Recently Fe₃O₄ nanoparticles have been widely used in drug delivery systems due to their excellent magnetic properties and good biocompatibility. However,the surface of Fe₃O₄ nanoparticles is prone to agglomeration if it is not modified, which will affect its application performance. In this paper, Fe₃O₄ is hydrolyzed by ethyl orthosilicate (TEOS) and coated with SiO₂ layer. Then the carbon layer is coated by hydrothermal reaction. Finally, SiO₂ is etched by NaOH to form a kind of Fe₃O₄@C core-shell nanomaterials. The structure and morphology of Fe₃O₄@C nanoparticles were characterized by FT-IR, TEM and UV-Vis absorption spectroscopy, and the interface modification and related properties of nanoparticles are studied. The results show that the magnetic properties of Fe₃O₄ are not affected by the modified Fe₃O₄@C, and the specific surface area and the loading rate of Fe₃O₄ are improved. The loading rate of Fe₃O₄ reaches 98.9%. The drug release behavior of the compound interface modified Fe₃O₄@C under different pH conditions is further studied to explore the possibility that pH value could be used as a 'switch' for controlled drug release.

Graphite carbon nitride (g-C₃N₄) has attracted much attention due to its advantages such as low preparation cost, non-toxic and harmless, and stable physicochemical properties. However, the yield and photocatalytic activity of g-C₃N₄ obtained from different precursor systems are also different. In this study, urea, dicyanamide, and melamine were used as precursors to prepare carbon nitride 2D nanosheets by thermal stripping method, respectively. The effects of different precursors and thermal exfoliation temperature on the structure and photocatalytic performance of carbon nitride were systematically investigated. The results show that g-C₃N₄ 2D nanosheets with excellent photocatalytic performance can be directly prepared with urea as the precursor without thermal exfoliation, and the degradation rate of methylene blue is the highest, which is 60%. But its yield is extremely low, about 2%-3%. Carbon nitride prepared with dicyandiamide and melamine as precursors can be subjected to thermal exfoliation treatment to obtain 2D g-C₃N₄ nanosheets with a loose structure and excellent photocatalytic performance. The yields can be as high as 32.5% and 36.8%, respectively. Among them, the 2D nanosheets g-C₃N₄ prepared with dicyandiamide as a precursor treated at 580 ℃ for 4 hours exhibited the best photocatalytic activity, and its degradation efficiency of methylene blue can reach 91.1%, which is 40% higher than that of the unexfoliated sample. After 4 cycles of use, the degradation rate can still be maintained at 90%, showing good stability and repeatability.

Nanofibers have become a research hotspot by virtue of its excellent porosity and surface-to-volume ratio, and been successfully applied in the fields of capacitors, filtration and separation, wound dressings, sensors, etc. In recent years, a variety of nanofiber preparation methods have been proposed, such as electrospinning, melt-blown, centrifugal spinning and solution blow spinning, among which the solution blow spinning has the advantages of low cost, in-situ operation and high fiber production rate. This preparation process blows nanofibers by evaporating the solvent of polymer solution through high speed airflow. This paper reviews the preparation principle and technology of solution blow spinning nanofibers, focusing on the morphological effects of polymer solution, nozzle, airflow field and other process factors on solution blow spinning nanofibers, analyzes various applications of current solution jet spinning, and provides an outlook on its future development.

Using nano-TiO₂ as filler, by adjusting the doping ratio of nano-TiO₂ (0, 2 wt%, 4 wt% and 6 wt%), nano-TiO₂ modified cement-based concrete composites with different content were prepared. The mechanical properties, micro morphology and durability of concrete composites were analyzed. The results showed that with the increase of nano-TiO₂ doping content, the compressive strength and flexural strength of concrete composites first increased and then decreased, and the porosity and wear amount first decreased and then slightly increased. When the doping content of nano-TiO₂ was 4 wt%, the compressive strength and flexural strength reached the maximum at 28 d, which were 42.57 and 5.62 MPa respectively, the minimum porosity was 9.57%, the minimum wear amount was 1.81 kg/m², and the maximum wear reduction rate was 42.54%. The test of salt freezing resistance showed that after 7 freeze-thaw cycles, with the increase of nano-TiO₂ doping content, the mass loss rate continues to decreasing and the salt freezing resistance was significantly improved. SEM analysis showed that the morphology of ettringite changed from needle like to oblate shape after adding appropriate amount of nano TiO₂, which promoted the formation of gelatin and enhanced the compactness of the whole structure, thus improving the mechanical properties of the concrete composite. Comprehensive analysis shows that the optimal doping ratio of nano-TiO₂ was 4 wt%.

Manganese oxides have attracted much attention due to their excellent structural diversity and novel physical and chemical properties. The common manganese oxides MnO₂, Mn₂O₃, Mn₃O₄ and MnO have broad application prospects in catalysis, magnetic applications, energy storage, and other fields. The reduction of material dimension might lead to the improvement of performance. Therefore, a lot of efforts have been made in the preparation of manganese oxide nanowires, especially in the hydrothermal synthesis of manganese oxide nanowires with different crystal structures. In this paper, the effects of growth parameters (reaction temperature, reaction time, pH value, etc.) on the structure and morphology of manganese oxide nanowires prepared in the hydrothermal preparation process were summarized, in order to provide a reference for the hydrothermal growth of manganese oxide nanowires with controllable size and good performance.

A series ofnano CaCO₃ concrete composites are prepared by adding different contents of nano CaCO₃ (0, 2 wt%, 4 wt% and 6 wt%) into ordinary Portland cement. The lattice structure, micro morphology, pore distribution, mechanical properties and carbonation resistance of concrete composites are analyzed and characterized, and the mechanism of nano CaCO₃ toughened concrete composites is discussed. The results show that an appropriate amount of nano CaCO₃ doping makes the hydration products of concrete composites have better crystal form, higher crystallinity, denser and more uniform surface, effectively reducing the proportion of harmful holes and multi harmful holes, and improving the proportion of harmless holes and less harmful holes. When the doping content of nano CaCO₃ is 4 wt%, the surface improvement effect of concrete composites is the best, the lowest carbonation depth is 5.91 mm, and the compressive strength and splitting strength reach the maximum, which are 37.92 and 2.37 MPa respectively. It can be seen that the optimum doping ratio of nano CaCO₃ is 4 wt%.

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.

Nano-graphite modified paraffin phase change microcapsules (NGPCM) are prepared by solvent evaporation method with paraffin as core material, polysulfone as shell material and nano-graphite as modifier. The PCMs are characterized by SEM, FT-IR, DSC, and TGA to study the effects of different doses of nanographite on the chemical structure, phase change characteristics, surface morphology, thermal stability, and encapsulation rate of PCMs. The results show that when the addition amount of nano-graphite is 1.5%, the overall performance of the microcapsules is the best. The average particle size of the microcapsules is 326.6 μm, the melting temperature and melting enthalpy are 29.87 ℃ and 94.00 J/g, the crystallization temperature and crystallization enthalpy are 23.61 ℃ and 92.95 J/g, and the encapsulation rate of the microcapsules is 61.46%, showing good thermal stability.

Graphene oxide is prepared by improved Hummers method, and reduced by ascorbic acid to prepare rGO with hydrophobic properties. PLA/rGO nanofiber membrane is prepared by electrospinning, and the effect of the amount of rGO on the hydrophobicity of PLA nanofiber membrane is investigated. The infrared and Raman spectra of PLA/rGO nanofiber films show that PLA and rGO are physically mixed, and there is no chemical change in the process of electrospinning. It is found that the contact angle of nanofiber membrane increases from 118° to 139.2° when the amount of rGO is 0.14%, and the experiment shows that the membrane has good acid-base resistance. When titrating the contact angle of different pH, the contact angle of the membrane can reach more than 125°. From the oil-water separation experiment, it is found that the oil flux of PLA/rGO nanofiber membrane can reach 141.3 L/(m²·h), and the oil-water separation efficiency can reach 98.6%.

With the increasing application of nanocellulose materials, it is found that some nanocellulose composites can improve its overall performance and have low cost and wide sources. Nanocellulose materials such as subnanometer cellulose crystal (CNC), microcrystalline cellulose (MCC), nanocellulose (NFC), bacterial nanocellulose (BNC) and other materials are prepared by different methods. With the help of mechanical stretching, spinning, electric field, magnetic field and other methods, it is used to prepare directional alignment with high orientation and high performance. Nanocellulose materials with high strength and stiffness are used in textile industry, medical industry, optical devices and other fields. In this paper, these methods and materials are briefly discussed and the application characteristics of materials and methods are summarized.

With the continuous development of flexible optoelectronic technology, the traditional brittle transparent conductive film material indium tin oxide(ITO) can not meet application requirements. Silver nanowires (AgNWs) transparent conductive film have excellent electrical conductivity, light transmittance and mechanical properties, so it will be widely used in flexible optoelectronic devices. Firstly, this paper summarize the filming process of AgNWs transparent conductive films, including Meyer rod coating, spraying coating, roll-to-roll coating, vacuum filtration and printing technology, etc. Then, the optimization process of AgNWs transparent conductive film properties is discussed from photoelectric performance, stability, mechanical performance and adhesion to the substrate; Finally, the future development direction of the preparation and performance optimization of AgNWs transparent conductive films is prospected.

The polyaniline/carbon nanotubes composites are prepared by in-situ electrochemical polymerization of polyaniline (PANI) on the surface of carbon nanotubes (MWCNTs). The morphology of the prepared composites is characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). It is found that the PANI/MWCNTs composites have a fibrous structure. The electrochemical properties of the composites are investigated by cyclic voltammetry (CV) and chronopotentiometry (CP). The specific capacitance of materials is investigated by modulating pipe diameter of multi-walled carbon nanotube and thickness of polyaniline. It is found that the specific capacitance of polyaniline/carbon nanotubes composite could reach 147.6 F/g with 50 nm pipe diameter of carbon nanotubes and 5 cycles for the deposition of polyaniline when the current density is 0.5 mA/cm². These studies would provide scientific guidance and theoretical basis for the preparation of polyaniline/carbon nanotubes supercapacitor materials.

As a new strategy for the synthesis of nanomaterials, the microwave method not only has the characteristics of uniform heating and fast reaction speed, but also high sensitivity and selectivity. As a result, this review briefly introduces the microwave theory and heating mechanism, and then summarizes the single photocatalytic material, doped materials with different elements. Furthermore, the microwave fabrication strategy for constructing nanocomposites as well as the effect of microwave method on the microstructure and crystallization of the catalyst is well elucidated. We provide insights on the synthesis of high-performance semiconductor photocatalysts with high efficiency and low energy consumption. Finally, this review also puts forward the challenges facing by microwave synthesis of photocatalytic materials in practical applications and prospects for future development.

With the rapid development of electronic information technology and nanotechnology, high thermal conductivity polymer composite materials have attracted widespread attention from scholars at home and abroad. Boron Nitride Nanotubes (BNNTs) have the characteristics of stable chemical properties, excellent electrical insulation, thermal stability, high thermal conductivity, and good mechanical strength. They are combined with polymers to prepare high thermal conductivity polymer composites. It is widely used in the fields of electronic devices, aerospace, chemical engineering, microelectronic packaging, biomedical materials and solar energy utilization. This article reviews the properties, preparation methods and thermal conductivity of BNNTs.

The utilization of magnetic nanofluids as the base carrier fluid of magnetorheological fluids represents an effective approach to enhance the magnetorheological effect. However, achieving highly stable nano-composite magnetorheological fluids remains a significant challenge, encompassing both the synthesis of magnetic nanofluids and the prevention of composite particle agglomeration. In this study, Fe₃O₄ silicone oil-based magnetic nanofluids were prepared using silane coupling agent KH550 as a dispersant, followed by a novel process of co-coating dispersants to obtain nano-composite magnetorheological fluids. The surface morphology, physical phase composition and magnetic properties were characterized and analyzed using XRD, FI-IR, TEM, FE-SEM and VSM. The sedimentation stability and redispersibility of the novel nano-composite magnetorheological fluids were investigated. The results show that surface modification of micron-sized particles significantly enhances the stability and redispersibility of the nano-composite magnetorheological fluids, with optimal sedimentation stability and redispersibility observed at nanoparticle volume fraction of 8%. Furthermore, the novel nano-composite magnetorheological fluids demonstrate superior temperature resistance, remaining stable within the temperature range form -40 ℃ to 120 ℃over extended durations. Rheological properties of novel nano-composite magnetorheological fluid were also investigated demonstrating higher off-state viscosity and magnetorheological effect in comparison to conventional magnetorheological fluids. Moreover, both static and dynamic yield stresses increase with nanoparticle concentration and magnetic field strength.

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.

In this paper, natural plant polyphenol-tannic acid (TA) is used as the reducing agent of graphene oxide (GO), and the green reduction and functionalization of GO are realized through the "one-step method". Subsequently, the TA reduced graphene oxide (RGO) and single-walled carbon nanotubes (SWCNT) are combined to jointly construct a RGO/SWCNT conductive film with a three-dimensional structure. The transparent conductive film (TCF) has good electrical conductivity (when the light transmittance is 75.1%, the surface resistance is 36.1 Ω/sq), low roughness (the roughness of the film is only 5.45 nm), excellent flexibility (after 1 000 cycles of bending, the sheet resistance of the film remains unchanged) and good interfacial adhesion (the adhesion factor of the film is all > 0.9). The composite film has good performance and can be applied in the field of flexible wearable devices.

Rare earth nanomaterials exhibit excellent catalytic performance in chemical reactions due to their unique electronic layer structure and physical and chemical properties. Among them, low dimensional nanomaterials possess more excellent performance caused by their larger specific surface area and active site nunbers. Ai ming to the preparation technology and morphology control of low dimensional rare earth nanomaterials, several preparation methods such as solid-phase method, liquid-phase method, and gas-phase method were introduced in this paper. The influencing factors and control schemes of each method on the morphology of nanomaterials were discussed, and the advantages and disadvantages of each method and research progress at home and abroad were analyzed. The future development trend was pointed out. At the same time, the applications of low dimensional rare earth nanomaterials in catalytic fields such as photocatalysis, electrocatalysis, automotive exhaust treatment, and catalytic combustion was reviewed. The mechanism of rare earth catalysis and research achievements were summarized, and prospects were proposed for the current development status of rare earth nanomaterials in China.

Nano-mesoporous iron oxides have considerable application value in adsorption, separation, catalysis and other fields, with the characteristics of abundant pore structure, high specific surface area and ordered pore size distribution. Nevertheless, diverse synthesis methods can result in nano-mesoporous iron oxides with different morphologies and even different crystal phases. The product channels can be controlled to achieve a purposeful "pore making" by using different preparation methods and adjusting experimental parameters, and further applied to various fields according to its properties. In this paper, the preparation and application of nano-mesoporous iron oxide were reviewed, and the research direction in this field was put forward.

Rhodamine B is an important dye pollutant that needs to be removed. Researchers have been interested in developing and implementing various nanomaterials to degrade Rhodamine B from water. Birnessite-MnO₂ nanomaterial with a two dimensional layered structure has been widely used in degrading rhodamine B. In this paper, birnessite-MnO₂ nanoflowers were synthesized by self-decomposition reaction of potassium permanganate in 90 ℃ under acidic condition. The as-prepared samples were characterized by X-ray powder diffraction and field emission scanning electron microscopy. Sodium oleate was added to synthesize the samples with different size and the mechanism is also discussed. As the amount of sodium oleat increasing, the size of the sample obtained was smaller. The size of the as-prepared samples ranged from 50 to 800 nm. The degradation Rhodamine B property of the samples obtained was discussed. The samples synthesized were used to degrade Rhodamine B in acidic condition without light source added. The size of the sample and pH value were discussed to evaluate degradation property of the birnessite-MnO₂ nanoflower. The results show that the smaller the sample size, the better the degradation performance. When pH value was below 4, the birnessite-MnO₂ nanoflower had the best degradation property, and the degradation rate of Rhodamine B could reach 92.4%. After five cycles of degradation, the RhB degradation was above 85%.

This article briefs the basic characteristics, relative merits, and limitations of inorganic nanoscintillators that based on scintillation mechanism and associative physical phenomena. The structure features of different physical forms of nanoscintillator, as particle, film, ceramic and glass, and the applications of nanotechnology in scintillator are discussed. The critical factors affecting scintillation process under nanoscale are analyzed, and the related behaviors and mechanisms are explained from structure effect, surface effect and confined effect. The development of inorganic nanoscintillator in ionizing radiation detection is reviewed, and the application prospect is forecasted.

In this paper, Te NRs is synthesized by reducing sodium tellurite with Acinetobacter Pittii under dark aerobic conditions. The synthesized Te NRs are characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), UV-visible spectroscopy (UV-Vis) and Fourier transform infrared spectroscopy (FT-IR). The antibacterial and catalytic activities of Te NRs are also studied. The results show that the Te NRs synthesized by Acinetobacter Pittii is rod-like, with a maximum absorption peak at about 210 nm, and existed in crystal form. Te NRs treatment can produce obvious bacteriostatic zone, and the bacterial surface depression and rupture are observed under SEM. Te NRs can accelerate the degradation of Rhodamine B (RhB) by potassium peroxymonosulfate (PMS). In this study, Te NRs synthesized by Acinetobacter Pittii show significant antibacterial activity against Escherichia coli and Bacillus subtilis, suggesting that Te NRs could lead to bacterial apoptosis by destroying bacterial cell membranes. In catalytic experiments, Te NRs promote PMS to produce sulfate radical (SO^-₄·) and hydroxyl radical (HO·), which attacks C＝N and C＝O bonds and benzene ring, leading to accelerated degradation of RhB.

Carbon nanotubes (CNTs), as one-dimensional nanomaterials, have excellent electrical, thermal and mechanical properties, and are widely used as reinforcing agents for composite materials. Herein, the electrical and mechanical properties of different types of hybrid structure based on carbon nanotubes are reviewed, i.e., carbon/particles, carbon nanotube/fiber, carbon nanotube/pieces of foam layer, carbon nanotube/lightweight materials, where the underline mechanism for the enhancement of the electrical and mechanical properties are analyzed, in together with the advantages of different hybrid structures. The present review shed lights on the construction and design of carbon nanotube-based hybrid materials in the future.

Nano-photocatalysts have high efficiency, low energy consumption, no/low pollution, and are widely used in buildings dominated by cement-based materials, showing a good application prospect. The introduction of photocatalysts into cement-based materials can effectively improve their structural compactness, optimize their mechanical properties, endow them with the functions of pollutant degradation and surface self-cleaning, thus reducing the corrosion rate of cement-based materials and alleviating environmental pollution. This paper summarizes the different preparation methods of photocatalytic cement-based materials, introduces the influence of photocatalyst types on the photocatalytic properties of cement-based materials in detail, discusses the shortcomings of the current photocatalytic cement-based materials modified by nano-photocatalysts, and looks forward to them future development direction.

Using silver nanowires prepared by polyol method as conductive filler and kapok micro-fibrillated cellulose as carrier, the composite paper was prepared by vacuum filtration. The samples were characterized by scanning electron microscopy, X-ray diffractometer, X-ray photoelectron spectrometer, four-probe tester and vector network analyzer, and the effects of silver nanowire content on their electrical conductivity and electromagnetic interference shielding effectiveness were investigated. The results showed that the silver nanowires as one kind of one-dimensional silver elemental nanomaterial, were uniformly distributed in the composite paper and formed an excellent conductive network. When 2.5wt% of silver nanowires were added to the pure cellulose paper, the electrical resistance of the paper dropped from 470.57 MΩ·cm to 1.26 mΩ·cm. When the concentration of silver nanowires was increased from 2.5wt% to 10wt%, the conductivity of the paper increased from 793.65 S/cm to 3039.51 S/cm, and the electromagnetic interference shielding effectiveness increased from 38.1 dB to 61.5 dB.

A colorless and transparent crosslinked polymer film with high elastic state is quickly prepared by polyethylene glycol 2000 diacrylate (PEGDA-2000) and N-vinyl-2-pyrrolidone (NVP) onto POSS-SH via click reaction using UV initiator. The polymer film has certain absorbability for some solvents, and its absorbability rate are calculated. Its thermal stability T_d5% reaches 300 ℃. The polymer is a hydrophobic and oil-philic film with better stability and durability in neutral and acidic environments. The critical point of oil flux of the hydrophobic and oil-philic composite press cloth appears at 17 s, at which the average oil flux before the critical point of oil-water mixture is 15 651 L/(m²·h), and the separation efficiency reaches 96%.

Composite hydrogel particles are prepared by reverse suspension polymerization. Cellulose acrylic acid nanofiber (ACL-CNF) is used as the polymerization axis. Composite hydrogel microspheres P(AAACC) are prepared by reverse suspension polymerization of acrylamide (AM) and 2-acrylamide-2-methylpropanesulfonic acid (AMPS) with ammonium persulfate (NH₄)₂S₂O₈ as initiator. The polymerization process, microstructure, swelling, mechanical strength, temperature and salt resistance of P(AAACC) are studied. The results show that the equilibrium swelling ratio is 13.59 g/g at salt concentration of 10 wt% and 30.15 g/g at 120 ℃, which are 2.63 times and 3.15 times higher than that of ordinary hydrogels, respectively. When the compression ratio of composite hydrogel particles is 85%, the recovery of composite hydrogel particles is 84.8%, while the common hydrogel has been broken. TG-DTG analysis shows that the copolymerization reaction between ACL-CNF and monomer occurs, and the thermal stability is improved. After 7 days of aging under high temperature and high salt, the water retention rate of composite hydrogel particles is 92.1%, which is 11% higher than that of ordinary hydrogel, and the mechanical strength is 2.5 times higher in deionized water and 2.79 times higher in salt water.

Hydrogen production from electrolytic water is a promising green technology, and the use of low-cost carbon materials loaded with noble metals as catalyst substrates is an effective means to reduce the noble metal loading and optimize the performance of hydrogen precipitation catalysts. Herein, Pt/N-Mo₂C NFs were prepared by using ligand polymerization method to obtain precursor microspheres with high specific surface area formed by the self-assembly of nanosheets through pH regulation, and then Pt nanoparticles were uniformly loaded on the surface of nitrogen-doped molybdenum carbide by ion exchange and high temperature roasting. Due to the high dispersion of Pt nanoparticles on N-Mo₂C with multilayered structure and the synergistic effect between Pt and N-Mo₂C substrates, it exhibits very good hydrogen evolution reaction performance. The Pt/N-Mo₂C NFs possess low overpotentials (44 mV/η₁₀ and 137 mV/η₁₀₀), and Tafel slope of 46.2 mV/dec, as well as good stability. The results of this paper have implications for the design of low loading noble metal catalysts.

Water-soluble photocrosslinked poly(vinyl alcohol), N-methyl-4(4'-formylstyryl) pyridinium methosulfate acetal (SbQ-PVA) solution was coated onto silver nanowire (AgNW) films to form SbQ-PVA/AgNW composite films by a simple solution process. The optical-electrical properties and morphology of AgNW films with different surface densities before and after coating with SbQ-PVA were analyzed, and the mechanical as well as environmental stability of the AgNW films were compared with that of the SbQ-PVA/AgNW composite films. The results show that the SbQ-PVA coating does not affect the electrical conductivity of the silver nanowire network and also enhances the optical properties, resulting in a high transmittance of about 90% for composite films with sheet resistance as low as about 20 Ω/sq. Meanwhile, the mechanical stability of the SbQ-PVA/AgNW composite films is significantly enhanced, with the resistance value changing by only 1% in 5 000 bending cycle tests, and it can withstand the scratching of 3B pencil. The SbQ-PVA also brings excellent environmental stability to the composite films, which can maintain the resistance and morphology stability for 4 months in atmospheric environment, and it can also be well resisted to the corrosion of acid, alkali, and salt solutions. In addition, the SbQ-PVA/AgNW composite films are able to remain stable in deionized water ultrasonication, and this feature can be utilized with a photomask for one-step patterning of silver nanowire films. SbQ-PVA/AgNW composite films with high photovoltaic performance and stability offer new possibilities to realize high-quality flexible transparent electrodes in a simple, environmentally friendly and efficient way.

The design and synthesis of non-noble metal electrolytic hydropower catalysts with high activity and durability are of great significance for energy conversion and storage. In this study, iron doped molybdenum disulfide nanomaterials were prepared by a simple hydrothermal reaction of ferric nitrate, thioacetamide and sodium molybdate in anhydrous ethanol. It showed high oxygen evolution reaction (OER) activity. In 1 M KOH electrolyte, when the current density was 10 mA/cm², the overpotential was 250 mV, the Tafel slope was 219 mV/dec, and the Fe-MoS₂ could be stabilized for more than 10 h. The hydrogen evolution reaction (HER) activity was 220 mV when the current density reached 10 mA/cm² in 0.5 M H₂SO₄ electrolyte. In addition, in 1.0 M KOH electrolyte, Fe-MoS₂/C (anode) ∥Fe-MoS₂/C (cathode) two-electrode system has good catalytic activity for total hydrolysis with a low potential of 1.77 V at a current density of 10 mA/cm². Therefore, this study presents an effective technical support for the development of transition metal-doped transition metal sulfides with efficient electrolytic water performance.

The traditional NiTi alloy has been widely used in many fields due to its superelasticity, shape memory effect and excellent biocompatibility. For example, it has been prepared into orthodontic arch wire and vascular stent in the biomedical field. However, biomedical equipment needs precision and miniaturization, and the traditional NiTi alloy has been unable to keep up with the development. The nanocrystalline NiTi alloy after severe plastic deformation has better tensile, compressive strength, plasticity and fatigue properties than the traditional coarse and ultra-fine grained NiTi alloy. It is expected to expand the scope of application in the biomedical field. Nanocrystalline NiTi alloy can be used in the manufacture of new medical devices and orthopedic biomaterials. The combination of NiTiAg with Ag not only has excellent mechanical properties, but also has antibacterial effect. W-NiTi composite material is formed by combining with W nanowire/belt to improve the radiation opacity and make the positioning and deployment of instruments and implants in the human body easier. In recent years, there is also a new surface modification technology, ultrasonic nanocrystalline surface modification, which produces nanocrystalline on the surface of NiTi alloy to improve fatigue and corrosion resistance. This paper mainly introduces the application of existing NiTi alloys and the application prospect of nanocrystalline NiTi alloys in biomedical field.

Amorphous alloy ribbons with nominal compositions of Fe_80.5-xCo_xSi_3.5B_13.5Cu₁Nb_1.5(x=0, 3, 5, 7, 9) were prepared by melt spinning technique, which is used to investigate the effects of Co content and annealing temperature on the soft magnetic properties and organization of amorphous nanocrystalline alloys. The Fe_75.5Co₅Si_3.5B_13.5Cu₁Nb_1.5 quenched amorphous alloy under annealing temperature of 510 °C form an amorphous/nanocrystalline composite structure consisting of an amorphous matrix and nanograins and have excellent comprehensive soft magnetic properties, which contain the grain size D=13.5 nm, low coercivity H_c=2.5 A/m and high saturation magnetic induction intensity B_s=1.59 T. The magnetic domain structures on the surface of the ribbons at different annealing temperatures were observed by magnetic-optical kerr (MOKE) microscope. When the annealing temperature is 510 °C and the Co content x is 5, the internal stress release relative completely, which leads to the uniform nanocrystalline microstructure and straight clearly striped domains, and the change of the magnetic domains corresponded to the change of H_c.

In view of the uneven particle size distribution and poor stability in the current preparation methods of nano-silver (AgNPs), sodium citrate and absolute ethanol are utilized as reducing agents in this study, and sodium citrate and polyethylene pyrolidone (PVP) are used as protective agents to prepare nano-silver. In addition, the characteristics of the prepared nano-silver are characterized by ultraviolet absorption spectroscopy, XRD, SEM, TEM, EDS, Zeta potentiometer and other techniques. The results show that the nano-silver particles are spherical and face-centered cubic structure, and small particle size distribution range, average particle size around 49.3 nm and uniform dispersion are observed. Then, the indoor exposure culture method is used to explore the toxic effect of different concentrations of nano-silver on Achromobacter denitrificans. The results of the study show that AgNPs can inhibit the growth and nitrogen degradation of Achromobacter denitrificans, and the inhibitory effect becomes stronger as the concentration of AgNPs increases. The principle of toxicity is that small particles of nano silver can directly enter the bacterial body, causing bacterial metabolism disorders, while the nano silver attached to the cell surface will destroy the surface structure of the cell membrane, causing the surface membrane to rupture and the intracellular substance to leak.

Using C₄H₆O₄Zn·2H₂O as raw material, Ag doped ZnO nanomaterials were prepared by hydrothermal method. The effects of Ag doped molar mass on the structure and photocatalytic performance of ZnO nanomaterials were studied using XRD, SEM, FT-IR, PL spectroscopy and photocatalytic performance tests. The results showed that the Ag doped ZnO nanomaterials prepared by hydrothermal method had a hexagonal wurtzite structure and high crystallinity. Ag doping didn't change the lattice structure of ZnO nanomaterials and the appearance was irregular spherical. After appropriate amount of Ag doping, the particle morphology of ZnO nanomaterials tended to change to regular spherical, with particle sizes ranging from 260 to 480 nm. With the increase of Ag doping ratio, the photoluminescence intensity of ZnO nanomaterials decreased first and then increased. ZnO nanomaterials with Ag doping molar ratio of 3% had the lowest photoluminescence intensity. Taking Rhodamine B (RhB) as the degradation target, at 180 min, the degradation rate of RhB by Ag doped ZnO nanomaterials with a molar ratio of 3% reached a maximum of 93.05%, which was 64.22% higher than that of pure ZnO. After repeated use for 5 times, the degradation rate of RhB by ZnO nanomaterials in 180 min was 81.22%, and the retention rate was as high as 87.29%, indicating a high reusability.

High B_S nanocrystalline alloys (HBNAs) with high permeability, low high frequency iron loss and near zero magnetostriction are ideal for the preparation of high performance small electronic components. The B_S of Fe-based nanocrystalline alloys has been limited by the level of Fe content in the alloy composition. The search for a balance between the amorphous forming ability (glass forming ability, GFA) of the amorphous precursors and the electromagnetic properties of the back-end is a key challenge to drive the further development of HBNAs. This paper systematically describes the existing understanding of the thermodynamics and kinetics of nanocrystalline crystallization, the crystallization mechanisms and the improvement pathway of the amorphous forming ability of HBNAs. By systematically analyzing the current research status of the preparation of Fe-based nanocrystalline alloys and the problems that need to be solved, we aim to provide some inspiration and technical ideas for the development of the composition and design of the annealing process of high-performance nanocrystalline soft magnetic alloys in China.

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 use of green renewable cellulose nanocrystals (CNCs) with the ability to self-assemble photonic structures to construct flexible functional materials can provide rich visual information, reduce the cost and reduce the harm of non-degradable materials. However, due to the lack of effective soft energy consumption phase in the system, the photonic materials based on CNCs have shortcomings such as mechanical fragility and lack of dynamic optical response, which bring certain challenges to their functional expansion and application. Thus, according to the structural characteristics of CNCs, this paper introduces in detail the preparation methods and influencing factors of the current CNCs photonic membrane, and then summarizes the various synthesis and regulation strategies of the current CNCs photonic membrane from mechanical rigidity to mechanical flexibility and machine color responsiveness. At the same time, the promising application directions and future challenges of CNCs flexible functional photonic materials are emphasized in this paper.

Polymer/bentonite nanocomposite is a material that achieves composites at the nanoscale. It has the lamellar structure of bentonite, the controllability of polymers, and includes the characteristics of nanomaterials. It is precisely because of these advantages that the material is widely used in environmental protection, medical pharmacy, petrochemical and other fields. In this paper, the research progress of polymer/bentonite nanocomposites is reviewed. The structural characteristics, classification, preparation methods and structure-activity mechanism of the material are introduced. The material has two types of composite structures: intercalation structure and exfoliation structure. It has two common preparation methods: intercalation polymerization method and polymer intercalation method. The application status of the material in the main application fields is reviewed. The material is often used in environmental protection, biomedicine, petrochemical, optoelectronic fields. The current difficulties of the material are summarized. For example, the preparation mechanism needs to be further studied to broaden the application field of this material. The development direction of the material and application prospects are prospected. Since the polymer exists in the confined space of the bentonite sheet, the chain segment movement is restricted, and it is not easy to decompose at high temperature. The material has important reference value in improving the temperature resistance of polymers, and is of great significance to the development of high temperature treatment agents for wellbore working fluids.

Fe-based amorphous and nanocrystalline alloys have attracted extensive attention due to excellent soft magnetic properties, such as high permeability, low coercivity H_c and low core loss. With the development of power electronic industry, electrical equipment requires miniaturization and energy saving, which requires Fe-based amorphous and nanocrystalline alloys to have higher saturation magnetization B_s and lower H_c.In this paper, Fe₇₆Ga₅Ge₅B_13-xP_xCu₁(x=0,3,5,7)ribbons were fabricated using the melt spinning technique, and the effect of annealing temperature on the crystallization processes, microstructure and soft magnetic properties have been studied. It was found that, the substitution of B by P deteriorates the glass forming ability of the alloys, but enhance the thermal stability of the secondary crystallization. Besides, the addition of P refine the grain size and reduces coercivity on the one hand, leading to the optimal coercivity of 1.77 A/m in the x=7 ribbon annealed at 425 ℃. On the other hand, the migration of valence electrons from P to Fe decreases the magnetic moment of Fe in the residual amorphous phase and thus saturation magnetization. In addition, when the content of P is higher than 5 at%, the crystal face (200) of the grains near the surface position is parallel to the surface of the ribbon. But for the grains inside the ribbon, it is the crystal face (110) that runs parallel to the surface of the ribbon.

Carbon nanotubes are a new type of material with excellent properties, and their incorporation into cementitious materials can improve the microstructure and durability of the material. This paper reviews the research progress on the effect of nucleation, filling and bridging properties of carbon nanotubes on the microstructure and carbonation resistance of cementitious materials, and discusses the mechanism of the effect of the doping amount, dispersion method and length-to-diameter ratio of carbon nanotubes on the carbonation reaction of cementitious materials. The analysis shows that carbon nanotubes promote the hydration of cement by nucleation, increase the hydration product Ca(OH)₂, increase the alkalinity of the matrix and slow down the carbonisation, and optimise the pore structure of the material and the compactness of the interfacial transition zone by combining the filling and bridging effects, inhibit the formation of microcracks and prevent the infiltration of CO₂, thus optimising the microstructure of cement-based materials and enhancing their anti-carbonisation properties. Finally, the problems of the current research are analyzed and the prospects of its research are given.