phase structure in KOH alkaline solution. The coated electrodes have higher discharge capacities and higher capacity retention rates than the uncoated α-Ni(OH)2 electrode, the discharge capacity of Mn-coated electrodes is over 350 mAh g−1, and the capacity retention rate exceeds 92%, separately. The reason may be that the Mn coatings can block or decelerate water molecule and the anion to escape from the interlayers, therefore prevent α phase structural collapse and maintain high discharge capacity during a long lifespan cycle. Therefore, the Mn coating α-Ni(OH)2 is a promising candidate for high-power Ni-MH batteries.

Superfluous low-frequency microwave radiation becomes a serious problem gradually at current age, herein, the Sn-Fe-O multiphase compounds were combined with novel biochar by using Salvia miltiorrhiza Bunge's leaves as carbon source, which can realize the recycling of this useless Chinese medicinal waste for economy. Also, the influence of preparation process on the final components, structures and properties in composites have been evaluated, the P2 composite possesses the optimal electromagnetic absorbing property i.e. the maximum reflection loss achieves −45.09 dB at 0.48 GHz with efficient absorbing bandwidth of 0.14–1.16 GHz at the matching thickness of 2 mm, moreover, a broad efficient absorbing bandwidth of 0.86–3 GHz can obtained for only 0.71 mm as well. The outstanding absorption of this sample can be ascribed to the synergistic effect of multiple low-frequency absorption mechanisms such as nature resonance, eddy current, conduction and electron hopping, multi-ply interfacial polarization etc., suggesting its superiority for being applied as a new-type low frequency electromagnetic wave absorber for practical use.

Rechargeable aluminum batteries are believed as a promising next-generation energy-storage system due to abundant low-cost Al sources and high volumetric specific capacity. The Al-storage cathodes, however, are plagued by strong electrostatic interaction between host materials and carrier ions, leading to large overpotential and undesired cycling stability as well as sluggish ion diffusion kinetics. Herein, sulfur-linked carbonyl polymer based on perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) as the cathode materials for ABs is proposed, which demonstrates a small voltage polarization (135 mV), a reversible capacity of 110 mAh g−1 at 100 mA g−1 even after 1200 cycles, and rapid Al-storage kinetics. Compared with PTCDA, the sulfide polymer possesses higher working voltage because of its lower LUMO energy level according to theoretical calculation. The ordered carbonyl active sites in sulfide polymer contribute to the maximized material utilization and rapid ion coordination and dissociation, resulting in superior rate capability. Besides, the bridged thioether bonds endow the polysulfide with robust and flexible structure, which inhibits the dissolution of active materials and improves cycling stability. This work implies the importance of ordered arrangement of redox active moieties for organic electrode, which provides the theoretical direction for the structural design of organic materials applied in multivalent-ion batteries.

In an attempt to enhance the low-temperature dischargeability of A2B7-type hydrogen storage alloy, the addition of alane (AlH3) by convenient ball milling method was investigated based on La-Y-Ni superlattice alloy containing Y2Ni7-type phase and YNi3-type phase primarily. The maximum discharge capacity of the composite with doping 1 wt.% AlH3 increased by 364.2% reaching 208.9 mAh g−1 at 233 K compared with the pristine sample. The initial high-rate discharge capacity of doping 1 wt.% AlH3 sample reached 151.7 mAh g−1 at 4000 mA g−1 current density. The improvement could be ascribed to strengthening of hydrogen diffusion channel and acceleration of H-kinetics at low temperatures derived from formation of new porous structure and modification of lattice defects by dissolution of aluminum on the surface. It has made a powerfully contribution to a pace of commercialization of A2B7-type superlattice hydrogen storage alloy applying in high altitude or latitude regions.

Due to its high theoretical capacity (∼280 mA h g−1), lithium vanadium oxide (LiV3O8) is considered a promising electrode material for meeting the demands for a longer battery life. However, it still suffers from an inferior cycling stability and rate properties. Benefitting from the unique traits of rare earth metal La, La-doping was introduced to V-sites, leading to an expansion of the lattice volume and reduced particle size, and bringing about more oxygen defects for fast ion redox reactions. The considerable discharge capacity of optimized La-doped LiV3O8 could reach up to 308 mA h g−1, and the capacity could be kept at 252 mA h g−1 after numerous loops. Supported by a detailed analysis of the capacity curves, an improved redox activity of V5+ was strongly demonstrated. Moreover, compared to the basic materials, an increasing rate capacity located in the low potential range was detected, ascribed to the existence of an oxygen vacancy, enabling a reduction in the energy barrier and a broadening of the energy distribution. Interestingly, La-doping could ultimately improve the capacity and is thus worth further exploration, particularly for the design of advanced cathodic materials.

While aqueous Zn-Na hybrid batteries have garnered widespread attention because of their low cost and high safety, it is still challenging to achieve long cycle-life and stable discharge-voltage due to sluggish reaction kinetics, zinc dendrite formation, and side reactions. Herein, we design a Zn2+/Na+ dual-salt battery, in which sodiation of the NVP cathode favors zinc intercalation under an energy threshold, leading to decoupled redox reactions on the cathode and anode. Systematic investigations of the electrolyte effects show that the ion intercalation mechanism and the kinetics in the mixture of triflate- and acetate-based electrolytes are superior to those in the common acetate-only electrolytes. As a result, we have achieved fast discharging capability, suppressed zinc dendrites, a stable discharge voltage at 1.45 V with small polarization, and nearly 100% Columbic efficiency in the dual-salt mixture electrolyte with optimized concentration of 1 M Zn(OAc)2 + 1 M NaCF3SO3. This work demonstrates the importance of electrolyte regulation in aqueous dual-salt hybrid batteries for the energy storage.

Electromagnetic (EM) wave technology has greatly promoted the development of information industry and facilitated human life. At the same time, EM pollution caused by excessive use of EM waves will endanger human health and disrupt the normal operation of instruments. Therefore, compelling immediate action needs to be taken to solve EM pollution and interference problem. One-dimensional carbon has become a potential candidate to solve these problems because of its high dielectric loss, significant thermodynamic stability, high specific surface area, and low density. In this paper, the application of one-dimensional carbon materials and magnetic materials and dielectric materials in absorbing EM waves is introduced, and the future development direction is prospected, which provides some feasible ideas for more scientists.

Because of its high theoretical capacity, BiVO4 is expected to be employed in lithium-ion battery anodes. Herein, carbon-coated BiVO4 (BiVO4@C) nano-composite was prepared through molten salt method accompanied by high-energy planetary milling and investigated as an anode material for Li-ion batteries. X-ray diffraction, scan electron microscopy, and transmission electron microscope were used to study the crystallization and microstructure of the samples. Moreover, compared with pure BiVO4, the BiVO4@C electrode shows competitive electrochemical performance with a reversible capacity of 700 mAh g−1 over 200 cycles at 100 mA g−1. It also exhibits stable long cycle life with delithiation capacity of 531 mAh g−1 after 500 cycles at 200 mA g−1 and 340 mAh g−1 after 1200 cycles at 500 mA g−1. The molten salt method combined with ball milling can be used as a new method to synthesize BiVO4@C anode material for lithium-ion batteries.

The catalytic effect of rare-earth hydrogen storage alloy is investigated for dehydrogenation of alane, which shows a significantly reduced onset dehydrogenation temperature (86 °C) with a high-purity hydrogen storage capacity of 8.6 wt% and an improved dehydrogenation kinetics property (6.3 wt% of dehydrogenation at 100 °C within 60 min). The related mechanism is that the catalytic sites on the surface of the hydrogen storage alloy and the hydrogen storage sites of the entire bulk phase of the hydrogen storage reduce the dehydrogenation temperature of AlH3 and improve the dehydrogenation kinetic performance of AlH3. This facile and effective method significantly improves the dehydrogenation of AlH3 and provides a promising strategy for metal hydride modification.

Ion irradiation induced nucleation and growth of nanoparticles in amorphous SiC at elevated temperatures are investigated in this study. Both as-deposited amorphous and Kr ion irradiation-amorphized SiC films are used for the investigation. Similar behavior of particle precipitation in the two types of the films is observed. It is found that the threshold temperature for nucleation is between 550 and 700 K, which is considerably higher than the critical temperature for full amorphization in SiC irradiated with Kr ions. There is a temperature regime up to at least 900 K, where the nucleation and growth rates are only weakly dependent of the irradiation temperature. This temperature regime is potentially useful to tailor the size and density of nanocrystalline SiC precipitates by optimizing the ion irradiation conditions.

Biodiesel is a promising alternative fuel for diesel engines, but its high viscosity and low volatility have limitations in decreasing emissions. As a renewable alternative fuel with a high oxygen content, ethanol blended with biodiesel can decrease kinematic viscosity and improve fuel evaporation. In this study, the effects of the ethanol addition ratio on the spray, combustion, and emission performances of a diesel engine fuelled with biodiesel were investigated. The spray characteristics were measured using a high-speed camera and Malvern laser analysis, whereas the combustion and emission performances were tested on a turbocharged common rail direct injection (CRDI) diesel engine. The results show that adding ethanol to biodiesel enlarges the spray cone angle (SCA) and shortens spray tip penetration (STP). In addition, the curves of the size–volume distribution (SVD) of the atomized fuel droplets move toward a smaller diameter, and the Sauter mean diameter (SMD) of the biodiesel–ethanol (BE) blends gradually decreases with increasing ethanol proportion. At low loads, the fuel injection strategy is multi-injection, and the peak cylinder pressures (PCPs) of BE blends are 0.77–1.96% higher than that of diesel at different ethanol blending ratios. However, the peak heat release rates (PHRRs) of BE blends are 9.3–11.5% higher than that of diesel owing to a faster combustion rate, longer main-injection duration, and more hydroxyl radicals generated in the pilot-injection stage. At medium–high​ loads, the injection strategy changes to single injection, the PCPs of BE blends are roughly equivalent to that of diesel, and the PHRRs of BE blends for different ethanol blending ratios are 9.76–11.91% lower than that of diesel. This is because of the lower diffusion combustion ratio, lower heat value, and change of injection duration corresponding to the variation in fuel properties. In addition, the results of the peak pressure rise rate and the cyclic variation indicate that the higher ethanol addition ratio increases the combustion noise and decreases the combustion stability. In terms of exhaust emissions, compared with biodiesel, with increasing ethanol blending ratio, the soot emissions for different BE blends decrease by 11.28–47.23%, the NOx emissions increase by 2.68–7.04%, and the HC emissions increase by 9.99–21.47%. Considering the engine performance comprehensively, a 20% ethanol blending ratio in biodiesel is recommended.

Herein, the chelated precursor solution (Mg/BzAc) was synthesized using magnesium acetate as raw material and benzoylacetone as chemical modifier. The prepared solution was coated on (00 l)-oriented LaAlO3 (LAO) single crystal substrate to fabricate the MgO/BzAc gel films. First, ultraviolet absorption spectroscopy was employed to analyze the ultraviolet photosensitivity of the MgO/BzAc gel films and the characteristic absorption peak corresponding to π-π* transition in Mg/BzAc chelate rings was detected at the wavelength of 329 nm. It is found that the intensity of this peak decreased gradually with increase in UV irradiation time, which indicates that the MgO/BzAc gel films exhibit good ultraviolet photosensitive properties. Then, MgO crystalline films with biaxial texture were prepared by heat-treating MgO/BzAc gel films at 850 °C in air for 60 min. Finally, micro-patterned MgO films with biaxial textures were prepared on the LAO substrate using photosensitive sol-gel lithography in combination with the above heat-treatment process.

The durability of concrete material after exposure to elevated temperatures is important for the serviceability prediction of concrete structures in a fire disaster scenario. Existing researches show that an appropriate amount of basalt fiber can significantly improve the splitting tensile strength and chloride penetration resistance of concrete. However, the mechanical properties of basalt fiber concrete after elevated temperatures and its durability properties are still not clear. In this paper, the mechanical properties, carbonization law, and chloride ion penetration law of ordinary concrete and basalt fiber concrete under high temperatures are studied. The concept of a burnt layer for concrete exposed to elevated temperatures is proposed, and the thickness of this burnt layer for concrete under different temperatures was measured. The results show that the addition of basalt fiber can inhibit the carbonization of concrete at elevated temperatures, diminish the thickness of the burnt layer, and significantly improve the chloride penetration resistance of concrete.

Piezoresistive sensor based on flexible three-dimensional graphene oxide (3DGO) is regarded as one of the most significant components for the next generation of wearable electronics. Despite the promising potential, the sensitivity of 3DGO piezoresistive sensors is severely restricted by its disordered microstructure and internal elastic defects to capture tiny signals. Although considerable efforts have been dedicated to improving its performances by chemical reduction and subsequent freeze-drying processes, it is still a huge challenge to achieve a 3D GO-based sensor coupled with ultra-high sensitivity and low detection limit simultaneously. Here, a simple and cost-effective strategy is proposed to reconstruct its pristine disordered skeleton by inducing GO liquid crystals (GO LCs) with a daily-used surfactant of sodium dodecyl benzenesulfonate (SDBS), and then the flexible and ultralight 3D GO/SBDS (GS) composite aerogel with double-walled honeycomb-like architecture is successfully fabricated. The prepared 3D GS composite aerogel exhibits significantly improved sensing performances with a fine sensitivity of 1.48 kPa−1, a low detection limit of 0.05% strain, a fatigue resistance exceeding 10,000 cycles, and a fast response time of 20.86 ms. Importantly, the sensitive sensor has been applied in monitoring real-time fingertip pulse, offering a competitive alternative for the existed complex health monitoring systems.

Osteoinductivity is a crucial factor to determine the success and efficiency of posterolateral spinal fusion (PLF) by employing calcium phosphate (Ca-P) bioceramics. In this study, three kinds of Ca-P ceramics with microscale to nanoscale gain size (BCP-control, BCP-micro and BCP-nano) were prepared and their physicochemical properties were characterized. BCP-nano had the spherical shape and nanoscale gain size, BCP-micro had the spherical shape and microscale gain size, and BCP-control (BAM®) had the irregular shape and microscale gain size. The obtained BCP-nano with specific nanotopography could well regulate in vitro protein adsorption and osteogenic differentiation of MC3T3 cells. In vivo rabbit PLF procedures further confirmed that nanotopography of BCP-nano might be responsible for the stronger bone regenerative ability comparing with BCP-micro and BCP-control. Collectedly, due to nanocrystal similarity with natural bone apatite, BCP-nano has excellent efficacy in guiding bone regeneration of PLF, and holds great potentials to become an alternative to standard bone grafts for future clinical applications., Graphical abstract Image 1, Highlights • The nanocrystal of porous BCP ceramic spheres is similar to natural bone apatite. • BCP nanoceramics is conducive to protein adsorption and osteogenic differentiation of MC3T3 cells. • Osteoindutivity of BCP ceramics is a crucial factor to determine the sucess and efficiency of PLF. • BCP ceramic spheres with nanotopography hold great potential in clinical PLF applications.

Among the various anodes, Li3VO4 is a potential intercalation kind anode used in lithium-ion batteries (LIBs) that exhibits safer discharge voltage and higher capacity than graphite, a lower voltage plateau than Li4Ti5O12, and smaller volume difference in the Li+ intercalation/deintercalation process than metals and alloys. However, the comparatively low electronic conductivity, low initial coulombic efficiency (ICE) and serious capacity decay make the Li3VO4 anode unviable when it comes to practical implementation. Therefore, this paper reviews the research progress of Li3VO4 in recent years, mainly including the strategies of developing different synthesis methods to construct unique morphology, through coating, compositing or elemental doping to increase the ICE, electronic conductivity and the cycle constancy. Moreover, the application of Li3VO4 anode materials in other energy storage systems is summarized. Lastly, the development prospect and challenge of Li3VO4 anodes are discussed.

Dielectric capacitors have drawn increasing attention due to their fast charge/discharge rates and high power density. Among all known ceramic dielectric materials, antiferroelectrics are more attractive for their unique double ferroelectric hysteresis loops and higher energy densities. Here, a series of antiferroelectric ceramics x(0.95Bi0.5Na0.5TiO3-0.05SrZrO3)-(1-x)NaNbO3 (xBNTSZ-(1-x)NN, x = 0.23, 0.30, 0.35, 0.50) have been prepared. By stabilizing the antiferroelectric phase and postponing the critical electric field of the antiferroelectric-ferroelectric phase transition, an impressive discharge energy storage density of 4.08 J/cm3 at a breakdown strength of 370 kV/cm was achieved for the 0.35BNTSZ-0.65 N N. A superior comprehensive performance for the 0.50BNTSZ-0.50 N N ceramic with a discharge energy storage density (Wdis) of 3.78 J/cm3 and an efficiency of 86 % at an electric field strength of 320 kV/cm along with excellent frequency, temperature, and fatigue stabilities (fluctuations of Wdis≤±5% within 0.01∼100 Hz, Wdis≤10 % over 20∼140 °C, and Wdis≤1% over 106 cycle numbers) is realized. Furthermore, 0.50BNTSZ-0.50 N N ceramics simultaneously exhibit a high current density (622.5 A/cm2), high power density (112 MW/cm3), and fast discharge rate (t = 47 ns), all of which make it an excellent candidate for the pulsed power devices.

Titanium-based scaffolds are widely used implant materials for bone defect treatment. However, the unmatched biomechanics and poor bioactivities of conventional titanium-based implants usually lead to insufficient bone integration. To tackle these challenges, it is critical to develop novel titanium-based scaffolds that meet the bioadaptive requirements for load-bearing critical bone defects. Herein, inspired by the microstructure and mechanical properties of natural bone tissue, we developed a Ti–6Al–4V alloy (TC4)/gelatin methacrylate (GelMA) hybrid scaffold with dual bionic features (GMPT) for bone defect repair. GMPT is composed of a hard 3D-printed porous TC4 metal scaffold (PT) backbone, which mimics the microstructure and mechanical properties of natural cancellous bone, and a soft GelMA hydrogel matrix infiltrated into the pores of PT that mimics the microenvironment of the extracellular matrix. Ascribed to the unique dual bionic design, the resultant GMPT demonstrates better osteogenic and angiogenic capabilities than PT, as confirmed by the in vitro and rabbit radius bone defect experimental results. Moreover, controlling the concentration of GelMA (10%) in GMPT can further improve the osteogenesis and angiogenesis of GMPT. The fundamental mechanisms were revealed by RNA-Seq analysis, which showed that the concentration of GelMA significantly influenced the expression of osteogenesis- and angiogenesis-related genes via the Pi3K/Akt/mTOR pathway. The results of this work indicate that our dual bionic implant design represents a promising strategy for the restoration of large bone defects., Graphical abstract Image 1, Highlights • A novel TC4/GelMA hybrid scaffold (GMPT) was designed to mimic natural bone microstructure and mechanical property. • The GMPT with 10 wt% of GelMA showed best capability for promoting osteogenesis and angiogenesis. • A bioactive soft surface with suitable stiffness can activate focal adhesion pathway and the downstream PI3K/AKT pathway.

Ruthenium tablets with mean grain size of ~4‐5 μm were prepared by vacuum hot pressing (VHP), and tablets with maximum density of 12.2 g cm‐3 were obtained with sintering time of 2 h. X-ray diffraction (XRD) revealed that there was a texture change with sintering time. The microstructure of the ruthenium tablets was observed by electron backscatter diffraction (EBSD) and field emission scanning electron microscopy (FSEM). The microstructure evolution of ruthenium with sintering time is discussed.

Hydrophilic polyethylene glycol monomethyl ether (mPEG) was grafted onto Icariin (ICA) by succinic anhydride to form a polyethylene glycol-Icariin (mPEG-ICA) polymer. The structure of the polymer was characterized by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). mPEG-ICA nanoparticles loaded with ICA were prepared by physical embedding of ICA by dialysis. The particle size was determined to be (220 ± 13.7) nm, and the ζ potential was (2.30 ± 1.33) mV by dynamic light scattering (DLS). Under a transmission electron microscope (TEM), the nanoparticles were spherical, and the morphology was regular. In the medium with pH 7.4, the drug release rate of mPEG-ICA nanoparticles reached (52.80 ± 1.70)% within 72 h. At pH 6.8, the cumulative drug release of nanoparticles reached (75.66 ± 0.17)% within 48 h. Treatment of the nanoparticles with LPS-treated H9c2 cells maintained cell viability, reduced LDH release and exerted antiapoptotic effects. Moreover, ICA-loaded mPEG-ICA nanoparticles significantly decreased the mRNA expression of the myocardial inflammatory cytokines TNF-α, IL-1β and IL-6M. In conclusion, ICA-loaded mPEG-ICA nanoparticles protected against LPS-induced H9c2 cell injury.

In this work, we developed the first 3D-printed polyetheretherketone (PEEK)-based bone scaffold with multi-functions targeting challenging bone diseases such as osteosarcoma and osteomyelitis. A 3D-printed PEEK/graphene nanocomposite scaffold was deposited with a drug-laden (antibiotics and/or anti-cancer drugs) hydroxyapatite coating. The graphene nanosheets within the scaffold served as effective photothermal agents that endowed the scaffold with on-demand photothermal conversion function under near-infrared laser irradiation. The bioactive hydroxyapatite coating significantly boosted the stem cell proliferation in vitro and promoted new bone growth in vivo. The presence of antibiotics and anti-cancer drugs enabled eradication of drug-resistant bacteria and ablation of osteosarcoma cancer cells, the treatment efficacy of which can be further enhanced by on-demand laser-induced heating. The promising results demonstrate the strong potential of our multi-functional scaffold in applications such as bone defect repair and multimodal treatment of osteosarcoma and osteomyelitis.

A series of pyridinium-based chiral ionic liquid crystals were designed and synthesized. All of them exhibit enantiotropic smectic phases. The methylation on the pyridine ring not only decreases th...

This paper proposes two new radiant floor heating structures based on micro heat pipe array (MHPA), namely cement-tile floor and keel-wood floor. The numerical models for these different floor structures are established and verified by experiments. The temperature distribution and heat transfer process of each part are comprehensively obtained, and the structure is optimized. The results show that the cement-tile floor has the better heat transfer performance of the two. When under the same inlet water temperature and flow rate, the keel-wood floor’s surface temperature distribution is about 2 °C lower than that of the cement-tile floor. The inlet water temperature of cement-tile floor is about 10 °C lower than that of keel-wood structure when the floor surface temperature is the same. During a longitudinal heat transfer above MHPA, the floor surface temperature decreases by 0.5 °C for every 10 mm filling layer increase. In order to reduce the non-uniformity of the floor’s surface temperature and improve the thermal comfort of the heated room, the optimal structure for a floor is given, with the maximum surface temperature difference reduced by 3.35 °C. We used research focusing on new radiant floor heating, with advantages including high efficiency heat transfer, low water supply temperature, simple waterway structure, low resistance and leakage risk, to provide theory and data to support the application of an effective radiant floor heating based on MHPA.

Two series of acrylate liquid crystals with enantiotropic SmA and SmC phases were synthesised. With increasing the alkoxy chain length, SmC phase was favourable to be formed. The mesophases were confirmed by taking small angle X-ray scattering patterns. Moreover, a diacrylate liquid crystal with an enantiotropic SmA phase was synthesised. Smectic liquid crystal mixtures were prepared using the diacrylate liquid crystal (or a mixture of an acrylate liquid crystal and the diacrylate one) and a dichroic dye. After photopolymerisation at the SmA phase, polymeric polarisers were obtained. The degree of polarisation was increased with increasing the dye concentration and film thickness.

The exploration of future energy storage devices with lightweight, flexible, and highly efficient energy management strategy has attracted increased interest in recent years. The design and implementation of unique supercapacitor electrodes are expected to overcome these challenges. Herein, we report a facile electrochemical polymerization method to prepare sandpaper-based conductive polymer flexible supercapacitors. The prepared electrodes present hollow barnacle-like structure, and the maximum specific capacitance of the assembled supercapacitor is 303.3 mF cm−2. After 10,000 charge–discharge cycles, the capacitance retention maintains 92.7%. Moreover, the device has good flexibility, and the capacitance retention is as high as 92.5% after 2000 bending cycles, which is of great significance to applications.

Fiber-optic anemometers have attracted an increasing attention over the past decade owing to their high sensitivity, wide dynamic range, low power consumption, and immunity to electromagnetic interference. However, expensive instruments may limit their practical applications. Herein, a new type of airflow sensor based on optical micro/nanofiber (MNF) is proposed and realized. The sensing element is a flexible polydimethylsiloxane (PDMS) cantilever embedded with a U-shaped MNF. Upon exposure to airflow, the induced deflection of the cantilever results in a bending-dependent transmittance variation of the embedded MNF. The performance of the sensor can be engineered by tuning the cantilever thickness and/or the MNF diameter. When four cantilevers are arranged in two orthogonal directions, the transmittance of each cantilever will be dependent on both flow speed and direction. By analysing the output signals of the four cantilevers, omnidirectional airflow with flow speed within 15 m/s were experimentally measured. In addition, a variety of voice and respiratory signals can be monitored and distinguished in real-time using an optimized cantilever with a resolution of 0.012 m/s, presenting great potential for health monitoring applications.