Silica micro spheres are a type of inorganic filler, widely used in electronic packaging, bio-medicine, mechanical polishing, and fluid transportation due to their large specific surface area, high chemical stability, excellent temperature resistance, high mechanical strength, and environmental friendliness. This paper reviews the common preparation methods, such as sol gel method, vapor phase method and high-temperature spheroidization method, and points out the advantages and disadvantages of the methods above. In addition, their applications in composite materials are introduced, and views on the improvement of these methods and the research directions are looked into the future. In addition, this article introduces the principle, advantages, and applications of the creative and novel vapor oxidation method.

High-nickel ternary cathode materials have received extensive attention from researchers due to their advantages, including high energy density, high voltage plateau, and non-memory effect. However, limited by its deficiencies such as poor cycling stability, cations disordering, and poor thermal stability, there remains necessity for extensive and comprehensive research on high-nickel ternary cathodes. This paper focuses on the deficiencies of high nickel ternary cathode materials, and summarized recent advances in modification approaches, encompassing ions doping, surface coating, concentration gradient, co-modification, electrolyte modification and structure regulation in recent years, while also discussing and providing prospects for future research directions.

Electrocatalytic water splitting exhibits outstanding advantages for solving the critical problems of clean energy shortage and environmental pollution. Electric driven water splitting is a promising strategy for producing clean and renewable hydrogen. Metal-organic frameworks (MOFs) and their derivatives are considered as ideal porous materials for electrocatalytic H₂ production, resulting from their tailorable structure, ultra-large surface area, and design flexibility. This review starts with the reaction principle of electrocatalytic water splitting, relevant factors that determine the electrocatalytic activity, and then summarizes and exemplifies the recent progress in the development of MOFs based- and derived-electrocatalysts for water splitting. Finally, we highlighted the many challenges exist in the water splitting field, and proposed some perspectives of MOFs based- and derived-electrocatalysts for H₂ production from water splitting.

With its unique structural characteristics, hard carbon is considered to be the most promising negative electrode material to promote the industrialization of sodium-ion batteries. In addition to its layer spacing and chemical composition, the sodium storage performance of hard carbon is also closely related to nano pores. Hard carbon with ultra-micro pores, large pore volume, low specific surface area and closed pores can reduce the influence of solid electrolyte interface film on sodium storage and facilitate the embedding/removal of sodium ions. Design and regulation of hard carbon pore structure has become one of the key points to improve the performance of sodium-ion batteries. The pore structure can be effectively controlled by selecting suitable precursor materials, adjusting pyrolysis process parameters (heating rate, pyrolysis temperature), improving pretreatment methods (physical activation, chemical activation), doping heteroatoms, coating and other means. It will be the development direction of sodium-ion batteries in the future to use advanced characterization methods combined with theoretical calculation to realize reasonable design of pore structure of hard carbon materials and prepare low cost, high capacity and high cycle stability negative electrode materials.

Silver-based electrical contact material is core component to ensure low-voltage apparatus efficient and safe operation. The performance specifications directly affect the safety and reliability of electrical equipment. On account of environment protection, traditional silver cadmium oxide electrical contact material containing cadmium, a heavy metal toxic element, is being phased out of existence. With the updating and upgrading of low voltage electrical equipment, higher performance requirements are proposed for silver-based electrical contact materials. In this paper, the failure mechanism of silver based electrical contact materials and the classification of common silver based electrical contact materials are discussed. At the same time, the existing problems, composition design and process optimization of various silver based electrical contact materials are comprehensively summarized. In combination with the research and development needs of various low-voltage apparatus efficients, suggestions for the development of silver based electrical contact materials in the future are given, which provides reference for the research and development of silver based electrical contact materials.

The price of alloying element Bi is low, and it has a high solid solubility in magnesium, and with the decrease of temperature, its solid solubility decreases, and the Mg₃Bi₂ phase is precipitated, which improves the mechanical properties of magnesium. Therefore, Mg-Bi alloys have good solution and aging hardening potential. The addition of Sn, Mn, Al, Ca, Zn and other elements to Mg-Bi alloy can modulate the alloy microstructure and further increase the mechanical properties and corrosion resistance of the alloy. In this paper, the research progress of Mg-Bi alloys was introduced, and on the basis of summarizing the research achievements of Mg-Bi binary alloys, the microstructure and properties of Mg-Bi-Sn alloys, Mg-Bi-Mn alloys, Mg-Bi-Al alloys, Mg-Bi-Ca alloys, and Mg-Bi-Zn alloys were systematically summarized, and the effects of alloying on the second phase, grain size, texture and dynamic recrystallization of alloys were reviewed. The effects of alloying element types, addition amounts and hot working parameters on the mechanical properties of alloys were described, and the future research is prospected. The existing problems in the study of Mg-Bi alloys were summarized, and the future research was prospected.

All-solid-state lithium-ion battery has attracted wide attention due to its advantages of energy density and safety. As the core component of all-solid-state battery, solid-state electrolyte has a crucial impact on its performance. At present, the main solid electrolyte systems include oxides, sulfides and polymers, among which oxide solid electrolytes are relatively ideal solid electrolyte material with good performance such as energy density, stability and cycle life. However, serious interfaces contact between electrolyte and electrodes restrict the large-scale application of solid battery. Many researches focus on improving the contact of interfaces with different types of solid electrolytes. In this paper, the cutting-edge researches on the interfaces between inorganic solid electrolytes and electrodes reported in recent years are reviewed, and several main interfacial modification methods are systematically summarized. The research methods of composite positive electrode, interface processing technology optimization, interface layer introduction and composite electrolyte are introduced and their application prospects are discussed.

In this paper, the atomic structure and mechanical properties of NiNb alloys with different compositions were studied by molecular dynamics simulation. By comparing the change of glass transition temperature with the change of mixing enthalpy and mixing entropy of high temperature melt, it is found that the alloy shows a different trend before and after the component point c_Ni=0.65. At the same time, the atomic structure correlation analysis of NiNb alloy was carried out by using the methods of pair distribution function, coordination number, W-C parameter, bond pair analysis, and quasi neighbor atom, etc. It was found that some structural parameters also showed different trends before and after c_Ni=0.65, indicating that NiNb metallic glass had great differences in atomic structure before and after this component point. According to the thermodynamic and structural parameters, c_Ni=0.65 may be the dividing point of the two alloy systems. Before c_Ni=0.65, it is Nb base, while after c_Ni=0.65, it is Ni base. Finally, the mechanical properties were simulated, and it was found that the mechanical properties were mainly related to the binding mode of NiNb under different components. This study is helpful to deepen the understanding of the atomic structure and mechanical properties of metallic glass.

Cellulose is one of the most abundant resources in nature. The third-generation aerogels prepared from cellulose have both the high porosity and large specific surface area of traditional aerogels and their own advantages. However, its inherent flammability, poor mechanical properties and low thermal stability limit its application. At present, the functionalization of cellulose aerogels and the development of a variety of functionalized composite aerogels have become a research hotspot. In this paper, the preparation process, functionalization methods and main application fields of cellulose aerogels are summarized. Finally, the problems of functional cellulose aerogels are discussed.

ZnO nanocomposites with different molar ratios of Ce doping were prepared by hydrothermal method using ZnO as a photocatalyst and rare earth element Ce as an additive phase. The effect of Ce doping molar ratio on the lattice structure, microstructure and photocatalytic performance of ZnO nanocomposites was studied using methyl orange (MO) dye as the degradation object. The results showed that the Ce-ZnO nanocomposites prepared were all hexagonal wurtzite structured with an irregular granular appearance. Ce doping increased the surface roughness of ZnO. After Ce doping, no new products were produced in ZnO,      which did not affect the structure of ZnO. As the Ce doping molar ratio increased, the specific surface area of Ce ZnO gradually increased, the absorption edge first increased and then decreased, the bandgap width first decreased and then increased, and the photoluminescence intensity first decreased and then increased. The specific surface area of 0.6%Ce-ZnO reached 33.91 m²/g, with a maximum absorption edge of 394 nm and a minimum bandgap width of 2.97 eV, corresponding to the lowest photoluminescence intensity. The photocatalytic degradation test showed that with the increase of Ce doping molar ratio, the photocatalytic degradation of MO by Ce-ZnO first increased and then decreased. The degradation rate of MO by 0.6%Ce-ZnO reached its maximum value of 95.36% at 180 min. Under strong acidic or alkaline conditions, it wasn't conducive to the progress of photocatalytic reactions. Under weak acidic conditions with a pH value of 5, the degradation rate of MO by 0.6%Ce-ZnO reached a maximum of 99.16%. When the 0.6%Ce-ZnO photocatalyst was reused for 5 times, the degradation rate of MO still exceeded 70%, indicating good usage stability and economic benefits.

The composite hydrogel (PAM-LC) was prepared by one pot crosslinking polymerization with acrylamide (AM) as a monomer added into the crosslinking agent methylenebisacrylamide (MBAA) and ammonium sulfate (APS), the L-type Kara gum (LC) and potassium chloride (KCl) as the initiator. In order to expand the application of this hydrogel as an electrolyte in extreme cold conditions, the effects of lithium salt concentration and immersion time on the freezing resistance, conductivity and mechanical stability of PAM-LC based hydrogel were studied. The results show that the unsoaked hydrogel freezes at -12.68 ℃, while the hydrogel soaked in lithium chloride solution will not freeze at -75 ℃. Through electrochemical impedance spectroscopy (EIS) test, it can be concluded that the conductivity of hydrogel can reach 8.03 ms/cm at -30 ℃, and also reach 22.77 ms/cm at room temperature, with the better conductivity than common hydrogel. The mechanical property test shows that the hydrogel not soaked at room temperature has excellent mechanical properties but poor frost resistance. After immersion in 5M lithium chloride solution for 24 hours, the hydrogel (PAM LC LiCl) still shows good mechanical stability after freezing at -20 ℃.

In this paper, the rheological, electrical and mechanical properties of silver paste with different blends of epoxy resin and polyester resin were studied. The thixotropy and thixotropy recovery rate of resin silver paste were studied by rheometer, and the effect of rheology on printing film was discussed. In situ curving resistance test method was used to monitor the change of thermal curing resistance of silver resin paste. The results showed that the content of epoxy resin in silver paste had great influence on the resistance. The adhesion strength of resin silver paste on Al₂O₃ substrate was evaluated by the thrust test method, and the thermal impact performance of resin silver paste was evaluated. The results showed that when the ratio of epoxy resin to polyester resin was 1:0.6, the viscosity of C-1 silver paste was moderate, the thixotropic recovery rate was 58.03% after 10 s, and the printing surface was flat. After curing at 200 ℃ for 30 min, the resistance is about 2 Ω, the adhesion strength is about 10 N/mm², and the adhesion strength is not significantly deteriorated after thermal shock at 260 ℃. The comprehensive performance is better, and it is suitable for the process requirements of electronic components.

The g-C₃N₄/MXene@Ag (CNMA) separation membrane was constructed by vacuum-assisted self-assembly. It is shown that the introduction of Ag nanoparticles can optimize the surface wettability and transport channels of the membranes. The separation flux (for 1,2-dichloroethane/water emulsions) of the composite membrane is up to (6 812.7±106) L/(m²·h·bar) with a maximum separation efficiency of 99.7%. Notably, the CNMA separation membrane has remarkable anti-fouling performance and maintains stable separation properties after 10 consecutive uses. In addition, MXene@Ag can enhance the energy band structure, improve the photoelectric properties, provide positive spatial separation of electrons - holes (e^--h⁺) and achieve efficient removal of organic pollutants (dyes, antibiotics). The efficiency of the membrane in degrading methylene blue dye is 98%. The CNMA functional separation membrane is suitable for water environment remediation under organic pollutant scenarios. This work meets the actual wastewater treatment requirements and has a promising development.

In recent years, photocatalytic technology(PEC) has attracted much attention due to its integration of the advantages of electrochemistry and photocatalytic technology. This technology not only shows excellent catalytic performance, but also solves the problem that the traditional powder photocatalyst is difficult to separate and recycle. The substrate material of photoelectrode is the core of PEC technology, which significantly affects the efficiency of electron transfer, the recombination rate of photogenerated carrier and the stability of photoelectrode. Although PEC technology has made many achievements, the research progress of photoelectrode substrate materials has not been fully reported. In view of this, this paper aims to systematically classify the substrate materials of photoelectrode, including metals, conductive glass, carbon-based materials and other emerging materials, and review the recent research progress on these materials. The preparation method, performance and mechanism of photoelectrode are discussed in detail in order to provide readers with a comprehensive and in-depth understanding. At the same time, we also put forward some suggestions on the future research direction of optical electrode substrate materials, hoping to provide useful reference for the further development of this field.

Medical high-frequency ultrasonic transducers are widely used in fine structure imaging of human body and biological tissues. The 1-3 piezoelectric composite material has become the core material of high frequency ultrasonic transducer because of its high electromechanical coupling coefficient and low acoustic impedance. In this paper, high-performance Pb(Mg_1/3Nb_2/3)O₃-PbTiO₃ ceramic/epoxy piezoelectric composites were designed and prepared based on finite element calculation and soft template method, and the electrical properties of the materials were systematically tested. The results show that the 1-3 piezoelectric composite material has excellent acoustic comprehensive performance. The electromechanical coupling coefficient kt of the thickness expansion mode reaches 70.1%, and the acoustic impedance Za reaches 19.05 MRayl. A high-frequency ultrasonic transducer was fabricated using this material, with a-6 dB bandwidth of 85% and an insertion loss of 17.7 dB. The results show that the piezoelectric composites prepared by the soft template method have excellent comprehensive properties suitable for ultrasonic imaging, which is expected to promote the commercial application of high-frequency ultrasonic transducers.

A stable amphiphilic carbon quantum dots (CQDs) oil displacement agent (CQDs-S) was rapidly synthesized by one-step hydrothermal method with glucose as carbon source and dodecyl hydroxypropyl sulfobetaine (DHSB) as surface modifier. FTIR, TEM and DLS were used to characterize the structure, morphology and stability of CQDs-S. Interface performance test, contact angle measurement and static oil washing experiment were carried out to study the performance advantages of CQDs-S, compare with DHSB and CQDs in oil recovery, and analyze the mechanism of enhanced oil recovery. The results show that CQDs-S is a spherical particle with an average particle size of 7.8 nm, and its surface is modified with alkyl, which has amphiphilic properties and good stability. With a mass concentration of 0.1% CQDs-S, the oil-water interfacial tension is reduced to 0.96 mN/m, the contact angle is reduced to 48.5°, the static oil washing efficiency is as high as 86.8%, and the oil recovery rate in the core with a permeability of 50×10^-3 μm² is increased by 16.74%, which is significantly higher than that of CQDs and DHSB. The EOR mechanism of CQDs-S is mainly to reduce interfacial tension, change wettability and realize profile control. CQDs-S is an efficient nano oil displacement agent, which can reduce the oil-water interfacial tension, change the rock wettability, and realize profile control.

Geopolymer not only possesses the combined excellent properties of organic polymer materials, ceramic materials and cement materials, but also has many advantages such as low production energy consumption and carbon emissions, wide raw material source, and excessive consumption of solid wastes. Therefore, it has rapidly become a research hotspot in the field of inorganic cementitious material in recent years. After introducing the calcium component into geopolymer system, the interaction processes among the main gel phases may become more complicated. Moreover, microstructure and the main performance of geopolymer may be greatly affected. In this paper, we systematically review the research developments in Ca-containing geopolymer, with a particular summary and analysis on the way of introducing calcium component during geopolymer preparing process, as well as the influence rule and action mechanism of calcium component on microstructure and performance (including setting time, compressive strength, solidification/stabilization of heavy metals, resistance to chemical attack, alkali-aggregate reaction, thermal stability, and resistance to efflorescence) of geopolymer. It would provide technical reference for performance control and application study of Ca-containing geopolymer.

In this paper, ethylenediamine, diethylenetriamine and triethylene tetramine were used as N source and boric acid as B source to prepare different precursors to directly high temperature ammonolysis polymerize borocarbonitrides (BCN-x, recorded as BCN-EDA, BCN-DETA and BCN-TETA, respectively). XRD, SEM, TEM, XPS, UV-Vis, and PL were used to analyze the chemical composition, morphology, and optical properties of samples. And the photocatalytic CO₂ reduction performance of BCN-x samples was assessed without compromising agents and cocatalysts. The results show that all the prepared samples have lamellar structure, and BCN-EDA represents higher crystallinity and higher photocarrier separation efficiency. Under visible light irradiation at 350-780 nm, the produced BCN-x can reduce CO₂ to CO and CH₄, and BCN-EDA has the best photocatalytic CO₂ reduction performance, with a CO yield of 32.20 μmol/g and the photocatalytic stability can be maintained within 20 h.

In response to the problem of carbon emissions generated during the production and utilization of cement, and the decrease in mechanical properties of concrete prepared by replacing cement with solid waste materials under high dosage conditions, this article uses 4% Na₂SiO₃ to alkali excite glass powder (GP), and then replaces 50% of cement to prepare low-carbon concrete. The results indicate that the mechanical properties of low-carbon concrete are much lower than those of ordinary concrete. The addition of Na₂SiO₃ improves the mechanical properties of low-carbon concrete to a certain extent, and increases the compressive strength by 22.6%, 27.5%, 19.8%, and 17.2% at each age, respectively. The splitting tensile strength increased by 21.3%, 20.6%, 18.2%, and 16.3%. Na₂SiO₃ causes the abundant SiO₂ in the glass powder to appear obvious deconstruction phenomenon under the action of OH^-, which makes it combine with Ca, Na, K and other elements inside the low-carbon concrete to generate more C-S-H gel, C-A-S-H gel, N-A-S-H gel. At the same time, it also produces potassium A zeolite crystals with higher strength that other groups do not have, while reducing the macropore content of low-carbon concrete and optimizing the pore structure. This in turn leads to a significant improvement in the mechanical properties of low-carbon concrete. This study provides new ideas and insights for reducing carbon emissions and the use of large amounts of solid waste in concrete.

White light emitting diodes have great advantages over traditional light sources owe to their energy-saving, environmental protection, high efficiency, and so on, which have a wide range of applications in indoor lighting, outdoor lighting, automotive lamps and electronic backlighting devices. It is always the unremitting pursuit of researchers in this field to obtain warm white light emitting diodes with low correlated color temperature (CCT=2 700-4 500 K), high color rendering index (CRI, R_a>80), cost saving and suitable for human eyes. Red phosphor can effectively improve the shortcomings and enhance the luminescent performance of such devices, which plays an important role in high color rendering phosphor-converted white light emitting diodes. Therefore, its research and development is of great significance. In this paper, the research progress of Mn⁴⁺-doped fluoride red phosphor in recent years was reviewed, and the conventional and green preparation methods of this phosphor were introduced. In terms of the poor moisture stability of Mn⁴⁺-doped fluoride red phosphor, relevant studies on improving its moisture-resistance property were summarized. Prospectively, this review concludes with a brief view of potential challenges and future development directions of high-performance Mn⁴⁺ doped fluoride phosphor.

The Gibbs free energy of H⁺ adsorption on transition metal sulfide MoS₂ is close to zero, considered to be a promising cocatalyst for hydrogen production. However, the limited exposure of the active sites of MoS₂ cocatalyst limits the activity. In this work, Ni-BDC microspheres was chosen as Ni sources and templates to synthesize nickel doped MoS₂ cocatalyst via a hydrothermal method. The cocatalyst can significantly improve the photocatalytic hydrogen evolution activity of ZnIn₂S₄. The optimized photocatalyst (labelled as NMS/ZIS-10) exhibits the highest hydrogen evolution rate of 4.17 mmol/(g·h), which is 12.26 times and 2.72 times of pure ZnIn₂S₄ and MoS₂/ZnIn₂S₄ photocatalysts, respectively. In addition, NMS/ZIS-10 also exhibits significantly enhanced toxic Cr (VI) reduction activity due to the promoted charge separation. The excellent photocatalytic performance of Ni-MoS₂/ZnIn₂S₄ is mainly due to the increase of active sites caused by Ni doping, the enhancement of light absorption ability, the improvement of charge carrier separation, and the extension of electronic lifetime. The results of this study provide valuable references for optimizing the design of high-performance Mo based co catalysts.

Soft magnetic powder core generally has a low strength, which is improved by using the resin impregnation process. In this study, inactive diluent (tetrachloroethylene) and active diluent 636 (trimethylol propane triglycidyl ether) were used as the mixed diluent of the 135 epoxy resin/methyltetrahydrophthalic anhydride impregnated system, and the influence of the dosage of tetrachloroethylene on the compressive strength and the influence of impregnation process on the magnetic properties for Fe-Si-Al powder cores were studied. In addition, the formula for calculating the actual compressive strength of soft magnetic powder core was modified based on the measured compressive strength and porosity. The results show that the compressive strength of the powder core is greatly improved by the impregnation process, while the magnetic properties change slightly. When the mass ratio of resin to diluent is about 1∶2, the core compressive strength reaches a maximum value of 18.43 MPa. This indicates that the diluent can be fully and evenly mixed with the epoxy resin, and can be cross-linked and cured better with the curing agent at this ratio, which improves the mechanical properties of the epoxy resin accordingly. The research results on impregnation process and formula for calculating the compressive strength of soft magnetic powder cores in this paper can provide reference for the development of mass production processes to improve the strength of soft magnetic powder cores.

The mechanical properties of ETFE foils after aging in natural environment are the basis for long-term performance evaluation of ETFE structures. In this paper, the aging ETFE foils were selected to carry out the micro-morphology experiments and macro-mechanical tests. The standard values of mechanical parameters were analyzed based on statistical methods. The micro results show that the rough surface morphology and dense cross-section wrinkles existed and that the grain size increased by 7.8%. The breaking strength, yield stress and elastic modulus of aging ETFE foils decreased significantly. The standard values of the yield stress and elastic modulus were 11.73 MPa and 703.2 MPa, which reduced by 14.9% and 13.5%. In general, these results are critical for accurately evaluating long-term performance of ETFE structures.

With the rapid development of wearable technology in artificial intelligence, flexible sensing materials with stretchable, compressible, and twisted properties have flourished. Gallium based liquid metal (LM) has been widely used in the preparation of flexible sensing materials due to its excellent conductivity, thermal conductivity, flowability, high surface tension, and plasticity. However, there is currently a lack of comprehensive review on the methods for preparing flexible sensing materials using gallium based liquid metals, especially when combined with flexible matrix materials. This article focuses on the preparation methods of gallium based liquid metal for flexible sensing materials, including direct bonding method, droplet method, and liquid metal as initiator method. Secondly, the latest progress in the application of gallium based liquid metal flexible sensing materials is discussed. In addition, the progress made in the recyclability of gallium based liquid metal flexible sensing materials is discussed. Finally, suggestions are made on the existing problems in its current research and prospects for the future.

The functional utilization of iron ore tailings (IOT) converted into high value-added products is receiving increasing attention and expectation. Herein, mesoporous zinc silicate composites, including zincsilite composite and hemimorphite composite with flower-like morphology assembled by layered nanosheets, as well as willemite composite with ellipsoidal morphology assembled by short rods, were synthesized from iron ore tailings by introducing zinc ions via hydrothermal reaction process. Mesoporous zinc silicate composite hemimorphite has a typical narrow pore structure formed by the aggregation of sheet-like particles, with a pore width of about 3.385 nm and a specific surface area of 96.15 m²/g. The composite shows efficient adsorption capacity for the dye methylene blue(MB), with a removal rate of nearly 100% within 10 min, and has potential application prospects in the field of dye waste water treatment.

Nano-ceramic coating is a kind of ceramic coating obtained by different nano-toughening methods and preparation processes. The introduction of nano-structure can improve the brittleness of ceramic coating to a certain extent. The common toughening methods and toughening mechanism of nanostructured ceramic coatings are introduced, including whisker toughening, nanowire toughening, carbon nanotube toughening, nanoparticle toughening, nano-multilayer film toughening, nano-superlattice toughening and bionic structure toughening. The main preparation processes of nanostructured toughening ceramic coatings in recent years are briefly described. The main methods are sol-gel method, vapor deposition method, thermal spraying technology (such as plasma spraying, supersonic spraying) and magnetron sputtering. Finally, the problems and challenges in the preparation of different nano-toughened ceramic coatings are summarized, and the research direction and application prospect of nano-toughened ceramic coatings are prospected.

At present, the development of renewable energy has become an important part of the global sustainable energy strategy. Hydrogen is the cleanest energy in the world and is considered to be the most promising alternative energy. Industrial hydrogen production contains a large number of impurities. Therefore, the purification of hydrogen is an indispensable part of the use of hydrogen energy. Palladium and its alloy membranes are the most common materials for hydrogen separation, but they are too expensive and insufficient in yield. We need to find new hydrogen separation membranes with excellent performance. It is found that the hydrogen permeability coefficient of V/Nb and its alloy membranes is much larger than that of Pd, and the cost is lower than that of Pd metal, which is the best hydrogen separation membrane material to replace Pd metal. At present, there are many studies on V/Nb-based alloy membranes. This paper introduces the principle of hydrogen permeation of alloy membranes, the preparation methods of hydrogen separation membranes and their advantages and disadvantages, as well as the research status of V/Nb-based alloys in recent years, and looks forward to the future research and development trend of hydrogen separation membranes.

The research on high-performance cementitious composites has received much attention. Nanomaterials are excellent in promoting cement hydration, enhancing the densification of cement microstructure, as well as improving the mechanical properties and durability of cementitious materials, which can give the cementitious materials a variety of functionalities and reduce the amount of cement added. In this manuscript, the effects of different dimensions of inorganic nanomaterials on hydration, microstructure, mechanical properties and durability of cementitious materials are systematically sorted out from the mechanistic level of the materials, and the research direction of inorganic nanomaterials modification of cementitious materials in the future is proposed.

In this article, the surface modification methods of hollow glass microspheres and their applications in coatings were briefly introduced. The latest research progress in thermal insulation coatings, fireproof coatings, wave-absorbing coatings and anticorrosive coatings was summarized, and the future direction of the application of hollow glass microspheres in coatings was prospected.

The manganese dioxide electrode material was prepared by hydrothermal method using KMnO₄ and MnCl₂·4H₂O as raw materials. The microstructure of the material was observed by SEM and XRD, and the crystal shape was determined. The ORR electrocatalytic performance of manganese dioxide as electrode material was studied by discharge test and electrochemical test. The results show that homogeneous nanowire α-MnO₂ can be prepared when the hydrothermal reaction temperature is 180 ℃ and the molar ratio of KMnO₄:MnCl₂·4H₂O is 2.5:1. The polarization current density of the air cathode prepared by α-MnO₂ as catalyst reaches 76.15 mA/cm² at the polarization voltage of 1.0 V. It also has the smallest impedance, indicating that the resistance of oxygen reduction reaction is the least. At the current density of 10, 20, 30 and 40 mA/cm², the discharging voltage is 1.64, 1.49, 1.36 and 1.23 V, respectively, and the discharge performance is improved by about 10% compared with that of 5% platinum carbon catalyst.

As a kind of intelligent fluid with both magnetic and fluidity properties, magnetorheological fluids have been widely used in many fields. Bidisperse magnetorheological fluids, with their excellent settling stability, redispersing ability and magnetorheological properties, are one of the most promising directions for the future development of magnetorheological fluids. In light of the research progress in recent years, the stabilisation mechanism of bidisperse magnetorheological fluids is highlighted, and the magnetorheological properties of bidisperse magnetorheological fluids are reviewed based on microstructural evolution, experimental influencing factors, and intrinsic mechanics models. Finally, the industrial application of bidisperse magnetorheological fluids is proposed.

As the material basis for the survival of life, fresh water resources are facing serious challenges. Using efficient solar-driven interface evaporation (SSG) is an important means to solve the current water shortage. A new porous material conjugated microporous polymer (CMPs) plays an important role in water treatment technology. A new type of solar energy evaporator (CMC/ SCMP-PPY) was prepared by spraying polypyrrole on its surface with CMC/SCMP as a precursor. The light absorption rate was up to 91% and the photothermal conversion ability was realized. The aerogel showed good photothermal conversion performance under 1 kW/m² irradiation, and the evaporation efficiency reached 85.57%. The porous structure and hydrophilic characteristics make it have excellent water transport ability, and the stable chemical structure makes it have excellent salt resistance to prevent salt crystal deposition and clogging material channels, so that it can realize the photothermal conversion ability. This work further optimizes the purification of CMPs in wastewater, realizes the utilization of clean energy, and provides a new idea for the development of new photothermal materials.

Nanoarray of spinel transition metal oxides has unique advantages over its nanowires and nanoparticles, and has important applications in many fields such as energy storage, catalysis, magnetism and optoelectronics. In this paper, various factors (substrate, reaction temperature, reaction time, raw materials, etc.) affecting the structure and morphology of spinel transition metal oxide nanoarrays prepared by hydrothermal/solvothermal method are summarized. The correlation between the structure and morphology of nanoarrays and their properties is discussed. The related research on the hierarchical structure of spinel transition metal oxide nanoarrays is briefly introduced. It is hoped that it can promote the design and development of multifunctional or functionally integrated nanoarrays and broaden their application range.

Choosing lauric acid and glycerol as raw materials and p-toluene sulfonic acid as a catalyst, the effects of reaction temperature, reaction time, stirring speed, raw material molar ratio and catalyst dosage on the purity of glycerol monolaurate (GML) were determined through single factor test. And the inhibitory effect of GML concentration and pH value changes on Staphylococcus aureus were studied. The results showed that the highest purity of GML was obtained under the conditions of n (glycerol)∶n (lauric acid)=3∶1, reaction temperature of 180 ℃, reaction time of 3.5 h, stirring speed of 250 r/min, and p-toluenesulfonic acid dosage of 0.4 wt%. This process was the optimal synthesis process. The orthogonal experimental test showed that the synthesis temperature had the greatest impact on the purity of GML. The initial purity of GML prepared under the optimal synthesis process was 47.7%, and the purity after purification could reach 97.2%. The antibacterial performance test showed that the inhibitory effect of GML on Staphylococcus aureus was positively correlated with its concentration. When the concentration reached 12 mg/mL, the diameter of the antibacterial zone reached its maximum value of 16.1 mm. The antibacterial rates of GML against Staphylococcus aureus gradually decreased with time. Under pH values of 5.7 and 7.2, the half-lives of GML against Staphylococcus aureus were 54 and 49 hours, respectively. It can be seen that under weak acid conditions, GML has a longer antibacterial half-life and better antibacterial effect on Staphylococcus aureus.

Diamond/aluminum composites have the advantages of high thermal conductivity and low density, making them ideal cooling materials for aerospace electronic devices. However, there is a lack of comprehensive research on the factors influencing the thermal conductivity of diamond/aluminum composites, as well as their reliability. In view of the above problems, spark plasma sintering method was utilized to prepare diamond/aluminum composites with a thermal conductivity of 462 W/(m·K). It considered the effects of sintering temperature, holding time, and diamond particle size combination. Additionally, the heat spreader reliability of this diamond/aluminum composite in high and low temperature and vibration environment was studied. The results demonstrated that the diamond/aluminum composite effectively reduced the heat source temperature by 13 ℃ compared to aluminum alloy when subjected to a heat flux of 70 W/cm². Furthermore, diamond/aluminum composites can maintain stable physical properties and structural reliability in the high and low temperature and vibration environment, effectively exerting their heat dissipation capacity. Overall, diamond/aluminum composites can be presented as a reliable solution for heat dissipation in aerospace electronic devices.

PVP with different contents was added to epoxy resin/SiO₂ insulation procedures as a novel kind of reinforcing agent, and the influences of PVP on green strength, product strength and magnetic properties of FeSi magnetic powder cores were systematically investigated. The results show that PVP in green bodies contributes to the increase of the bonding force between each component of the insulating layer, as well as between the insulating layers and magnetic powders, resulting in an increase in tensile strength. Furthermore, melting PVP during the annealing process with the appropriate content would promote the rearrangement of nano silica, which significantly improves the tensile strength of the annealed products. Similarly, the formation of a stable uniform SiO₂ insulating layer at a proper dosage of PVP is also conducive to optimizing DC-bias performance, maintaining good frequency stability of permeability and low core loss. The optimal PVP dosage is determined to be 0.3 wt%, and the corresponding FeSi powder core owns a green strength of 22 N, a product strength of 305.76 N, a stable effective permeability at about 60 μ level in the frequency range of 20~2 000 kHz, a percent permeability as high as 86.5% at 8000 A/m DC-bias field and a low core loss of 522.7kW/m³ at 50 kHz/100 mT.

Postoperative bacterial infection of titanium implants is a common clinical complication. In this paper, arrays of oxygen-deficient barium titanate nanorods (BaTiO_3-x) were constructed on the Ti surface by hydrothermal and annealing treatments. The synthesis of BaTiO₃ nanorods was confirmed using scanning electron microscopy, transmission electron microscopy, and X-ray diffractometry, and the presence of oxygen vacancies was confirmed using X-ray photoelectron spectroscopy. The reactive oxygen species (ROS) generation ability of BaTiO_3-x nanorod arrays under ultrasound was verified using methyl violet (MV) as a trapping agent. The results show that BaTiO_3-x nanorod arrays can effectively generate hydroxyl radicals (·OH) under ultrasonic (US) irradiation. Antibacterial experiments were conducted with Staphylococcus aureus (S. aureus), and the antibacterial capacity of BaTiO_3-x nanorod arrays under US was investigated by the plate spread method. The results showed that the antibacterial rate of BaTiO_3-x against S. aureus reached 90.92% after 15 min of US irradiation. This study provides ideas for the preparation of antimicrobial coatings on titanium implant surfaces and lays the foundation for expanding US-responsive antimicrobial coatings.

Phase change nanocapsules (NEPCM) with n-octadecane (C₁₈) phase change material as the core material and silica (SiO₂) as the shell material were prepared by sol-gel method. A silane coupling agent, 3-Aminopropyltriethoxysilane (APTES), was added to functionalize the SiO₂ surface. In addition, the addition of APTES promoted the hydrolysis and condensation of Tetraethyl orthosilicate (TEOS) to form a dense SiO₂ shell layer. The effects of different core/shell mass ratios on the microscopic morphology and phase change enthalpy of NEPCM were investigated. Meanwhile, the properties of NEPCM, such as thermal cycling stability, leakage prevention, thermal stability, and temperature regulation of the interior of the building, were also studied in detail. The results showed that the phase change enthalpy of NEPCM changed with the change of core/shell mass ratio. At the core/shell mass ratio of 1/1.3, the phase change enthalpy of the prepared nanocapsules was the highest, reaching 140.57 J/g, with an encapsulation rate of 61.6%. Meanwhile, due to the protection of dense SiO₂ shell material, NEPCM had good leakage prevention compared with pure C₁₈. Its enthalpy only decreased by 0.13% after 150 heating-cooling cycles, which exhibited excellent thermal cycle stability and durability. In addition, when NEPCM was used in building thermal management, it effectively delayed the time for the indoor temperature to reach the peak temperature by 385 s and reduced the peak temperature by 9 ℃, which indicated that NEPCM had excellent thermal storage and thermoregulation performance. Meanwhile, the addition of APTES functionalized the NEPCM shell, and the efficient interactions between the surface amino groups and the functional groups of the organic polymer provided a broad application prospect for the efficient preparation of nanocomposites.

Graphene polystyrene composite materials were prepared by solution blending method. The effects of the mass fraction of graphene oxide (GO) in the composite materials on the phase structure, microstructure, mechanical properties, thermal properties and flame retardancy were studied through XRD, SEM, FT-IR, mechanical properties testing, thermal loss analysis, thermal conductivity and THR analysis. The results showed that polystyrene was adsorbed on the surface of GO, and the surface roughness was increased after the composite of GO and polystyrene, without changing the chain structure of the polymer after the composite. The moderate doping of GO improved the mechanical properties of graphene polystyrene composite materials. The tensile strength, fracture elongation and elastic modulus of PG-6% composite materials reached their maximum values, which were 38.8 MPa,10.37% and 1 505 MPa, respectively. Compared with pure PS, they increased by 26.38%, 8.06% and 31.90%, respectively. The thermal conductivity and thermal diffusion coefficient of composite materials first increased and then decreased with the increase of GO proportion. The thermal conductivity and thermal diffusion coefficient of PG-6% composite material reached their maximum values, which were 0.170 W/(m·K) and 0.171 mm²/s, respectively. The addition of appropriate amount of GO improved the flame retardant performance of the composite material, increasing the difficulty of ignition and reducing the heat release rate. The PG-6% composite material had the best flame retardant performance, with a maximum FPI of 0.386.

Due to the large consumption of traditional energy and environmental pollution, it is more and more important to explore efficient and clean new energy sources. Zinc-empty battery has been widely concerned as a kind of green and clean energy, but its slow cathodic oxygen reduction (ORR) reaction limits its large-scale application. Therefore, it is very important to develop an efficient and green economic non-precious metal catalyst for oxygen reduction reaction. In this paper, metal-organic framework (MOF) is used as the precursor, Fe-N doped carbon electrocatalyst (Fe-N-C) was synthesized by high temperature pyrolysis. Fe-N-C catalyst can avoid the aggregation and dissolution of metal atoms due to its strong metal-nitrogen coordination structure, so that the metal atoms are uniformly dispersed on the nitrogen-doped carbon carrier, and achieve high ORR performance. The prepared Fe-N-C-2 catalyst has abundant pore structure and a large number of Fe-N_X active sites. The half-wave potential is 0.91 V in alkaline electrolyte and 0.75 V in acidic electrolyte. At the same time, it is applied to zinc-air batteries with an open circuit voltage of up to 1.47 V and a power density of 163.1 mW/cm². This strategy provides a promising approach for designing two-dimensional structures to construct high-performance electrocatalysts.