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.

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 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.

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.

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.

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%.

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.

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, 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.

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.

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.

Cellulose nanocrystals (CNCs) is a natural polymer material with renewable and degradable properties. In this current study, based on the outstanding physical properties of graphene oxide (GO), CNCs-GO highly ordered layered structures are prepared by vacuum filtration method to improve the mechanical strength and hydrophobic properties of CNCs films. The experimental results show that when the mass fraction of graphene is 4%, the tensile strength of CNCs-GO layered film reaches a maximum of 204.4 MPa, which is 58.8% higher than that of the original CNCs film. The elastic modulus of layered films increases first and then decreases with the increase of GO mass fraction. The accuracy of mechanical test results is verified by analyzing the microstructure and dynamic thermo-mechanical properties of layered films. The contact angles of CNCs films and CNCs-GO layered films are measured, and it is found that the hydrophobic properties of the layered films are significantly improved due to the interaction between the hydrogen bond network of CNCs and the free hydroxyl groups on the GO surface.

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.

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.

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.

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%.

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.

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.

Nanocellulose is widely used as water treatment materials because of their high surface area and aspect ratio, environmental biodegradability and renewability. Chlorella grows fast and its cell wall is rich in cellulose without lignin. High quality cellulose can be obtained by simple purification. In the present work, cellulose nanofibers (CNF) were prepared from chlorella waste by homogenization, with average diameter and length of 4.1±2.3 nm and 375±35.3 nm. The physicochemical properties of the prepared CNFS were determined by various techniques, and its adsorption performance was evaluated using methylene blue trihydrate (MB) and congo red (CR) as the model dyes. Results reported in this study indicate that the adsorption of MB and CR on the CNFS follow pseudo-first-order kinetics and the pseudo-second-order. Besides, the effects of pH and dye concentrate on adsorption were also investigated. Further analysis reveals that the process of MB and CR adsorption follow the Langmuir isotherm model. The maximum capacity of cationic MB dye adsorption on the CNF is 161.25 mg/g, and anionic CR dye adsorption is 181.36 mg/g. The pH has a significant effect on the adsorption capacity of CNFS, which have maximum adsorption capacity the maximum adsorption capacity. But for CR, the lower the pH, the stronger the adsorption capacity is, in the pH range of 5 to 10.

Si nanomaterials have attracted much attention from researchers since their appearance. Their unique properties, which are different from macroscopic bulk materials, enable them to be applied in various fields. How to prepare nanomaterials with good morphology and photoelectric properties is a problem that must be solved before the application of nanomaterials. In this work, dense silicon nanowires were directly prepared on Si substrate with Ni film as catalyst, and strong luminescence in blue and purple bands was obtained. The effects of annealing temperature, N₂ flow rate for annealing atmosphere, silicon film thickness and other preparation conditions on the morphology and photoluminescence intensity of silicon nanowires were investigated. The formation and growth mechanism of silicon nanowires prepared with Ni and silicon layers were also discussed. The experimental results show that annealing temperature and N₂ flow rate play a key role in the growth of silicon nanowires, and N₂ flow rate can affect the photoluminescence intensity of silicon nanowires. Higher N₂ flow rate can promote oriented growth of silicon nanowires. Adding Si film with appropriate thickness on Ni film catalyst can also help the growth of silicon nanowires and improve the photoluminescence intensity of silicon nanowires.

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.

A carbon nanotube reinforced fly ash concrete material was prepared by using concrete with a fly ash content greater than 50% as the matrix material and multi walled carbon nanotubes (CNTs) as nanofillers, and controlling the proportion of carbon nanotubes added. The influence of different carbon nanotube content on the mechanical properties and frost resistance of high volume fly ash concrete was studied through characterization test such as FT-IR, SEM, mechanical properties and frost resistance. The results showed that the rich hydrophilic groups on the surface of carbon nanotubes promoted the hydration reaction, exerting a small-scale effect, increasing the proportion of hydration products, and making the coating of fly ash particles and aggregates more compact, resulting in the formation of a dense microstructure of carbon nanotube reinforced fly ash concrete. When the doping amount of carbon nanotubes was 0.10wt%, the compactness of concrete was the best. The addition of an appropriate amount of carbon nanotubes significantly improved the compressive strength of high content fly ash concrete at different ages, and the effect of carbon nanotubes on the strength improvement of concrete in the early hydration stage was stronger than that in the later stage. At the age of 28 d, when the doping amount of carbon nanotubes was 0.10wt%, the compressive strength of concrete reached the maximum value of 46.26 MPa. After 200 freeze-thaw cycles, the addition of carbon nanotubes significantly improved the failure morphology of concrete specimens, resulting in a decrease in the number of detachment and cracks in the specimens. When the doping amount of carbon nanotubes was 0.10wt%, the minimum mass loss rate of the concrete sample was 0.34%, and the maximum compressive strength was 25.52 MPa, indicating the best frost resistance. Comprehensive analysis showed that the optimal doping amount of carbon nanotubes was 0.10wt%.

N doped TiO₂ nanotube arrays were prepared by anodic oxidation combined with solution processing, and effects of N-doping on photoelectrochemical performances were studied. Surfaces morphologies and phase structures were characterized by X-ray diffractometer and scanning electron microscope, while the content and distribution of N in TiO₂ nanotubes were analyzed by X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and Raman spectroscopy, respectively. Chronoamperometry was used for measuring the photoelectrochemical performances under UV light and visible light respectively. Researches on the photoelectrochemical detection to organics were conducted by using TiO₂(N) NTAs as photo anode and glucose as model organics. Results show that the photocurrents of all doping samples are increased compared with pristine TiO₂ NTAs, in which the UV photocurrent of optimized TiO₂(N40) NTAs increases from 180.4 μA to 256.8 μA, the detection sensitivity increases from 0.061 μA/(μmol/L) to 0.134 μA/(μmol/L). The enhancing mechanism of the photoelectrochemical performances are studied by analyzing the optical performances, recombination rate of photogenerated carriers and electrochemical performances. Increase of optical response range and effective separation of photogenerated carriers contribute to the enhancement of N-doping TiO₂(N) NTAs' photoelectrochemical performances.

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.

With high tensile strength and elastic modulus,carbon nanofibers are widely used as toughening agent of cement concrete.By adding different contents of carbon nanofibers (0, 0.3 wt%, 0.6 wt% and 0.9 wt%) into concrete, the effects of the doping amount of carbon nanofibers on the mechanical properties and frost resistance of concrete were studied.The results show that the doping of carbon nanofibers does not produce new products, but accelerates the hydration reaction, increases the structural compactness of the modified concrete and reduces the number of pores and defects.When the doping amount of carbon nanofibers is 0.6 wt%, the morphology and structure of modified concrete are the best.With the increase of carbon nanofibers doping, the reduction ratio of compressive strength, flexural strength and wear of modified concrete first increases and then decreases, and the wear per unit area and the mass loss at 80 freeze-thaw cycles first decrease and then increase.When the doping amount of carbon nanofibers are 0.6 wt%, the compressive strength and flexural strength of modified concrete at 28 d reach the maximum, which are 47.83 and 5.92 MPa respectively. The minimum wear per unit area is 1.12%, the maximum wear reduction rate is 55.56%, and the minimum mass loss rate at 80 freeze-thaw cycles is 1.23%.According to the analysis, the optimum doping amount of carbon nanofibers is 0.6 wt%.

Silver nanowires (AgNWs) with high aspect ratio are highly desirable for its downstream applications. Increasing the concentration of AgNO₃ for synthesizing the AgNWs can improve the production efficiency, but adding the difficulty in morphology controlling of the products at the same time. Herein, elaborate morphology tuning of the AgNWs prepared in the high-concentration AgNO₃ solutions were realized. Specifically, the optimized conditions, including the types of ion additives (Fe³⁺ and Cl^-), molecular weight of polyethylene pyrrolidone (PVP) and the first-step AgNO₃ concentration as well as the addition rate of AgNO₃, were obtained by systematically exploring their effects on the size of obtained AgNWs. The optimized conditions contribute to preparation of AgNWs with diameter and length being 71.0 nm and 62.3 μm respectively, corresponding to the highest aspect ratio of 877.3. The SEM images and UV-vis spectrophotometer results show that the synergy of Fe³⁺ and Cl^- determines the generation of AgNWs with high aspect ratio. Also, the optimizations of the PVP molecular weight and the first-step concentration of AgNO₃ as well as its addition rate can further improve the aspect ratio of the AgNWs.

Cellulose was the most abundant biological molecule in nature, as a major component of plant cell wall. Nanocellulose isolated through disintegration of cellulose fibers could be used as an adsorbent for wastewater treatment due to its excellent properties. Owing to its high cellulose content and almost without lignin in the cell walls, Chlorella was a good raw material for preparing nanocellulose. In this study, Chlorella-residual based TEMPO-oxidized cellulose nanofibers (TCNF) were prepared through TEMPO-mediated oxidation processes under gentle mixing without high-energy mechanical treatments. The average diameter of TCNF is about 2 nm, whereas its average length was about 300 nm, and the carboxyl content is 1.54 mmol/g. Moreover, methylene blue (MB) was used as a model dye to measure the adsorption capacity of TCNF. The adsorption capacity is almost saturated when TCNF contacted MB for 80 min, and the adsorption kinetics coincide with the pseudo-secondary kinetics model. The adsorption of TCNF on MB is greatly affected by the pH value, with a maximum value at pH = 8. The initial concentration of MB considerably affects its adsorption on TCNF. Below the initial concentration of 10 mg/g, adsorption of TCNF considerably increases with the increase in the initial concentration of MB. And when the concentration is higher than 10 mg/L, the adsorption tends to be saturated. Based on the sorption isotherms analysis of TCNF, the Langmuir model fits best with the experimental data. Thus, TCNF surfaces are uniform and monolayer adsorption occurred. In conclusion, the preparation of TCNF from Chlorella-residual is a simple and promising scheme for the removal of cationic dyes from industrial wastewater.

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.

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.

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.

In order to explore the effect of carbon nanotubes on the properties of polyamide 56 (PA56), multi-walls carbon nanotubes (MWNTs) was modified by oxygen-plasma, and then reacted with hexanediamine to obtain amino-functionalized carbon nanotubes (AMWNTs). Furthermore, the AMWNTs/PA56 composites were prepared by melt-blending method. The changes of surface functional groups of carbon nanotubes were characterized by FT-IR and Raman spectroscopy. SEM, XRD, DSC, TG and semiconductor parameter test systems were used to analyze the microscopic morphology, crystalline structure, thermal and electrical properties of the composites, and using a torque rheometer and a filter performance tester to determine the rheological properties and spinnability of the composites. The results show that the amino groups are successfully grafted on the surface of MWNTs, and the dispersibility of AMWNTs is better. With the increase of the mass fraction of AMWNTs, the thermal properties and crystalline structure of the composites were changed, and the electrical conductivity of the composites was improved at the same time. When the mass fraction of AMWNTs is within 1.0%, it has little effect on the rheology of the composites, and the composites has good spinnability.

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.

Induced orientation of nano Fe₃O₄ modified flake alumina particles in epoxy resin (E20) were investigated under the NdFeB permanent magnetic field and the effects of magnetic field strength, induction time, mass ratio of Fe₃O₄ to alumina and filler filling rate on the thermal conductivity of the composites were studied together with the insulation strength, thermal stability of composites and the peel strength of its copper clad laminate. The thermal conductivity of the Al₂O₃@Fe₃O₄/E20 composites can be improved with the increase of magnetic field strength. When the induction time of magnetic field is more than 60 min, the thermal conductivity of the composites is almost constant. The thermal conductivity of the composites can be improved through increasing the mass ratio of Fe₃O₄ to alumina. However, considering the insulation of the composites, the Fe₃O₄ coating amount should be controlled. Under the conditions of magnetic field intensity 120 mT, induction time 60 min, mass ratio of Fe₃O₄ to alumina 1/30 and filling rate of flaky Al₂O₃@Fe₃O₄ composite particles 70 wt%, the thermal conductivity of flaky Al₂O₃@Fe₃O₄ composites is 1.45 W/(m·K), which is 34.26% higher than that of the flaky alumina particles filled composites. The temperature corresponding to 5% mass loss of the composite is 366 ℃ and the peel strength of copper clad laminate is greater than 1.74 N/mm.

The localized surface plasmon resonance (LSPR) of metal nanomaterials has unique optoelectronic properties, and the research on improving the photovoltaic performance of thin-film solar cells based on the LSPR effect has become one of the hot research fields of widespread concern at home and abroad. In this paper,ultrathin copper nanowires of face-centered cubic structure with a diameter of about 20 nm was synthesized by a low-temperature hydrothermal reduction method using glucose as reducing agent, copper chloride dihydrate as copper source, and hexadecylamine and octadecylamine as capping agents. The crystal structure, morphology and optical properties of the synthesized products were characterized by X-ray diffraction (XRD), ultraviolet-visible absorption spectroscopy (UV-Vis) and scanning electron microscopy (SEM). In addition, copper nanowires and nanoparticles were mixed as electron transport layers to utilize their LSPR effect to improve the light harvesting efficiency and electron transport efficiency of perovskite solar cells (PSCs), and the influence of the indoor photovoltaic performance of PSCs was investigated. The research shows that, compared with the device without Cu NWs, the energy conversion efficiency (PCE) of PSCs with Cu NWs under simulated sunlight with the light intensity of 100 mW/cm² increases from 18.46% to 20.47%; The PCE under the indoor LED light source of 2 000 lux has been greatly increased from the original 27.8% to 35.2%, and the indoor photovoltaic efficiency has been improved by as much as 26.6%.

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.

In order to explore the effect of nano-SiO₂ on asphalt properties, modified asphalt mixtures with different nano-SiO₂ doping contents were prepared. The properties of nano-SiO₂ modified asphalt mixtures were characterized by rutting test, water immersion Marshall test, freeze-thaw splitting test and low temperature cracking resistance test. The results show that the modified asphalt with 5wt% doping content of nano-SiO₂ has the lowest penetration and higher softening point and viscosity. Compared with the base asphalt, the rutting depth of 5% (mass fraction) nano-SiO₂ modified asphalt mixture was reduced by 45.90% and 52.27% at 45 and 60 min, respectively, the dynamic stability was improved by 60.57%, and the residue was stable after immersion in water for 48 h. The tensile strength is up to 90.69%, the freeze-thaw splitting strength ratio is up to 91.24%, the flexural tensile strength is increased by 17.70%, the maximum flexural tensile strain is increased by 11.36%, and the bending stiffness modulus is increased by 8.86%. On the whole, the high temperature performance, water stability and low temperature crack resistance of 5wt% nano-SiO₂ modified asphalt mixture have been significantly improved, and it has good road performance and application prospects.

Boron nitride nanomaterials are usually added to polymers to adjust and improve the performance of polymer matrix composites due to their good mechanical properties, insulation properties, oxidation resistance and excellent thermal conductivity. However, the incompatibility between inorganic boron nitride nanomaterials and organic polymer materials will weaken the mechanical and thermal properties of nanocomposites, making it difficult to give full play to their superior properties. Therefore, it is urgent to study the functional modification of boron nitride nanomaterials to improve the interface compatibility, improve the material dispersion ability and adjust the surface properties of nanomaterials. The research progress of functionalized modified boron nitride nanomaterials was reviewed. The structural characteristics, physical and chemical properties of boron nitride were introduced in detail. The application of functionalized modified boron nitride in polymer matrix composites was summarized. Finally, the development trend of functionalized modified boron nitride nanomaterials was prospected.